3.55 gears, d30, 8.25 w/locker on 33's

[rocklandxjer]

you WILL need a carrier up front the locker will be fine...
you WILL NOT need a carrier in the rear

the 8.25 has no carrier break (different sized carrier for different gear depths) therefor the one you have now will work up untill 4.56 which is the limit of this particuar axle.

4.56 and 33s will be perfect. just a bit deeper than the stock feel (ie: stock tires and gearing)

just be willing to spend a lot of $$$ because seeing as you dont know anything about diffs and drivetrain (not a bad thing, i dont either...but i have buddies who do) youll have to bring it to a shop and they charge a lot for this type of work. youll need at least 800-1000 for the gears and install alone

gears front and rear ~300
master install kits front and rear ~140
installation ~200-250 per axle at least
shipping.

have fun with it!

 

[ZomBrady]

you WILL need a carrier up front the locker will be fine...
you WILL NOT need a carrier in the rear

the 8.25 has no carrier break (different sized carrier for different gear depths) therefor the one you have now will work up untill 4.56 which is the limit of this particuar axle.
. . . .

Thanks for correcting my bad info about the rear carrier! I didn't know that there wasn't a break in carrier sizes.

 

[Big Red]

you WILL need a carrier up front the locker will be fine...
you WILL NOT need a carrier in the rear

the 8.25 has no carrier break (different sized carrier for different gear depths) therefor the one you have now will work up untill 4.56 which is the limit of this particuar axle.

4.56 and 33s will be perfect. just a bit deeper than the stock feel (ie: stock tires and gearing)

just be willing to spend a lot of $$$ because seeing as you dont know anything about diffs and drivetrain (not a bad thing, i dont either...but i have buddies who do) youll have to bring it to a shop and they charge a lot for this type of work. youll need at least 800-1000 for the gears and install alone

gears front and rear ~300
master install kits front and rear ~140
installation ~200-250 per axle at least
shipping.

have fun with it!

If you aren't in a hurry...shop around. Try to find someone making a move up to stronger axles. Many people just about give away 8.25 axles, even the ones with 29 spline axles shafts. I saw someone on Pirate4x4 sell a non disco 297 u-jointed dana 30 and 29 spline 8.25 for like $150 or something like that. For a guy going from a disco 30 with 260 u-joints and dana 35, that's quite a cheap upgrade, then get them geared and locked and you have something to work with. If you have the time, shop shop shop before you lay down the big $ getting your axles geared and locked. There is nothing wrong with building up a 8.25, but you might just find a nice built Xj dana 44 with 4.88 gears and detroit for $700-1000 or so ready to bolt in. You could track down a XJ 44 for $350-450 or so, lock it, gear it but you'd be paying for shipping, tax, time to do it, etc etc.
Places to find your XJ stuff: here at .org, Pirate4x4, Craigslist.com, local 4x4 websites etc., friend of a friend. The 30/44 or 30/8.25 is a good nitch, strong and reliable enough for 33's, and can be had for not too much when people want to go hardcore with 44/9" etc.

I'm so tempted to go this route with my 98' XJ dd, eventhough I have a 91' on 37's, 4:1 t-case, locked/geared etc etc. Then I can roll into work with 33's and some lift and stand out from the plain jane stock XJs on the road. Do I need it...no, but it sure is nice if the price is right. While I would lose some MPG with more wind resistence of the taller rig, the gearing should help out with the 33's over 30" tires and 3.07 gearing with the 5 speed.

Troy

 

[twisted_ed]

I just went through everything in this. I put on 32s and had a tranny hunting for gears. I was able to daily drive it, wheel it, etc with no problems other than the cost of gas and agrivation of the tranny hunting and bogging down. I decided to get better axles and then lock and regear them at the same time. After joining a club I was convinced why go to 35s, like said before, its only another inch, mabe two.. big deal. get skids, The guys running 33s were going everywhere the guys with 35s+ were going and with less problems really. So i will upgrade to 33s one day and call it quits. For gearing I picked up a ford 8.8 with 4.10s, though I would leave it at that and gear and lock the front which I thought was a good thing. The club changed my mind. Thanks to a well seasoned wheeler, he pointed out on a hill climb that this cherokee with a front locker will not make it, whereas the one with a rear locker will. Well I was sold on a rear locker and was ready to pop an ARB in the rear. Then i was told why go with 4.10s now and pay fir 4.56s in the future when both axles were going to be torn apart anyways so I went with 4.56s which is good for both 32s and 33s.

But theres a downfall, it costs money. You have to pay for the parts and then the labor, or do it yourself and if you dont know what you are doing its not going to be pretty. So I got a mechanic to help me install them and saved on the labor but the price of extra tools got a little expensive like building a case spreader and the headache. I would say if you want this done ASAP, get a shop to do it.

 

[bigwillxj]

i paid 400 for my gears, install kits, and carrier and the guy is putting them in tonight for 450. im so exicted to have something to look forward to after school tomorrow

 

[Trailbst]

Wow, lots of good info, and bad info.

The hunting tranny, well, put it in 3rd, and drive around 2500-3000 RPM and get some good gas mileage. Just cause you have an overdrive, doesn't mean you have to use it. RPM range is where the gas mileage is, not the gear in the tranny. I run in 3rd with 33s around 2600 RPM and am getting between 17-18 MPG. When I go to the 315/75/16s I'll do the same thing.

Bobnoxious mentioned what he ran. Sometimes not having the gears is better, it allows you to generate wheel spin and get up the obstacle. Sometimes, having the gearing, you put too much power to the ground.

Gearing is nice, but gearing is expensive. Nothing says you can't drive with bigger tires without the gearing. Just have to learn to work with what you have.

My XJ moves just fine with 33s and 3.55s. I cruise down the highway. I just do it in 3rd where the engine is happiest.

 

[Big Red]

Wow, lots of good info, and bad info.

The hunting tranny, well, put it in 3rd, and drive around 2500-3000 RPM and get some good gas mileage. Just cause you have an overdrive, doesn't mean you have to use it. RPM range is where the gas mileage is, not the gear in the tranny. I run in 3rd with 33s around 2600 RPM and am getting between 17-18 MPG. When I go to the 315/75/16s I'll do the same thing.

Bobnoxious mentioned what he ran. Sometimes not having the gears is better, it allows you to generate wheel spin and get up the obstacle. Sometimes, having the gearing, you put too much power to the ground.

Gearing is nice, but gearing is expensive. Nothing says you can't drive with bigger tires without the gearing. Just have to learn to work with what you have.

My XJ moves just fine with 33s and 3.55s. I cruise down the highway. I just do it in 3rd where the engine is happiest.

Sounds good, if you o.k. with losing a gear with too much tires for all your gears then go for it. I just kick down a gear when I want power for passing, slowing down etc, but try to use the highest gear possible to keep my RPMS down and get better MPG. This is with my dd and a manual and 3.07 gears, with my 91' wheeler on 37's my speedo doesn't work so I know how fast I'm going by the RPMs. New gears are expensive so if this works for you with losing a gear to be practical then that's cool.

 

[djblade311]

dammit. :twak:

There is a gear thread that has all your answers. Search.

But yes, go 4.56 for front and rear AT the same time. When you go 35's and want to regain your power, swap the 8.25 for something like a D44, 8.8 or whatever in order to have room for 4.88 or 5.10's.