gearing ?s

[nagal]

You will need new carriers as Chris said. As far as tools you will need:

Dail Indicator w/ magentic base
Ft/lb torque wrench
in/lb torque wrench
dail calipers - maybe

As far as doing them yourself, I would say maybe. I am doing mine (well I have all the parts and I think all the tools now). From what I have read and been told the key is patenience. Make sure you give yourself plenty of time and do not rush it. If you rush it, you are just inviting trouble.

[drivenhardse]

i personally have not done gears in a jeep but give me a gm 10 bolt and i done a bunches of them paitence is real important, i once thru a set of 4.10's in once in a big hury to make it to the track and broke teeth all the way round the ring after only 3 runs down the track so take your time and you will be fine i soon to be doin it my first time in a jeep real soon

[JeepJunkie]

i wanna get a D44 and work on everything out of my jeep, new gears and hopefully a locker of some sort, and then swap it in.

Prices cant be too high to have gears installed if i took the axle out of the jeep and stripped everything off of it...could they?

[sarah]

i wanna get a D44 and work on everything out of my jeep, new gears and hopefully a locker of some sort, and then swap it in.

Prices cant be too high to have gears installed if i took the axle out of the jeep and stripped everything off of it...could they?

It's 150.00 out this way.

[JeepJunkie]

It's 150.00 out this way.

ok thats about what i was thinking and gears seem to be between 120ish and 150ish so 300 per axle, 600 for both....aww man i want to do these suckers myself

[jmbrowning]

4.10 gears and 30.5" is what the Rubicon comes with. It runs just fine especially with the 4:1 transfer case. I would not go with a more radical ratio than that, unless you plan to trailer your rig over the highways instead of driving it.

My humble suggestion:

31" - 4.10
33" - 4.56
35" - 4.88

[Venomized]

Okay, your 87 XJ sould have on it right now either 195/75R15 or 205/75R15. You want to step up to 31 inch tires and you have 3.07:1 gears.

195's have a diameter of 26.5 inches and 205's have a diameter of 27.1 inches. Most 31 inch tires are not 31 inches in diameter. BFGs are actually 30.7 inches.

Just slapping on the new tires will drop your RPMs by about 300 @ 60 MPH with 3.07 gears when running in your non overdrive transmission gear.

In order to maintain your existing RPMs then you need to step up to 3.55 gears. That is enough of a gear ratio change to justify the gear swap.


G2 = (g1) X (T2) / T1

g1 - current axle ratio
g2 - new axle ratio
T1 - old tire diameter
T2 - new tire diameter

Once you go up in tire size then you will have to compute the speedo gear that you will need as well, just plug the number of teeth on the speedo gear into the equation rather than axle ratios. Have to compute twice if changing both gears and tires at same time.

This info is in alot of different charts as well but don't go by the charts exclusively as not all tire are the same diameter. Brand X tire diameter and Brand Y diameter are not always the same for the same tire size. Close but no cigar.

PM me if I have confused you and you need more info.

[JeepJunkie]

Ok thanks for the info jmbrowning and venomized.

When i bought my jeep it had 235s and i stepped up to 31s which measure about 30.5 some of you that have been on the forum as long as i have may remember i have a 2nd jeep(which is a complete beater) it is an 85 with a 4cyl so im fairly certain it has 4.10 gears. what if i wanted to swap entire carriers with gears and all that to my 87 jeep? both are the 30/35 combo. would that work? would i need any special tools? do i have to worry about backlash and whatever else.

[RangerRick]

Hmmm,
Check your early (rear) axle on the 4cyl. I have run into some NON "C" clip D35's in early Cherokees pre 90 and that would be A HUGE IMPROVEMENT over the "C" clip model axles. If your beater has good axles under it and 4:11's, and then you find it is a NON "C" clip unit, Id swap the whole friggin thing into the good XJ.
'Nuff-said,
Rick

i have a 2nd jeep(which is a complete beater) it is an 85 with a 4cyl so im fairly certain it has 4.10 gears. what if i wanted to swap entire carriers with gears and all that to my 87 jeep? both are the 30/35 combo. would that work? would i need any special tools? do i have to worry about backlash and whatever else.

[nagal]

Even if you swap carriers you'd still have to measure and set backlash. Plus you are not suppose to mix and match ring and pinion gears. So you'd still have to do all the setup.

I would just swap the axles from one vehicle to the other. I do not know enough about XJ if it would be a direct bolt in.

[RangerRick]

Thats why I say if it's a non C with the 4.11s in the 85, just swap the whole assy.

[Venomized]

Thats why I say if it's a non C with the 4.11s in the 85, just swap the whole assy.

I would think that even if it has the clips, make the swap if it will all bolt right in. Sounds like you are set on the 4.11s so swap the entire axles if they fit with or without C-clips.

4.11 gears are not enough to break the axles unless you ae jumping up past 33s and beating on it.

There is a guy on NAGCA with a ZJ running an 8 inch LA lift with 35s and still has the Dana 35 axle and has not had any breakage issues.

[JeepJunkie]

im pretty sure both the axles in my 87(which is what i drive) and my 85(the beater) both have non C clip axles. I think that i am just going to swap the entire axles but....im gonna put the brakes from my 87 onto the 85 axles because they are brand new. If my memory is right the brakes should be exactly the same so they will bolt right up? ill have to talk to my dad this weekend to see if we can go pick up my 85 from his dads house(i need my dads jeep, WJ with the v8, to tow the beater) ill try to get the beater this weekend and ill go from there. thanks for the ideas peoples!

[Roknxj]

i really want to get a d44, but i gotta wait till i start workin again. Luckily my commute to school takes about 5 min.

If you wait and look around you'll find one. I found one with 4.88 and a spool for $500 not bad I think. The guy was using it on an XJ DD.

[Dukes69]

Brett,
If you have some junkyards around you, hit those up. You might get lucky and find an XJ with a D44.