22.5" vs 3.42 swap vs new G56 swap
10-27-2007 | 08:27 AM
#31
Registered User
Joined: Oct 2004
Posts: 361
Likes: 3
From: Germany
Hi,
I have made the swap to 22.5 wheels and tires. I have 4.11s. I did this to reduce RPM at freeway speeds. First, I love the wheels. It makes the truck look smaller, but the change was not without some pain. I ran into wheel interference in front where the outer edge of the tire hit midway through turning the wheel to the lock on the rear of the plastic spash fender. I installed a 2" leveling kit and there is now adequate clearance but only just. The leveling kit required a 4 degree change in my toe setting. In the rear, the inner wheel made slight contact with the inner splash fender (both sides). A heat gun resolved that. The original shocks are just adequate with the increase in wheel weight, but when the front end suspension really unloads in a large bump, the 2" lift will cause the shocks to bottom out. So aftermarket shocks should also be considered. As far as performance, the truck really rolls well. The increase in tire width will cause the truck to follow ruts in the road more than the original, but that is normal with wider tires anyway. The increased roughness everybody talks about is caused by the much stiffer tires, but this can only be noticed when traversing bumps with sharp entry and exit edges. This detraction is largly offset by the ability to roll smoothly over large stones , curbs and other similar obstructions because of the larger rolling diameter. At highway speeds the truck is glass smooth, very, very nice. On the subject of fuel economy, I expected 15% improvement and I only observed 10% and it shifted the ideal, most economical truck speed upwards 10 MPH, but the new wheels also cause a loss of economy with speeds below 30 MPH. I am very satisfied with the change and hope to recoup some of the investment at least with tire longevity.
Steve
I have made the swap to 22.5 wheels and tires. I have 4.11s. I did this to reduce RPM at freeway speeds. First, I love the wheels. It makes the truck look smaller, but the change was not without some pain. I ran into wheel interference in front where the outer edge of the tire hit midway through turning the wheel to the lock on the rear of the plastic spash fender. I installed a 2" leveling kit and there is now adequate clearance but only just. The leveling kit required a 4 degree change in my toe setting. In the rear, the inner wheel made slight contact with the inner splash fender (both sides). A heat gun resolved that. The original shocks are just adequate with the increase in wheel weight, but when the front end suspension really unloads in a large bump, the 2" lift will cause the shocks to bottom out. So aftermarket shocks should also be considered. As far as performance, the truck really rolls well. The increase in tire width will cause the truck to follow ruts in the road more than the original, but that is normal with wider tires anyway. The increased roughness everybody talks about is caused by the much stiffer tires, but this can only be noticed when traversing bumps with sharp entry and exit edges. This detraction is largly offset by the ability to roll smoothly over large stones , curbs and other similar obstructions because of the larger rolling diameter. At highway speeds the truck is glass smooth, very, very nice. On the subject of fuel economy, I expected 15% improvement and I only observed 10% and it shifted the ideal, most economical truck speed upwards 10 MPH, but the new wheels also cause a loss of economy with speeds below 30 MPH. I am very satisfied with the change and hope to recoup some of the investment at least with tire longevity.
Steve
10-27-2007 | 09:31 AM
#32
Registered User
Joined: Oct 2004
Posts: 361
Likes: 3
From: Germany
Hi again,
Here are a few more notes on the change to 22.5 wheels. First the quality of this ALCOA wheel is SOOOoo much better than the other aftermarket wheels, no real comparison can be made. Yes, there is a significant increase in unspung weight, but 345 lbs, not 500. Yes, they probably will cause a shorter life of wheel bearings and ball joints, but depending on the way the vehicle is driven, it may be insignificant. Only time will tell. The longevity of the tire is due to the load rating of the tire and the associated harder compound. They are designed to support 7500 lbs per wheel and in this application, it is much less. My vehicle curb weight empty is 8001 lbs with a full tank of fuel. I am using Hankook 245/22.5 load G tires. They have a Shore A hardness of 61 at 10 degrees C. They have much more traction than the original load E tires. I suspected they would have poor traction in snow and ice, but they really work well. My wheels are 36.5" in diameter. I also expected the tires to roll under the rims a bit on fast turns. They don't. (very stiff sidewalls) The truck handles very precisely, even with the 5" increase in vehicle height in front. (3" in back) The engine now turns 1800 RPM at 70 MPH and 1st gear is much more useful. I have had the truck going 110 MPH, which is way faster than it should be driven and still pulling hard. I have no idea on the speed rating of the tires though and I have no intention of testing it either. I am seeing 18.5 mpg rural driving 17 mpg city and 16 mpg at 75 MPH. I have settled on 604 revolutions per mile with the DRB3 to adjust the speedometer for accuracy.
