Gear/axle dilema

So here is my "problem" I have a 99 xj 4.0 AW4 with a 8.25. I will be lifting it soon (have everything figured out except claytons/CRS) and want to run at least 33's and probably 35's at some point. Now I have a buddy who will sell me his dana 30 with 4.56's and ARB for 600. So do I pick this up and hope that it will run fine with 35's (from what Ive seen this isnt the best of ideas, but I dont know if people are saying that for trail xj's only) once I gear the rear or do I bag it get a 8.8 and gear with 4.88's and spend more money in the long run locking it. If anyone has ran this setup (4.56's) and 35's what do you think. I tried to be as clear as possible but what Im getting at is the cost to benefit ratio of getting a decent deal on the front end and living 4.56's or taking my time and running 4.88's with maybe just the rear locked. Any input would be extremely helpful I need to let my buddy know if I want his frontend on monday. Thankx to all in advance.

Well first of all is your D30 LP or HP? I keep forgetting the year in which they moved to LP.... if it's LP definately take it! You can always regear later but this way you are set for a while and you still have your old axle for some spares (shafts, diff cover and so on).
On the other hand if you're HP, it's still not a bad deal. The big question is when are you planning to go to 35's? Maybe by then you will build a whole new set of axles (just food for thought) and for now you'll be good with 4.56's? And maybe you will hang on to 4.56's and get 4:1??

Good question that I dont know how do you ID it. I forgot to mention that the 30 with the arb is from a YJ, I dont know what year. My buddy at the landcruiser shop had planned on just pulling the locker and gear out and installing it in the my stock axle rather than fabing everything up.

As far as when I plan on running 35's I might want to run them as soon as its in the air. I would really like to hear from someone that has ran 56's and 35's. My biggest problem is that I havent seen but one XJ running bigger than 32's and its got like 8-10 lift with bushwackers and 36's and I dont want to go that big or have BW's so I dont have a whole to compare to other than pics which dont do justice in my opinion.

Kejtar said:

Well first of all is your D30 LP or HP? I keep forgetting the year in which they moved to LP.... if it's LP definately take it! You can always regear later but this way you are set for a while and you still have your old axle for some spares (shafts, diff cover and so on).
On the other hand if you're HP, it's still not a bad deal. The big question is when are you planning to go to 35's? Maybe by then you will build a whole new set of axles (just food for thought) and for now you'll be good with 4.56's? And maybe you will hang on to 4.56's and get 4:1??

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I think you have that backwards: high pinion is more desirable than the low pinion (shaft angle, strength, clearance, etc.).

$600 for all that is a great deal. Considering a ARB new is around $600...

r@m

Root Moose said:

$600 for all that is a great deal. Considering a ARB new is around $600...

r@m

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I agree...I wish it was closer to me...I'd jump on it if I was you.

Root Moose said:

I think you have that backwards: high pinion is more desirable than the low pinion (shaft angle, strength, clearance, etc.).

$600 for all that is a great deal. Considering a ARB new is around $600...

r@m

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Actually I was talking about hte one in his jeep and working under the assuption that the one he's buying is HP

I’m running 35” MTR with 4:56 as a daily driver and it’s OK. I live in the mountains (Lake Arrowhead area) and when going up hwy 18 I can drive around 65 MPH and some times I wish I had lower gears to pull the hills a little faster, not that 65 MPH is bad in a lifter XJ but, I’m used to going as fast I want in my Cobra. Off-road it’s great since I have an Atlas and has low 4.3 transfer case. I would recommend going as low as your axel will allow you to go.

Xman

Xman, how was it in 4 low without the atlas I cant afford to do that one for awhile.

Do you have an auto, or manual trans? If your auto, I say go for it and get a Tera-Low sometime in the future. A manual is a different story. You will want to go deeper than 4.56 with 35's. I run the AW4 with 4.56's and 35's and it's alright. Downshifts a bit on long grades but its great on the trail and around town. The father-in-law has the same set up in his TJ, but he has the AX15...we will be re-gearing his to 5.13's next week.

wannabe said:

Xman, how was it in 4 low without the atlas I cant afford to do that one for awhile.

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Not bad, but to high for a AX-15 manual Trans IMO, depends how much rock crawling your going to do. Before my XJ I had a 68 CJ-5 with 5:38 and a SM 465 Trans running at 87:1 in low range which I liked with my 33” tire.

Cherokee w/o Atlas, 4:56, NP231 and AX-15 was (48:1)
Cherokee with Atlas, 4:56 and AX-15 (75:1) closer to what I was used too.

Xman

Thankx for the input guys, keep it coming.
Logdog. I have an AW4 just like you, so you think its not that bad or what. Sounds like its not that big a deal to you. I dont drive much on the highway except to the trails otherwise its around town. The only problem is just wondering if i need to go lower cause that means regearing the front and getting a whole new rear and gearing it, would like to save 500 bucks.

Feels a bit lower than stock. If youre not doing a lot of highway, then go with it. BTW, I'm gitt'n bout 22-23 mpg with this setup.

You dont think that it would be necessary to go through the trouble of getting a new rear and gearin with 88's. Also what exactly does the tera low do, is that a 4:1 conversion or does it just free up the front end, I will be running an ARB in the front.

Well...if you got an extra "$500" then yeah, go with the 4.88's. If you don't, I dont think you will be dissapointed with 4.56. The tera low is a 4.0:1 kit. Tera also offers a 2low kit that disconnects the front end.