Who is towing 10k with 36"tires and 4.10 gears

[daytripper63]

Who is towing 10k with 36" or 37" tall tires and 4. 10 gears? I currently am towing with 3. 73 gears and it sucks on the steep hills/mountains etc and I am wondering how much better 4. 10 gears would be, otherwise I am getting rid of my 22. 5" Alcoas wheels(36" tall) and dropping down to 19. 5s wheels(33" tall)

 

[05mxdiesel]

This isn't a very good comparison but my truck in sig has 35" tires on stock rims with 3. 73s and a 6spd. I've towed 10k or over a few times, no farther than 50-10 miles one way, and the truck has no problems with it, except that I shift a lot between 5th and 6th on highway to keep the egts down going up some smal grades. I would love to have 4. 10s as well to get my ratio back closer to the stock 3. 73 with 35s.

 

[MRosinski]

If possible I would wait till the aftermarket world comes out w/ 4. 56, 4. 88, or 5. 13's. Then you wont even notice steeeeep grades

 

[MRosinski]

Or if $$ permits swap in 4. 10's and a G56 transmission. That would give you a pretty low final drive ratio.

 

[osiris]

i know that you didnt ask what else you could do but have you ever thought about a US gear or perhaps gear vendors? They would be almost the same price as the gear swap maybe a little more expensive, but not only would that help you tow better, but it would also give you better unloaded MPG with a 2nd overdrive. Just a thought

 

[thealaskan]

I would not bother with the 4. 10's... even with 19. 5's I would go up (down) to 4. 56's for a final drive ratio of approx 3. 9. With your 22's and 3. 73's its no wonder you can't pull anything.



I have 3. 73 w/AT on an 05 dually and pulled a 40' 17,000 lb 5th wheel RV from New York to San Francisco. The only problem I had was 40 mph head winds across Texas, Arizona and New Mexico. Cut my mileage down to about 8mpg from a best avg. of about 11or12, but no problem with power. 4. 10's on my stock wheels would have been better, but again, if I go to the 19. 5's I'll do a gear switch to 4. 56 which would be close to perfect for my applications.



Hope that helps

 

[RMarkey]

I run 37's on stock wheels with the 4. 10s. No complains here. I'm sure it would be better on stock rubber but what fun would that be?

 

[daytripper63]

I run 37's on stock wheels with the 4. 10s. No complains here. I'm sure it would be better on stock rubber but what fun would that be?

Running 37s and towing heavy with 37s are too different things my truck runs great when I am not towing...

Are you towing with that combo and if so how heavy?

 

[y-knot]

My honest opinion is that anyone that tows heavy (above 8Klbs. ) should have a 4:10 gear set. i know most here don't because of mileage, but and this is a BUT, if you tow heavy and often the priority should be on towing. The difference between 4:10 in high gear and 3. 73 in high gear is almost a full gear. (4:10 x . 79 =3. 24) So if you had an automatic with a OD gear ratio of . 79 (21% overdriven) the above formula shows the difference (3. 73 x. 79=2. 95).

Plus with the automatic, you have the torque multiplication factor of roughly 40 gain. So with the TC unlocked your 600 ft/lb of torque Cummins now will have 840ft/lb available at the transmission.



I have 33" tires that I use for towing, and 37" tires I use for playing. The difference between the two is the 33" tire has a roll-out of 103. 62" and the 37" tire has a roll-out of 116. 18". The 33" tire has 611 revolutions/mile while the 37" tire has 545. 36. Thats alot of difference, when there is the weight difference. Depending on the brand and style, your 37" tire is right around 100lbs, probably twice the weight of a stock tire. The extra weight is a real acceleration buster, just kills the low end performance. Thankfully you have a Cummins and lots of low end torque, so it isn't nearly as bad as it would be with a gasser, but it still robes power.

Many TDR members live in the plains states, where the country side is bone flat. 3. 73 gears would seem OK in areas like that, but once you get into the mountains or areas with many rolling hills, they fall flat.

Your cheapest fix would be to change tire size for towing, for the best towing results I would change out the front and rear gear sets to 4. 10, and go with a smaller tire for towing. Lugging up the hills in the slow lane is definitely not fun.