Steve
Here are a few more notes on the change to 22.5 wheels. First the quality of this ALCOA wheel is SOOOoo much better than the other aftermarket wheels, no real comparison can be made. Yes, there is a significant increase in unspung weight, but 345 lbs, not 500. Yes, they probably will cause a shorter life of wheel bearings and ball joints, but depending on the way the vehicle is driven, it may be insignificant. Only time will tell. The longevity of the tire is due to the load rating of the tire and the associated harder compound. They are designed to support 7500 lbs per wheel and in this application, it is much less. My vehicle curb weight empty is 8001 lbs with a full tank of fuel. I am using Hankook 245/22.5 load G tires. They have a Shore A hardness of 61 at 10 degrees C. They have much more traction than the original load E tires. I suspected they would have poor traction in snow and ice, but they really work well. My wheels are 36.5" in diameter. I also expected the tires to roll under the rims a bit on fast turns. They don't. (very stiff sidewalls) The truck handles very precisely, even with the 5" increase in vehicle height in front. (3" in back) The engine now turns 1800 RPM at 70 MPH and 1st gear is much more useful. I have had the truck going 110 MPH, which is way faster than it should be driven and still pulling hard. I have no idea on the speed rating of the tires though and I have no intention of testing it either. I am seeing 18.5 mpg rural driving 17 mpg city and 16 mpg at 75 MPH. I have settled on 604 revolutions per mile with the DRB3 to adjust the speedometer for accuracy.
Steve
10-27-2007 | 12:17 PM
#33
Registered User
Joined: Feb 2005
Posts: 917
Likes: 0
From: Omaha
You already tested it. Most 22.5-24.5 tires are speed rated to 75mph.
10-27-2007 | 04:31 PM
#34
Registered User
Joined: Jul 2006
Posts: 632
Likes: 0
From: Redding, CA
Hi,
I have made the swap to 22.5 wheels and tires. I have 4.11s. I did this to reduce RPM at freeway speeds. First, I love the wheels. It makes the truck look smaller, but the change was not without some pain. I ran into wheel interference in front where the outer edge of the tire hit midway through turning the wheel to the lock on the rear of the plastic spash fender. I installed a 2" leveling kit and there is now adequate clearance but only just. The leveling kit required a 4 degree change in my toe setting. In the rear, the inner wheel made slight contact with the inner splash fender (both sides). A heat gun resolved that. The original shocks are just adequate with the increase in wheel weight, but when the front end suspension really unloads in a large bump, the 2" lift will cause the shocks to bottom out. So aftermarket shocks should also be considered. As far as performance, the truck really rolls well. The increase in tire width will cause the truck to follow ruts in the road more than the original, but that is normal with wider tires anyway. The increased roughness everybody talks about is caused by the much stiffer tires, but this can only be noticed when traversing bumps with sharp entry and exit edges. This detraction is largly offset by the ability to roll smoothly over large stones , curbs and other similar obstructions because of the larger rolling diameter. At highway speeds the truck is glass smooth, very, very nice. On the subject of fuel economy, I expected 15% improvement and I only observed 10% and it shifted the ideal, most economical truck speed upwards 10 MPH, but the new wheels also cause a loss of economy with speeds below 30 MPH. I am very satisfied with the change and hope to recoup some of the investment at least with tire longevity.
Steve]
And....
