MTH

Following up on the post above, has anybody actually installed OEM 2007 4.10s in a non-2007?

For example, perhaps you picked up a used set off of a non-Rubi 2007 and had them installed to replace the 3.21s in your non-Rubi 2008/2009/2010/2011?

As I mentioned yesterday, I think 4.10s would be best for me to run 33s with a 6 speed. However, the shop I'm speaking with believes non-Rubicon OEM 4.10s would not fit in my 2010. The basis for their position is something about how the OEM "install manual" recommends a different install kit for replacing 2007 R&Ps versus replacing 2010 R&Ps. To them, this indicates some incremental year-to-year change(s) that would likely preclude success.

Does anybody have a different experience or know of somebody who has? Or, alternatively, have you been told the same thing?

shaggy591a

mine were used 4.10s from members on the forum I don't know what what year they came out of. I got one set of rear 4.10s still as i got one rear set from one member and then got a complete set from another member. The only thing I had to get was a new carrier for the front and the carrier for the rear the bolt holes had to be drilled because they were smaller than the new bolts that came with the overhaul kit to fit the gears.

Vincent

Honestly bro, you only want to do this one time because it's expensive! I'm rolling 33" Duratrac's and have 4.88's. It's super awesome yet my plan is moving soon to 35's. Revisit your plans and check out what your future plans are for your JK, cause like almost everyone else you'll want them 35's! So the 4.88's would be optimal! 4.56 are hard to come by anyway. And if you have hills and such, you'll wish for them 4.88's. Get some Truetrac's too while they're opening it up. You'll be impressed!!!

MTH

Ahh, thanks for the info.

I'm pretty sure the 4.10s you have must be from a 2007. As I understand it, after 2007 only Rubis had 4.10s, and Rubi 4.10s won't fit non-Rubis. So yours have to be 2007s.

From your signature it looks like you also have a 2007 Sahara, which would mean that you put 2007 non-Rubi 4.10s into another 2007 non-Rubi. I'd expect that would work.

BUT, it doesn't quite answer whether those 2007 gears could go into a 2010 or some other year. Maybe drilling the carrier would be all that's required.

Anybody put 2007 4.10s into a non-2007?

MTH

No kidding! Yep, I'm going for the TrueTrac in the rear. I was thinking about the front, but was told it would have "adverse handling characteristics." How's yours handle up front?

So you've got 33s on 4.88s with a 6 speed? Is it a daily driver with some highway time? You've got to be spinning 2900 RPMs or so at 70 mph. It's good for you?

Vincent

Ya! You can feel a little difference in the front but nothing bad just a little stiffer but you get used to it quick. Nothing adverse at all man! Best thing I did honestly! Hittin' 70 the rpm's are a bit high but I'll tell ya the ability to get up & go is far worth it! MPG's average city/hwy 15-ish. But I'm all good with it! The Truetrac's front & rear in the snow and on trails are bad ass! No regrets! I Thank 'Planman' for the advice!

MTH

I wanted to bump this to ask whether anybody has a set of 4.10s out of a 2007 (or maybe 2008?) non-Rubi that they're looking to get rid of?

If so, I might pull the trigger on the mystery discussed above and figure out whether older non-Rubi 4.10s will fit into a more recent year's D30 and D44.

In short, I ended up coming into a set of 2010 3.73s for free, so if I can get a set of non-Rubi 4.10s as well, I'll take both sets to the shop and try to get the 4.10s installed. If the 4.10s don't work (as the shop suspects they won't), I can at least have the 3.73s installed so I haven't completely wasted my money on a useless install effort.

PM me if you can help out. If I solve the issue one way or the other, I'll post an update.

PS: As discussed above, I know 4.56s would arguably be better for 33s. But I'd like to keep an overdrive gear on the highway that gets me down below 2500 RPMs, and I eventually plan on supercharging anyway so the 4.56s are really going to be more than necessary. 4.10s would really hit the spot. The current 3.21s are definitely not cool.

sa29560

X2

I have thirty threes on my two door with 4.10s and sometimes it leaves a little to be desired. When I get around to regearing I will probably go as low as possible considering the cost.

MTH

Yeah, I've been kicking around those numbers in my head for awhile now. Add the f/r TrueTracs I want and your getting quite an investment. On the other hand, I'm getting the 3.73s for all of $12 and may find somebody willing to get rid of their otherwise paperweight 4.10s for a similar cost--but yes, you're right that none of that alleviates the install costs.

4.88s for a manual tranmission on 33s (well, 285/70/17, so 32.7s)? I've read enough of your posts to know you've forgotten more than I'll ever know, but wouldn't that put my RPMs up around 3000 at 70 mph? Sounds . . . intense

The reason I'm having a hard time letting go of 4.10s is that I like the idea of keeping 6th gear in what I view as the proper place for an overdrive--that is, an easy on the engine cruising gear for flat expanses of highway. I do 70 highway miles per day, often up around 75 mph and sometimes 80. Would 3000+ RPMs in that scenario not be a little . . . uhh . . . hard on the little 3.8-that-could?

GrimJK

Well I know i am new here but 4.56's are perfect for 33's IMO and i was a process engineer for DANA corp that made the gears for all jeeps