8.25 or 4.10's?

Okay, here is the situation.

My 90 is a DD and trail rig and has the D30/D35 with 3.07's (manual transmission) and I am running 31's right now. I will not want to get any bigger than 33's.

I have an opportunity to pick up either a 97 d30/8.25 with 3.55's or a d30/d35 combo with factory 4.10's.

I am on a limited budget (who isn't) and am torn as to what way to go.

I am leaning towards the 4.10's as I do not know if I will be able to afford to get to 33's anytime soon (if at all), and they will be a huge improvement right away over the 3.07's I am currently running. Plus, I think if I should want to get bigger meats, these should axles should still handle 32's from everything that I have gleaned, correct? And that the 4.10's should be okay with 32's? How would 4.10's with 32's compare to my current 3.07's and 31's?

The 8.25 with the 29 spline is appealing, but do not know if I will be able to, again anytime soon, afford to regear. The 3.55's would be better than the 3.07's too, but I would have to invest in regearing if I do step up to 32 or 33's ever.

As far as cost of the two combo's, both there is only a $50 diff between them.

So, just want some of your opinions. I know a lot of you have been in similar situations, and have more experience, and want to be able to reflect on someone else's thoughts with my own before I decide. I know ultimately it will be my decision, but I do value your thoughts. Thanks in advance.


-Kevin
cyberbackpacker

29 spline 8.25 is what im doing... -Except mine has 3.73 gears and comes with a new gear set for the front.

I also have 3.07 Factory gears....

i would trust an 8.25 more than a d35 any day - AND! the 8.25 has a direct center diff, so one spare axle shaft covers both sides...


My Opinion - take it how you want it
-Ranger

What year is the D35? If it is an earlier one it will hold up to 33's with a light skinny pedal. If not, weld a truss to the D35 and get some cheap spare shafts and run it with the 33's until it breaks.

Now 4.10 with 33's, thats another question, they do well on the street. Offroad 4.10 is still not deep enough, you'll get down the trail, but you will be stalling quite often.

If you went with a smaller tire, like 31's, 4.10 would be ideal. Also that D35 would be able to handle them better.

I'd probably go with the 4.10 axles and just keep your eyes open for a cheap 8.25 with 4.10's down the road ($100-$200). You could then sell your D35 with 4.10's to compensate for the swap. I swapped in a 29-spline 8.25 with 4.10's but then couldn't find a D30 with 4.10's too for less than $450, so I ended up just regearing and locking the front to match the rear, and it cost a lot more.

Go for the 4.10's and 31's. Then when you have saved up enough money, or gathered up enough parts over time, upgrade to a D44 and larger tires.

I would go with the 4.10 gear ratio.

I ran 32's on 4.10 gears (D30/D35 on a YJ) and it was liveable but it was obvious I needed to re-gear when offroad. I now run 31's on 3.55 gears (D30/8.25 on an XJ) and it's not a bad setup but I will definately re-gear before going any bigger.

Either one of those setups on 33's will leave you wanting to do further mods - either bigger axles, lower gears, or optimally - both.

I agree with the above post that recommended the 4.10 D35 and keeping the 31's. Upgrading to 33's only gives you another 1.5" of ground clearance and would be more of a hinderance with 4.10's or 3.55's.

I think the theme here is if you're gonna do it, do it right.

Thanks for all the replies so far. The d30/35 are out of an older xj. However, TWISTEDCOOPER and others, I have been leaning that way (4.10's) because I do believe in doing it right if I am going to do it. Likewise, I am happy with my 31's and do not think I will be going any bigger anytime soon. If down the road I decide I want to run 33's or 35's, then I will bite the bullet and get new axles/gears at that time.

Thanks, and more input is always appreciated.

One other thing, if I do go the 4.10 route and stick with my 31's, I think I will be well suite off-road, but what about highway driving? Thanks again.

I ran 4.10's and 31's with my 5-speed for a while before upgrading to 33's. It's liveable on the highway but I wouldn't hold it at 75 or 85mph for hours on end. 31's and 4.10's are really fun around town and on the trail.