Hi again,
Here are a few more notes on the change to 22.5 wheels. First the quality of this ALCOA wheel is SOOOoo much better than the other aftermarket wheels, no real comparison can be made. Yes, there is a significant increase in unspung weight, but 345 lbs, not 500. Yes, they probably will cause a shorter life of wheel bearings and ball joints, but depending on the way the vehicle is driven, it may be insignificant. Only time will tell. The longevity of the tire is due to the load rating of the tire and the associated harder compound. They are designed to support 7500 lbs per wheel and in this application, it is much less. My vehicle curb weight empty is 8001 lbs with a full tank of fuel. I am using Hankook 245/22.5 load G tires. They have a Shore A hardness of 61 at 10 degrees C. They have much more traction than the original load E tires. I suspected they would have poor traction in snow and ice, but they really work well. My wheels are 36.5" in diameter. I also expected the tires to roll under the rims a bit on fast turns. They don't. (very stiff sidewalls) The truck handles very precisely, even with the 5" increase in vehicle height in front. (3" in back) The engine now turns 1800 RPM at 70 MPH and 1st gear is much more useful. I have had the truck going 110 MPH, which is way faster than it should be driven and still pulling hard. I have no idea on the speed rating of the tires though and I have no intention of testing it either. I am seeing 18.5 mpg rural driving 17 mpg city and 16 mpg at 75 MPH. I have settled on 604 revolutions per mile with the DRB3 to adjust the speedometer for accuracy.
Steve
I have made the swap to 22.5 wheels and tires. I have 4.11s. I did this to reduce RPM at freeway speeds. First, I love the wheels. It makes the truck look smaller, but the change was not without some pain. I ran into wheel interference in front where the outer edge of the tire hit midway through turning the wheel to the lock on the rear of the plastic spash fender. I installed a 2" leveling kit and there is now adequate clearance but only just. The leveling kit required a 4 degree change in my toe setting. In the rear, the inner wheel made slight contact with the inner splash fender (both sides). A heat gun resolved that. The original shocks are just adequate with the increase in wheel weight, but when the front end suspension really unloads in a large bump, the 2" lift will cause the shocks to bottom out. So aftermarket shocks should also be considered. As far as performance, the truck really rolls well. The increase in tire width will cause the truck to follow ruts in the road more than the original, but that is normal with wider tires anyway. The increased roughness everybody talks about is caused by the much stiffer tires, but this can only be noticed when traversing bumps with sharp entry and exit edges. This detraction is largly offset by the ability to roll smoothly over large stones , curbs and other similar obstructions because of the larger rolling diameter. At highway speeds the truck is glass smooth, very, very nice. On the subject of fuel economy, I expected 15% improvement and I only observed 10% and it shifted the ideal, most economical truck speed upwards 10 MPH, but the new wheels also cause a loss of economy with speeds below 30 MPH. I am very satisfied with the change and hope to recoup some of the investment at least with tire longevity.
Steve]
And....
Hi again,
Here are a few more notes on the change to 22.5 wheels. First the quality of this ALCOA wheel is SOOOoo much better than the other aftermarket wheels, no real comparison can be made. Yes, there is a significant increase in unspung weight, but 345 lbs, not 500. Yes, they probably will cause a shorter life of wheel bearings and ball joints, but depending on the way the vehicle is driven, it may be insignificant. Only time will tell. The longevity of the tire is due to the load rating of the tire and the associated harder compound. They are designed to support 7500 lbs per wheel and in this application, it is much less. My vehicle curb weight empty is 8001 lbs with a full tank of fuel. I am using Hankook 245/22.5 load G tires. They have a Shore A hardness of 61 at 10 degrees C. They have much more traction than the original load E tires. I suspected they would have poor traction in snow and ice, but they really work well. My wheels are 36.5" in diameter. I also expected the tires to roll under the rims a bit on fast turns. They don't. (very stiff sidewalls) The truck handles very precisely, even with the 5" increase in vehicle height in front. (3" in back) The engine now turns 1800 RPM at 70 MPH and 1st gear is much more useful. I have had the truck going 110 MPH, which is way faster than it should be driven and still pulling hard. I have no idea on the speed rating of the tires though and I have no intention of testing it either. I am seeing 18.5 mpg rural driving 17 mpg city and 16 mpg at 75 MPH. I have settled on 604 revolutions per mile with the DRB3 to adjust the speedometer for accuracy.
Steve
These are my results almost exactly.
