Inferno Ram

Hi:

I am new here. Just purchased an 06 2500 4X4 Cummins/Auto. I have ordered a Kore Recon Lift and 35" BFG MT tires slated for delivery in a week. I am a little concerned that these tires will not agree with my stock 3.73 gears. I have heard horror stories of cooked torque converters due to improper gearing. Can anyone speak from experience about the above listed combination and perhaps aleave or confirm my fears?

Sincerely,

essgeetee

Where have you heard about people killing their TC with this combo? I know LOTS on this forum (and other dodge forums) have 35" tires with 3.73's and report no problems other than a little worse mpg.

Inferno Ram

To be accurate, all of the failed TC's I have seen (all information was found on the internet) occured with a larger tire. 37, 38 & 40. I have not found any references to TC failures with 35" tires. But since I am no transmission expert, I am seeking advice. Perhaps with my lift just a few days away, my imagination is getting the best of me.

Sincerely,

no_6_oh_no

If you do a lot of stop and go driving the forward and direct clutches will start seeing excessive wear in as little as 20k. It's not as bad if you do a lot of hiway driving but city driving and towing will kill the stock tranny. Anything over a 33" tire drops the rpm's and trans pressures on shift too low and starts slippage.

swansong04

well , i have 315's on my truck an i too have 3.73's i have 55000 km on my truck and the juice with attitude for the last 30000km and i haul a camper and a car trailer with my rock crawler on the back quiet often and i have had no problem so far ..

Its All Good

If you tow a lot being that is an auto, it will feel sluggish.

Inferno Ram

I've been doing some research of my own following this post at it seems that 3.73's should work fine (at least mechanically). I'll just have to see how the 35's feel with the 3.73's and go from there.

Thanks for everyones input.

acook

I have 35's(315's so same thing) and 373's on mine and i tow 14-16K lbs of hay about every other day, i havent had a problem yet.

omaharam

There are ways to fix slugish I felt a difference going to my 315s, but I'm just gonna add another 100hp to make up for it.

omaharam

Oh yeah, I forgot. As far as mileage, I have never checked it in town, but, with the 315s and the 3.73s I got 19.7 mpg at 72mph. Before the tires, that was more like high 17s to low 18s.

essgeetee

Are you properly calibrated for the 315s? If not, even hand calc will be inaccurate.

schu

I'm not sure how you are getting that kind of milage, I lost 1.5mpg when I went up to 315s. I'm betting that you drive on very flat and straight roads. In Alaska nothing is flat or straight, you are always going up or down hill unless your city driving.

Anyway, I would recommend against 315's and 3.73 gears. On my six speed it spaced everything apart way to much. Now in order to pull a heavy load up a big hill I have to run at 65 in 5th or 75 in 6th because the engine really needs 2100rpm to get the turbo going. Shifting around town has become a pain because the engine is slugish and vibrates below 1600 rpm, but you really need to be at 2200-2300 before you shift otherwise you land below 1600 in the next gear.

Next time around I'm going to get 285s. They won't space apart my gears nearly as much and hopefully I'll get some of my milage back.

Squidward

35k miles so far, no tranny problems yet. 17.9 mpg average over the past 2000 miles, 80% highway, 20% city, no towing (Dune season's over).
Averaged 14.3 mpg towing about 4000 lbs during all our trips to Glamis. Never dropped out of OD once on the highway. 35's with 3:73's work just fine around here.

omaharam

Yes, I had it recalibrated. Yes, that was hand calculated as well.

omaharam

The mileage increase is due to the fact that at it was a big reduction in rpms. I had the JWA on level 1, and have a free flowing intake and exhaust. Yes, it was a fairly flat trip. That was also checked from station to station with only one stop inbetween to hurt the average. Still, I am sure it is better than with the shorter tires when I was over 2000rpm.