HOHN

OK, but I'd suggest that grossing 43K for that long is borderline insane.

My argument for 3.54s is in the context of GCWR< 21K.

Heck, if I had to yank that kind of weight, I'd go to 4.56s or deeper!

600 Megawatts

You know what, I have heard this at least a half a dozen times one here from several different people, and now I just must say something... Towing 40,000 LBS with a freaking pickup truck???? How exactly does one legally and safely tow 40,000 Lbs with a 3/4 ton or 1 ton pickup truck ?? What states are you allowed to do this in, what registration is required such that you can willfully better than triple the nameplate information on the truck ??? How are you towing over 1/2 a semi's rating safely and legally with a pickup truck?? I am not talking about having the power to tow this much, we all know that a bombed CTD will do it just fine... I am talking about control, stability, braking, the 'tail wagging the dog' etc etc .. What the hell do you do, when you need to make an emergency maneuver ? I am sure the answer is, none of you have had to make an emergency maneuver, because if you had, you would have crashed.... You guys are going to kill someone someday... Wanna play semi driver??.... Buy a semi.


KP

cumminsdriver635

Sounds to me like he has 4:10's. Mine only turns about 1500rpm at 60mph...If its a 5 speed, then he probably does have 3:55's.

Eric

TORQUE

No question the Cummins will do it, but what are the fines if you get stopped, or reported? Probably pretty steep, and immediate tow of load and/or truck. Quite a bit too much for my liking also, just too dangerous for yourself and others on road if something breaks, or you lose control, or can't stop with that much excess weight. . Hopefully you're just talking a short tow, down some backcountry road doing 10mph(as I've seen a few farmers do with 18-20 bales of hay).

ridofpwrstroke

OK, but I'd suggest that grossing 43K for that long is borderline insane.

My argument for 3.54s is in the context of GCWR< 21K.

Heck, if I had to yank that kind of weight, I'd go to 4.56s or deeper

What I am saying is that the 3.55's did ok. Just didnt go that fast. When I pull our fifth wheel at 60mph in sixth gear, it cruises at 1450 rpms. It just lugs the motor too much, plus it smokes alot more. Will 200 rpms help me out? Yes. It makes much better gearing through the whole power band. The reason I stated the GVW of 43k was because you were stating the 5.63 1st gear ratio, plus axle ratio, plus 2.72:1 ratio of the low range of t-case. Well I have that, but it all doesnt help while towing the fifth wheel down the highway at 60 mph. Could I pull the fiver in 5th with the 315's? Sure. Am I using my gearing correctly? NO If I didnt want to lock up the front and rear, I would of put in an underdrive.

No question the Cummins will do it, but what are the fines if you get stopped, or reported? Probably pretty steep, and immediate tow of load and/or truck. Quite a bit too much for my liking also, just too dangerous for yourself and others on road if something breaks, or you lose control, or can't stop with that much excess weight. . Hopefully you're just talking a short tow, down some backcountry road doing 10mph(as I've seen a few farmers do with 18-20 bales of hay).

I stopped at the scale in BC, and received no fines. Believe me, it was stressful. According to some people, doesnt matter where you tow it, if your over your GVW, your a dangerous person.

You know what, I have heard this at least a half a dozen times one here from several different people, and now I just must say something... Towing 40,000 LBS with a freaking pickup truck???? How exactly does one legally and safely tow 40,000 Lbs with a 3/4 ton or 1 ton pickup truck ?? What states are you allowed to do this in, what registration is required such that you can willfully better than triple the nameplate information on the truck ??? How are you towing over 1/2 a semi's rating safely and legally with a pickup truck?? I am not talking about having the power to tow this much, we all know that a bombed CTD will do it just fine... I am talking about control, stability, braking, the 'tail wagging the dog' etc etc .. What the hell do you do, when you need to make an emergency maneuver ? I am sure the answer is, none of you have had to make an emergency maneuver, because if you had, you would have crashed.... You guys are going to kill someone someday... Wanna play semi driver??.... Buy a semi

