Let's see, Gasser V6 manual 3.55, gasser V6 auto 3.73 Gasser 4 cyl 4.10

CRD Auto 3.73

So, if youre a gasser V6 manual you'll probably want to re-gear to 4.10.
If youre a gasser V6 auto maybe not.

If youre a gasser 4 cylinder youre there already.

If youre a CRD (auto only damnit) probably not.

ive been running 265/75/16's for sometime now. i've read several times now that i should re-gear to 4.10's. why? what are the pro's and con's? will i damage anything if i don't?

Where is a cheep place to get gears? Im looking for them bc im going to be switching to 31's here soon.

confused as to why some not and some you should. Anytime you run a larger tire you need (or should) re gear to bring ( whatever engine you have) back into that sweet spot that it has when running stock gears and tires. No matter what you have say with stock 29 inch tires and 3.73s it runs down the road at 70 MPH at 2100 RPM, move to a larger tire say a 32 inch and it drops to maybe 1750 ( just pulling numbers for argument sake) now you are lugging that engine below where it runs the best, no matter if diesel , gas , or moonshine

Because everything is a compromise. I've re-geared five trucks over the years. All with Randy's Ring and Pinion Service (Yukon) gears and ARB lockers.

Everything is a compromise. You have to factor everything into the equation. It makes a difference how big your tires are going to be above stock as to whether it makes since to drop the money to re-gear. It matters whether you have a manual or an auto. It matters what kind of engine you have (I.E. six cylinder vs. four cylinder or diesel vs. gasser)

You dont properly re gear a truck cheaply! Its going to cost over a thousand dollars for good gears, install kits and labor to do it. And if you havent ever done it you shouldnt start now on your daily driver!

For example Im going to buy a CRD KJ. The Limited came with 235/65-16's if I only increased the tire size by an inch or an inch and a half it might not make sense to re-gear because that engine has the torque to move those tires better than either the four banger or the V6.

My point is that you have to factor everything into it. Another example, Im going to have a diesel, you dont wan to re-gear and have that engine running to many RPM's on the freeway. Everything must be considered......

Dont re-gear without thinking about everything.

I want to get some 4.10's to resotre my power and I need better gas mileage like no other.. (average 15mpg)

CRD Joe
I fully realize how much it cost after doing several also over the years and NEVER have I regretted spending the money that it costs, I used to run 38s/40s on everything and they were my daily drivers, so they got used everyday and to regain the power/ fuel mileage that I lost was well worth it in the long run.
Been doing this little 4WD game for over 30 years now, I know what works, what doesn't, whats worth it

Mine was the original 4.10 swap on a 3.7 KJ. I originally went to Yukon 4.10's in the rear and swapped in a 4 cylinder diff up front while running 245/70R16's that were about 29.5".

So one can simply swap the front dif on a 3.7L with the front dif of a 4 banger straight up when switching to 4.10's? Is it simple as a straight swap or are there other modifications involved (other than 4.10's to match in the 8.25)?

Forgive if this seems a dumb question but we all know this is "learn as you go" and, well . . . i'm learning.