If you optimize tire pressure for load, the ride is very good. I run 75psi front and 23psi rear while empty. I slide this truck on dry pavement at higher speeds and a tire has yet to disbead.
Good shocks will help ride by 50% or more, especially on bumpy roads.
10-27-2007 | 08:57 PM
#35
Registered User
Joined: Apr 2003
Posts: 6,564
Likes: 6
From: Cummins Technical Center, IN
...The longevity of the tire is due to the load rating of the tire and the associated harder compound...
..They have a Shore A hardness of 61 at 10 degrees C. They have much more traction than the original load E tires. I suspected they would have poor traction in snow and ice, but they really work well...
Steve
..They have a Shore A hardness of 61 at 10 degrees C. They have much more traction than the original load E tires. I suspected they would have poor traction in snow and ice, but they really work well...
Steve
How are you seeing more traction? Can you stop faster? (I'm gonna say no) Can you corner harder? (again, I doubt it) Can you no longer spin them on a hard launch? (easily explained by unsprung weight increase)
Keep in mind that's it's very possible for the increase in unsprung weight to masquerade as better traction by reducing the power that actually gets to the wheels, thus making it tougher to smoke them at a light.
The harder compound is designed to last a long time at loads much higher than your truck is carrying. At those high loads, the tire delivers a lot more traction as well compared to the light loading of a fully-loaded Dodge Truck.
If a person STILL wants to run the big commercial rubber (which I'm convinced is the "wrong tool for the wrong job" so to speak), then 19.5s are a much better choice than the 22.5s. They are lighter, you have plenty of tire options, and you don't need to run an adapter that can precipitate bearing failure.
The adapter moves the wheel out from the hub, misaligning the load with the bearing.
I think the 22.5s aren't a great idea (as if that's unclear
), but I'm willing to concede the my concerns may be much ado about nothing....I'd sure hate to hear of someone in the ditch because his rock-hard 22.5s were skating on slick roads, though...
JMO
10-28-2007 | 02:03 AM
#36
Registered User
Joined: Jul 2007
Posts: 310
Likes: 0
From: Surgoinsville, Tennessee
Everybody has their own opinions about this setup. Why would you pay more for a set of 19.5s when you can get 22.5s with Alcoa wheels cheaper? The only thing I can say is, if you haven't tried a 22.5" setup, then you don't know anything about it. The ride is good. As far as traction, it's way better than stock and it's not because of a loss in power. You just can't compare this setup to anything else. I am very pleased with my setup and would do it again. I will say this is not the right setup if you are wanting to do some drifting, road coarse racing, or burnout contests and neither is a 19.5" setup. But for normal driving and towing, the 22.5s are a great setup. I haven't talked to one person yet that regrets doing this conversion.
10-28-2007 | 05:55 AM
#37
Registered User
Joined: Oct 2004
Posts: 361
Likes: 3
From: Germany
As a response to Hohn;
You are correct, at first glance it doesn't make sense, but I assure you it IS true. Perhaps because the footprint is much larger. The contact patch is at least 40% larger. The truck stops much quicker as well. I run 55 lbs in front and 50 lbs in the rear. This truck runs a full Banks setup and makes excellant power. With the original tires, accerating to speed on the freeway on ramps, as the engine would come up to max torque in 4th gear I would spin the rear tires and leave 4 black marks on the pavement and get sideways pretty quick. This used to occur around 40 miles an hour. The truck will only do this now when the road is wet. As far as your statement that the wheel adapter offsets the load, it simply is incorrect. In fact this was also one of my concerns, but I measured this in the front and the angle of inclination between the turning pivot and the road is still exactly in the center of the tire patch, effecting no dynamic toe loading as the steering geometry is dead neutral. In other words, the wheel offset and tire height change appears to compensate for whatever adapter offset there is. Your concerns are however well founded, but to my good fortune don't exist. The only real negative is the up front cost and the height change of the truck and I also have sidewinders in front. I know some folks like the effective 5" lift, but I don't. It adds a lot of air resistance and prevents a really large change in fuel consumption. As I stated earlier, I only see 10% improvement, but when following a big rig at 60 MPH, I can see 25 mpg plus and this can be accomplished at 2 car lengths. I am very happy with this mod. It really works well.
