My dad is toying with the idea of switching his 3.55 out for a 4.10 gear. Has anyone pulled 13-15k lbs with both that can give me a comparison of how different it is. The truck is a 94 2wd reg cab, auto, 100 plate full forward. It is no longer the daily driver and is used towing a 13k 5th wheel camper.

 

It should pull better with the 4.10's in it, and you will notice a difference in engine RPM vs speed. With the 4.10's it'll rev out better in each gear compared to the 3.55's due to the larger ratio. I think there is a 100RPM difference when travelling around 68mph comparing the 2 gear sets, if I remember correctly.

 

i dont know if they make it but 3.73s would be nice

 

there is a 300-350 rpm difference between the two

Been there done that my 3.54's were ideal with heavy loads where i found the problem was with the 5 speed gearing..... swapped ina 6 spd got that 4th gear underneith direct for grades and everything was perfect. when i ran 4.10s with my 5spd i found i was in OD any time over 40 mph which resulted in me being in OD on most hills or loosing most of my speed when i did have to drop a gear and so i ended doing either 40 mph tached out on most grades or in OD heating things up waiting for my OD gear to fall off. 3.54's with 235/85r16 tires pulled a 20k lbs goose neck for alot of years. i ran 4.10s for 30k miles and couldnt wait to switch back to my 3.54's this was in westen montana, idaho, wyoming and colorado for a good chunk of the driving so sharp switch backs were an issue which is where the 6 spd came in to play being able to use more thgan 1 or 2 gears between 40mph and 65 mph helped alot. i think 3.73's would have been a nice 100 rpm jump but i liked 1700-1800 cruising down the highway at 60-65 mph with a loaded trailer and being able to downshift into direct pull 2200-2400 rpm at 55-60 mph and still have 4th gear to use if i needed for the 40mph-55 mph range.

Diesels can be over geared also. locally i had 6%-11% grades that i contended with on average every 2-3 days without any ill effects from the 3.54's ref whitebird pass idaho, losttrail pass montana, lolo pass idaho/montana just for the local ones that i saw every 2-3 days with the GN loaded those are pretty good ones on a bia daily schedual otherwise once a week i was on a grade of 8-11 and even steeper when i got off the pavement into some job sites


good luck hope this helps but i definately wouldnt change even from 3.54's to 3.73s you are only gaining 100 rpm you could make that up in tire size by dropping down a hair. going from 235's to 215's could gain you 200 rpm the equivilent of a 3.90 gear set. i think gear swaps are the expensive end of things that can have ill and long lasting effects if chosen incorrectly

 

If your dad is going to be towing long distances, I would keep the 3.54's he has in it already. The 4.10's will pull better, but like ddestruel said, in the long run 3.54 gears are better for over the road pulling.

 

Even with the 3.55's you will still get plenty of power to the ground, and somewhat better economy. Highway cruising is more pleasant too. At 65 MPH the engine is turning ~1800 RPMs.

 

if is climbing steep grades 75% of the time then get 4:10's if not then keep the others i tow heavy and wouldnt have 4.10 if you gave them to me

 

I bought a 96 last spring with 410's in it and I hate it. Normal driving the the truck is up against the Governor in the first 3 gears and the motor wont pull until you hit over drive. And driving down the road at 65-70 you are out of your RPM economy band. I wouldn't switch them if I were you. I think you will lose more then you would gain pulling .

 

3.73 are available also 4.56 and 5.13 are as well. There is only one 7% grade that we pull and were trying to get up it a little better.

 

i would go 3:73's before even considering the 4.10

 

I think it would be best to just keep the stock 3.54 gears in it. The trouble is not worth what you would gain, in my opinion.

 

I love my 4:10's only thing I hate is when I go driving over the road and I'm in a hurry I wish I had 3.55's but I dont think I would ever give up my 4:10's.......maybe 3:73's but I dont think the pay off would be worth the swap

 

I have 4.10's and will say they are real nice for towing. But I do more empty driving then towing and 3.73's or 3.54's would work much better for me. I lose to much fuel with the 4.10's, the transmission hangs in third gear longer than I like, you can't go as fast on the highway without using more fuel, and you have the increased wear & tear in general.

I have towed the same loads with my grandfather's 01 with 3.54's as I have with my 06 with 4.10's and there really isn't much difference. My 06 holds hill's much better than the 01', but it doesn't bother me either to just drop out of O/D if I want to fly up them. I'd rather have the higher ratio because of the driving I do. But I agree with every one else that for the little that your trying to gain, such a big expense and change is a waste of time and money. Stick with the 3.54's and I think you'll turn out better in the end, unless money is no object, then I would say go right ahead.

 

I say go find you a junk yard rear with 4.10's and swap the whole rear end out. Take a road trip pulling his 5er and see how he likes it. He can probably get a whole rear end cheaper than it will cost to swap gears unless he doing the swap himself.

 

I only towed a 9600 lb gw 5er with my 97 3.54 5spd and the 3.54 was only good for flat roads - I didn't want to use od at low rpm on the hills. My 03 4.10 is in a totally higher league for towing. A lot of guys with Danas went from 3.54 to 3.9 (the lowest without changing the carrier) and loved them. i was about to do that before I found my 03. Craig