New gears

[mattgrant11]

I have an 88 comanche, it has the 4.0 and the stock dana 35 rear end, I have 34's on it just doesn't have the power to really turn the tires like I want, what should I put in it for new gears.

[jpdocdave]

honestly you need to lose the d35, but 4.56 is a pretty good gearing for that, or 4.88, depending on how you wanna use it.

[Pete M]

How much money do you have available for this project?

[Eagle]

My personal preferences (with a 4.0L engine -- move up to more gear with a 2.5L):

 

Stock tires ==> 3.54

 

30" tires ==> 3.73

 

31" tires ==> 4.10

 

32" tires ==> 4.56

 

33" and larger ==> 4.88

 

You should not be running 34" tires with a Dana 35 axle. You won't be doing so for long.

[mvusse]

Despite all the warnings, I am still running a D35 with 33s after 1000+ miles, 4 wheeling trips, and more abuse than I should put it through on a few trails. It's so full of water it comes pouring out as soon as I loosen the drain plug, but as I'm (have been) intending to put that 8.25" that's been in my driveway for a few months now under it "real soon now", I'm too lazy to pull the cover, drain it, and fill with new oil.

 

Still hanging on just fine.

 

Maybe D35 axles really aren't all that bad after all, or I have the one good one out of the lot.

[jpdocdave]

Despite all the warnings, I am still running a D35 with 33s after 1000+ miles, 4 wheeling trips, and more abuse than I should put it through on a few trails. It's so full of water it comes pouring out as soon as I loosen the drain plug, but as I'm (have been) intending to put that 8.25" that's been in my driveway for a few months now under it "real soon now", I'm too lazy to pull the cover, drain it, and fill with new oil.

 

Still hanging on just fine.

 

Maybe D35 axles really aren't all that bad after all, or I have the one good one out of the lot.

 

i wheeled the crap out of my old wrangler w/ 33's and a d35. i never broke anything, its still a turd axle, and i've seen people break them on the street even.

[jpnjim]

I wheeled the D35 in my old XJ for about 5 years (starting in 1995, on 32's).

ooold pics (notice, NO TJ's :D ):

 

Ran 32" AT's, 31" TSL's, and finally old style 31" Goodyear MT's (great tires BTW) on moderate trails around New England.

 

I never broke an axle shaft (wasn't locked tho), but killed a R&P (3 teeth were just missing one day :hmm: ), and another time blew apart a set of spiders.

(1985 3.73 XJ rear, with stronger 87' shafts swapped in)

 

FWIW, both failures happened on the street. :nuts:

 

Neither break left me stranded, but If you're gonna regear anyway,

swap the rear at the same time (= don't spend money on the 35).

[87Warrior]

I recently went from 4.10s to 5.13s on 35's in my 5spd rubi. At 70mph I am turning about 2900rpm in 5th. By-george this is the best thing I could have done for the Jeep. I spent about 1K getting the front and rear geared with all new bearings, seals, and fluid.

 

Since it rarely sees highway travel, I went with the 5.13's. They are deeper than the 4.88s which would have been like a stock configuration. The extra weight and wind resistance warranted the deeper gears.

[Eagle]

But there's nothing deeper than 4.88 available for a Dana 30 front axle. Due to the smaller diff, any more gear would result in a pinion about the size of a Papermate pen refill. Even 4.88 isn't supported by Jeep or by Dana Spicer. To get 4.88s you have to go aftermarket.