Steve
You are correct, at first glance it doesn't make sense, but I assure you it IS true. Perhaps because the footprint is much larger. The contact patch is at least 40% larger. The truck stops much quicker as well. I run 55 lbs in front and 50 lbs in the rear. This truck runs a full Banks setup and makes excellant power. With the original tires, accerating to speed on the freeway on ramps, as the engine would come up to max torque in 4th gear I would spin the rear tires and leave 4 black marks on the pavement and get sideways pretty quick. This used to occur around 40 miles an hour. The truck will only do this now when the road is wet. As far as your statement that the wheel adapter offsets the load, it simply is incorrect. In fact this was also one of my concerns, but I measured this in the front and the angle of inclination between the turning pivot and the road is still exactly in the center of the tire patch, effecting no dynamic toe loading as the steering geometry is dead neutral. In other words, the wheel offset and tire height change appears to compensate for whatever adapter offset there is. Your concerns are however well founded, but to my good fortune don't exist. The only real negative is the up front cost and the height change of the truck and I also have sidewinders in front. I know some folks like the effective 5" lift, but I don't. It adds a lot of air resistance and prevents a really large change in fuel consumption. As I stated earlier, I only see 10% improvement, but when following a big rig at 60 MPH, I can see 25 mpg plus and this can be accomplished at 2 car lengths. I am very happy with this mod. It really works well.
Steve
10-28-2007 | 04:09 PM
#39
Registered User
Joined: Jan 2007
Posts: 94
Likes: 0
From: Texas
I look at all 3 options. Gear swap would help with gas milesage for sure.. Gear swap here at our shop runs $375.00 per axle + the gears. Those with a 4x4 have to do both front and rear. I think it's a waste of money to do a gear swap.
The down fall to the 22.5 they weigh about 250lbs more then the factory wheels.
The 22.5 over time will save you on tires and fuel if you are not heavy with the foot. The wheels and tires have gotten a lot cheaper so if you want wheels and tires this would be the time.
The down fall to the 22.5 they weigh about 250lbs more then the factory wheels.
The 22.5 over time will save you on tires and fuel if you are not heavy with the foot. The wheels and tires have gotten a lot cheaper so if you want wheels and tires this would be the time.
10-29-2007 | 02:34 AM
#42
Registered User
Joined: Apr 2003
Posts: 6,564
Likes: 6
From: Cummins Technical Center, IN
And if the post from "performance" is alluding to me, I've never claimed to know everything about 22.5s. That, and I don't have to jump off a cliff to know it's dangerous. Reasonable people can discuss the pros and cons of certain modifications, the principles behind them, and the areas where actuality differs from theory. That's what we're doiing here.
22.5s were engineered for a specific application, and the Dodge pickup isn't it. That's not always bad-- when you can find overkill sometimes you can do well. Exhibit "A" would be the trusty engine under our hoods. The 22.5s might be that kind of overkill.
But there's no free lunch in anything having to do with physics or engineering, so you simply MUST ask yourself what you are giving up to gain the benefits of a 22.5 wheel setup. You might find in your personal cost/benfit analysis that the pros far outweigh the cons. Go for it and have fun.
I personally think the cons outweigh the pros, but I'm willing to be proven wrong. I'm disinclined to spend the kind of $$ that a 22.5 setup runs, so that skews the calculus somewhat.
jmo
10-29-2007 | 03:11 AM
#43
Registered User
Joined: Apr 2003
Posts: 6,564
Likes: 6
From: Cummins Technical Center, IN
Top Ten reasons to convert to the Big Wheels
Most 4x4s are only available with high ratio gearing, and most traffic on our nation's interstate highways moves at an average cruising speed between 70 and 80 mph.
When equipped with 16" tires, the operating efficiency is out of range at those highway speeds. For instance, in a diesel truck, the ideal operating rpm range for efficiency is usually between 1800 and 2200 rpm, and most factory truck engines will turn between 2400 and 3000 rpm at those speeds. This increases engine wear and decreases fuel economy. There is a similar situation with gasoline engines.
