I have a 2001 Ram 1500 with the V6 Magnum with a 3.55 gear ratio in the rear end. It has the 5 speed manual trans. I plan to pull a 16' double axle enclosed trailer with the truck occasionally (We also have a Cummins).
I have heard that it would be better to swap out the 3.55's for a 3.92 ratio to get more low end torque for towing. My question is: Can I simply buy a set of 3.92's and swap out the gears? Would the 3.92's make a difference? Where could I find a set of these, and how much would this swap run me?
Or, should I go with an even higher ratio such as a 4.10?

Thanks!

 

gear swap requires a few tools and some experience most people don't have. you can buy a book or video and teach yourself to do it, but unless you have a buddy that knows how to do it, you'll not find much if any experienced help.

you can buy parts, tools, instructions from lots of places, including ring and pinion .com (not sure of spelling).

if you have 4wd, you must change both axles.
IF you could find complete axle housings with the gears you want, you could just swap the complete assemblies. unfortunately, its very very hard to find a set of 4.10 axles. everybody wants them.
If you do this, there's little need to go with 3.92. go ahead with 4.10

paying someone to do this can run about 500/axle in labor, plus 300+ in parts per axle for the gears and bearings, plus another 500+ for an LSD unit. on a 4wd you can blow $2k on this.

 

Welcome to DF.

vaughan pretty much summed it up well.

That V6 will hold you back more than anything else without extensive modifications/upgrades. That being said, you can't just "swap gears". You have to know how to adjust them properly during install, otherwise you're looking at a differential exploding on you later down then road (not exaggerating, they have literally been known to fly apart).

I am doing the same swap you are contemplating, as soon as I find two business days where I don't need the truck. If you have a 4x4, like mine, you have to do both axles. I am paying a guy about $800 to do the swap, and install a LSD in my rear axle while he's in there. I paid approximately $400 for my Auburn LSD that will be installed, and $150 for the gears (they are barely used units I got from guy here on DF a long time ago). So, this project will run me over $1300 total in the end, and I found some good deals. It would have cost me $500 an axle, except my guy misquoted me a cheaper price, but he's an honest fellow and going to honor his misquote.

 

Thanks for the info. My truck is only a 2wd.
As for installation, I would definately have someone else with experience do this for me. We know some people who are mechanics and have their own business, so I might get a discount on labor.
So if I go that route, would it be okay just to buy gears and have them install them, or would it just be easier to find a whole rear end?
And should I go with the 4.10 gears over 3.92's? Will higher gears sacrifice top end or much fuel economy?

 

Depending on tire size, you might actually gain fuel economy. You won't lose much top end.

Larger tires take more muscle to move, or at least getting the muscle to the axles more efficiently. Lower gears (numerically higher) get the power there more efficiently, and may actually help with MPGs.

 

V6 1500 trailer rating is only 3600lbs regardless of gearing & trans.
Not exactly a good tow vehicle (no offense).

Is the V6's diff even big enough to hold 4.10 gears? Dealer brochure Im looking at (98 Rams) only shows the V6 going up to a 3.90 gear set.

 

haha, yeah, it's definately no towing vehicle (The reason we have a Cummins, haha). I just want to be able to tow the trailer if I needed to.

As for the 4.10 gears being too big, I actually didn't think about that. You are correct, the other gear set was a 3.92. So I guess I would be stuck with that unless I got another rear end for the 4.10's.

At least it would be better than the 3.55 ratio.