600, you ever haul more than 2400 lbs in your truck bed? If you have, you exceeded your gross weight, your a danger to all on the road. What have you done to your truck. If you havent, buy a frickin dakota. I bought my truck to use it. Do I pull 36k often? No Did it just once. Is it legal. Prob not. Actually I know it isnt. What have I dont to my truck? Well, my dana 80 is rated for 12k (from the dana website) bedweight. I had 7450 on the rear axle. Didnt overdo that. I put on G rated tires that had a rating of 3750 per tire. X 2 = 7500. I wasnt overloaded. Tires on the trailer were rated for 3500 lbs per tire. x 8 = 28000. My actual weight on rear tires was 30k, so I was overloaded. The axles on the trailer were heavy duty dexter that I had to put on over the 10 k axles. Stability- air bags pumped up to 90 psi, braking- axles were rated for it, jake brake made it much easier, most hills didnt even touch the brake. The person driving the truck is what makes it safe or not. The fastest I went on the whole truck was 50 mph, and that was very seldom. Around corners and bumpy roads put my speed at MAYBE 25 mph. Going down hills, figure on 15-20 mph with the jake on. Brakes were cool because 2nd gear and jake on, brakes dont get used. If I needed it, I could have stopped fairly quickly. Plus, you dont ride someones bumper. You keep your distance, and let people pass. I also drove at night to keep the tires cool, and because less traffic on the road.
As far as the tail wagging, load your trailer properly. I am not saying all people can do this, just head space and timing. I am not saying that I wastoverloaded, just have to prep the truck to make it safer. I know you are going to come back with it doesnt matter, but the whole topic is gearing. I think 4.10's and 35" tires for towing is the perfect setup. The 3.55's were just a little low. With 285 tires, I think the 3.55's will work just fine, even for towing. I know because my wifes old 98 had them with an auto, and it pulled just fine. Let the bashing begin.

TxDiesel007

I hit 70 mph at 2000 rpms

With 3.54 gears and 285 sized tires, I used to have a ford with 4.10 gears, and it would hit 2000 rpms at 60 mph.

IMHO for drag racing the 3.54s are better, u might even want to go with a 3.08 ratio or so forth for better top end..

It is a trade off though, deeper gears, IE higher number have massive take off and seem to get you to top end speed quicker, BUT they have no top end whatsoever, it is just the inverse for higher gears, (lower numbers) lower take off, But better on top end due to lower RPMS and Higher MPH. All of which can be overcome by horsepower and torque anyways, your only limit for Top end is RPMS in my opinion, and they can be altered with different differential gears

hope it helps

Tx

TORQUE

Getting back to the main topic of gearing, I had 315's(33") on with my 3.55 gearing and rpm's were too low at normal hiway speed(starting to lug in 4th). Solution is to go faster(not the best option) to keep rpm's up, tow in 3rd, change gearing, or change tires back to stock(which is what I did).

Now it always stays in 4th even up fairly large hill with trailer on. Without towing it never was an issue powerwise, but if I wanted to go to a bigger tire like 33-35 inch again, I think 4.10's would put rpm's back to where engine should be running.

ridofpwrstroke

Hey torque, 315's are 35's, 285/75/16 and 305/70/16 are 33's. Same with my setup, bigger tires need lower gearing for towing.

TORQUE

Correction on my last post, I had LT305/70R16 (33") not LT315 as stated.

600 Megawatts

I am not going to argue with you or 'bash'. But towing 40 k with a pickup truck at even only 50 MPH is more than just slightly irresponsible. Period. Sorry, but that’s my opinion. Lets just agree to disagree. I'm just glad you don’t pull that load by me, where my wife and two kids drive. A lady that works at the power station with me, was put into a coma for two months, from some moron with an F250 powerstroke that was pulling a Eager Beaver trailer and a JD backhoe on it, around 25,000 trailer and backhoe weight. He thought he was cool cause he had the torque to pull it nicely. A two car accident in front of him caused by a running deer forced him into an a bit of an evasive move when all that energy behind him started moving his little toy truck around like a Honda.... he wound up in a paring lot and the young lady had just gotten back into her Grand Am when the toothless wonder's 'rig' flattened it. So yes, I am a little sensitized to this sort of thing. I tow my race trailer which is about 9,600 #'s and no matter what anyone says, I know its back there and when you have to make a quick move, it gets ugly...

KP

isissound

ok thanks i wasent expecting all of the info now would raising my gearing so that at 65mph i would b running around 12-15oo rpm would that save on fuel consumption on long runs or would i jest be eating up more fuel around town to make it not worth it