The overall height of a typical 16 tire on a 4x4 is about 30 inches. 245/70x19.5" tires are 33 tall and 255/70x22.5" tires are 36" tall. Using the larger tires will reduce rpm by 10 to 20 percent.
Most vehicle owners are only getting a practical 25,000 miles from their tires before seeing decreased tire performance. For premium tires, thats a $1,000 every 25,000 miles.
Most operators will get about 80,000 to 100,000 miles of wear with 19.5 tires. 22.5 tires will usually give 200,000 miles of satisfactory performance.
If you check with tire manufacturers, you will find that their tires have a four-year casing warranty. Even if you were to put 500,000 miles on these tires in four years, having had them re-capped as necessary, the warranty would still be valid.
The ride comfort using the larger tires is better than the little 16 tires because of their larger diameter and footprint.
In the average life of your truck you may buy 6 to 10 sets of tires at about $1,00000 a set. In addition, the lower rpm will reduce wear on your truck. When considering the cost of replacing your truck, these savings average about $10,00000 or more.
You save fuel because you are now operating in the ideal performance range of the vehicle. This could save you between $1,000 and $3,000. This initial investment now could save you approximately $20,000 over the life of your vehicle, provided you made the change early.
The Big Wheels and tires really look GREAT on your trucjk
Most 4x4s are only available with high ratio gearing, and most traffic on our nation's interstate highways moves at an average cruising speed between 70 and 80 mph.
When equipped with 16" tires, the operating efficiency is out of range at those highway speeds. For instance, in a diesel truck, the ideal operating rpm range for efficiency is usually between 1800 and 2200 rpm, and most factory truck engines will turn between 2400 and 3000 rpm at those speeds. This increases engine wear and decreases fuel economy. There is a similar situation with gasoline engines.
The overall height of a typical 16 tire on a 4x4 is about 30 inches. 245/70x19.5" tires are 33 tall and 255/70x22.5" tires are 36" tall. Using the larger tires will reduce rpm by 10 to 20 percent.
Most vehicle owners are only getting a practical 25,000 miles from their tires before seeing decreased tire performance. For premium tires, thats a $1,000 every 25,000 miles.
Most operators will get about 80,000 to 100,000 miles of wear with 19.5 tires. 22.5 tires will usually give 200,000 miles of satisfactory performance.
If you check with tire manufacturers, you will find that their tires have a four-year casing warranty. Even if you were to put 500,000 miles on these tires in four years, having had them re-capped as necessary, the warranty would still be valid.
The ride comfort using the larger tires is better than the little 16 tires because of their larger diameter and footprint.
In the average life of your truck you may buy 6 to 10 sets of tires at about $1,00000 a set. In addition, the lower rpm will reduce wear on your truck. When considering the cost of replacing your truck, these savings average about $10,00000 or more.
You save fuel because you are now operating in the ideal performance range of the vehicle. This could save you between $1,000 and $3,000. This initial investment now could save you approximately $20,000 over the life of your vehicle, provided you made the change early.
The Big Wheels and tires really look GREAT on your trucjk
25K for factory rubber? I say you have a tire defect or truck problem (alignment, etc). I don't know what you guys are getting with the good-for-a-year OEM tires, but the factory Michelins will typically do at least 40K-- sometimes double that. And $1K for 4 new shoes is too high, even with premium rubber. Heck, I can get premium 315s for that, never mind the stock 265 size. Needless to say, your pessimistic appraisal of the oem cost profile improperly creates that impression that the larger tires have a favorable cost profile.
Moreover, if you are getting bad mileage at 80mph, it's because your going too fast in a vehicle with bad aerodynamics
. Of course your engine is turning higher RPM-- it's not designed to run 80mph empty, it's designed to pull 65mph loaded, which it will do very nicely.If a person is spinning their engine 2400-3000 rpm in their typical usage, they made a poor choice of options or gearing or both. Maybe they're still just driving too fast. The G56 with 3.73s is about the same overall gearing as an NV5600 with 4.10s. That would put you at about 63mph at 2K rpm. At a perfectly practical interstate speed of 70mph you're at 2200 rpm. That's not that bad at all, and right in the sweet spot of engine power for towing-- as it was designed.
Ride comfort is subjective, but I'd challenge that one, too. Under certain kinds of conditions (small imperfections), the larger tires will ride better. But over very harsh pavement or big bumps, the unsprung weight of the larger 22.5s will ride very harshly. Take those 22.5s off road on some hard-packed dirt rut roads and your kidneys might be begging for replacement. Washboard would probably be really bad.
All else being equal, the factory tire wins a braking contest. The factory tire wins an accleration contest. The factory tire wins a towing-uphill accleration contest. The factory tire rides better on imperfect pavement.
I'm not sure where it got lost in translation, but TIRES ARE A WEAR ITEM. I'm not sure I see the point of 500K mile tires on a truck that most people will get rid of before it hits 100K. A hot-shotter MIGHT be a canditate for the big rubber, but they are one of the only people for whom it would be an option that would make sense. They are always on the hwy, accumulating lots of miles. They use their trucks like miniature 18-wheelers, so it makes sense that 22.5s would work well since they are doing what they are designed to do.
But unless you put on 2K miles a week in an max-load condition, the 22.5s are not the best fit for the operating profile of a light truck, especially a 4x4..
JMO
10-29-2007 | 09:32 AM
#45
Registered User
Joined: Apr 2006
Posts: 65
Likes: 0
From: Central Texas
Hi,
I have made the swap to 22.5 wheels and tires. I have 4.11s. I did this to reduce RPM at freeway speeds. First, I love the wheels. It makes the truck look smaller, but the change was not without some pain. I ran into wheel interference in front where the outer edge of the tire hit midway through turning the wheel to the lock on the rear of the plastic spash fender. I installed a 2" leveling kit and there is now adequate clearance but only just. The leveling kit required a 4 degree change in my toe setting. In the rear, the inner wheel made slight contact with the inner splash fender (both sides). A heat gun resolved that. The original shocks are just adequate with the increase in wheel weight, but when the front end suspension really unloads in a large bump, the 2" lift will cause the shocks to bottom out. So aftermarket shocks should also be considered. As far as performance, the truck really rolls well. The increase in tire width will cause the truck to follow ruts in the road more than the original, but that is normal with wider tires anyway. The increased roughness everybody talks about is caused by the much stiffer tires, but this can only be noticed when traversing bumps with sharp entry and exit edges. This detraction is largly offset by the ability to roll smoothly over large stones , curbs and other similar obstructions because of the larger rolling diameter. At highway speeds the truck is glass smooth, very, very nice. On the subject of fuel economy, I expected 15% improvement and I only observed 10% and it shifted the ideal, most economical truck speed upwards 10 MPH, but the new wheels also cause a loss of economy with speeds below 30 MPH. I am very satisfied with the change and hope to recoup some of the investment at least with tire longevity.
Steve
I have made the swap to 22.5 wheels and tires. I have 4.11s. I did this to reduce RPM at freeway speeds. First, I love the wheels. It makes the truck look smaller, but the change was not without some pain. I ran into wheel interference in front where the outer edge of the tire hit midway through turning the wheel to the lock on the rear of the plastic spash fender. I installed a 2" leveling kit and there is now adequate clearance but only just. The leveling kit required a 4 degree change in my toe setting. In the rear, the inner wheel made slight contact with the inner splash fender (both sides). A heat gun resolved that. The original shocks are just adequate with the increase in wheel weight, but when the front end suspension really unloads in a large bump, the 2" lift will cause the shocks to bottom out. So aftermarket shocks should also be considered. As far as performance, the truck really rolls well. The increase in tire width will cause the truck to follow ruts in the road more than the original, but that is normal with wider tires anyway. The increased roughness everybody talks about is caused by the much stiffer tires, but this can only be noticed when traversing bumps with sharp entry and exit edges. This detraction is largly offset by the ability to roll smoothly over large stones , curbs and other similar obstructions because of the larger rolling diameter. At highway speeds the truck is glass smooth, very, very nice. On the subject of fuel economy, I expected 15% improvement and I only observed 10% and it shifted the ideal, most economical truck speed upwards 10 MPH, but the new wheels also cause a loss of economy with speeds below 30 MPH. I am very satisfied with the change and hope to recoup some of the investment at least with tire longevity.
Steve