Differential slip yoke - very excessive play?

Today I jacked up all four wheels to test a seperate driveline problem, but I found this out.. When I push up on the rear drive shaft at the differential end, I can move the yoke both in and out of the diff, up and down and side to side, enough that it'll make noise. When I rotate the shaft it also sounds very rough - time for a new rear end?

I'd worry more about the in and out than the side play.

Sounds like another case of bad pinion bearings.

I agree, either bad pinion bearings or
a loose pinion nut......

Pinion bearings at the very least - the pinion yoke (at the axle) should not have any notable endplay - unless you're using a dial indicator. I believe sideplay should be just about zero as well (both are accounted for in the "preload" spec on the pinion bearings.)

You're in for pinion bearings, and you may as well take care of your carrier bearings as well (since the carrier needs to come out anyhow) and the wheel bearings (ditto on the axle shafts.) Good news? The gears are probably still okeh, which saves you getting a gearset and setting that up from nothing...

Oh boy.

Could this account for the excessive whiplash I get when I get on and off the gas?

Maybe I'll just buy a new (used) rear axle from a junkyard..

5-90 said:

Pinion bearings at the very least - the pinion yoke (at the axle) should not have any notable endplay - unless you're using a dial indicator. I believe sideplay should be just about zero as well (both are accounted for in the "preload" spec on the pinion bearings.)

You're in for pinion bearings, and you may as well take care of your carrier bearings as well (since the carrier needs to come out anyhow) and the wheel bearings (ditto on the axle shafts.) Good news? The gears are probably still okeh, which saves you getting a gearset and setting that up from nothing...

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Gawd Damn boy! Do you know what you're asking of a newbie? Besides, it's probably not needed. Pinion bearing wear is a common side affect of lifting a vehicle. Pinion bearing wear does not affect the carrier or wheel bearings.

Here's a little bearing "test"
Constant Growl= Wheel or Carrier bearings.
Growl in coast or power = front or rear Pinion bearings.
Slopp in Pinion = Pinion bearings.
Excessive runout could be either inproper pinion depth, bad pinoin bearings, or improper carrier preload, or all of the above.

My bet, from experience, is that the pinion beaings are excessivly worn and need to be replaced. Replace much more than that, and you might was well buy a new Jeep because most of the parts are worn by now

What axel do you have????? If it's the 35, throw it in the scrap pile and get a good junkyard special!! If you have the 8.25 or 44, just get a master kit and rebuild!!

Zuki-Ron said:

My bet, from experience, is that the pinion beaings are excessivly worn and need to be replaced.

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Ya think!!!

It's the D-35. I was thinking about grabbing an 8.8 off an exploder at the junkyard for 80 bucks, but if I do that I need to grab a front axle as well to match the gears.

I dont think I'm going to do anything to the 35.

You'll have to weld new leaf perches on the 8.8. Not sure if you know that or not. Also I believe the pinion is offset on the 8.8's.

And when you speak about grabing a front axle to match the 8.8 gearing, what will you get it from? An XJ with 4.11? Isnt that what the 8.8 uses?

Mind as well just get an 8.25 or another D35. I'd go the route of the 8.25...stock gearing, direct bolt-in, no welding required, stronger than a D35 (yet not as strong as a D44) etc.

My apologies for typing under the influence last night...

I was just pointing out that a total axle rebuild is not called for.
D35's are easy to work on, and a set of pinion bearings and seal will not cost too much. There really won't be too much setup either. Hardest part is getting the old bearings off and the new ones on.

JY axles around here start around $200, so I was encouraging some wrenching, but it sounds as though he is thinking strongly about an upgrade anyway.

As mentioned a D44 or 8.25 is a bolt in swap. The 29 spline 8.25 axles out of a 97 and newer are arguably as strong as a D44.

I don't believe I saw a post stating which transmission option that he has, or whether the gears are stock right now. If an automatic that has not been messed with, the gears should be 3.55. If a Manual, the gears are likely 3.07. A lot of folks with manuals find an old automatic unit and swap out both axles.

As far as 4.10 JY front axles, Generally speaking, the 2.5L Cherokees had those in all years. The 2.8L (84-86) Had either 4.10 (auto) or 3.73 (manual) gears.

Zuki-Ron said:

Generally speaking, the 2.5L Cherokees had those in all years. The 2.8L (84-86) Had either 4.10 (auto) or 3.73 (manual) gears.

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I know you put a "generally" disclaimer on that information, but the only 2.5s I've seen with 4.10s were the 5-speed (AX-5) ones. The 2.5/AW4 combos had 4.56s. Anything after that I have no first hand experience with.

They have 3.07 gears, and the junkyard that offers cheap axles only has 35's. I don't want to even touch this d-35. What's the worst that can happen with worn pinion bearings? the whole axle explodes some day driving down the highway?

Edit: As far as I know, most 8.8's are 3.55's. I could be wrong.

mattbred said:

What's the worst that can happen with worn pinion bearings? the whole axle explodes some day driving down the highway?

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Yes. If it's that sloppy I assume its leaking oil pretty bad too, right? Or is the differential empty by now?

Most 8.8s are NOT 3.55s. Do a search and you shall learn

I'm actually thinking about doing as what was suggested and rebuilding the axle - at least the pinion bearing, crush sleeve, and carriere bearings.

IE a master overhaul kit like this: http://www.quadratec.com/products/52440_104.htm

My question is, what's involved with replacing these bearings? Do I need a case spreader? What about backlash? I've heard that if you mess up the installation of the carrier, your entire axle can explode in short order? I'm not going to pay anyone to do this as that's way out of my budget, so I'd like to do it myself.

Edit: Crap it looks like I need a lot of specialty tools that I can not afford. I don't know what to do, haha.

mattbred said:

I'm actually thinking about doing as what was suggested and rebuilding the axle - at least the pinion bearing, crush sleeve, and carriere bearings.

IE a master overhaul kit like this: http://www.quadratec.com/products/52440_104.htm

My question is, what's involved with replacing these bearings? Do I need a case spreader? What about backlash? I've heard that if you mess up the installation of the carrier, your entire axle can explode in short order? I'm not going to pay anyone to do this as that's way out of my budget, so I'd like to do it myself.

Edit: Crap it looks like I need a lot of specialty tools that I can not afford. I don't know what to do, haha.

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I've partially collapsed a crush sleeve (collapsible spacer) before in an 8.25, I replaced the whole spacer (which at the time was the recommendation). I caught it quick and it didn't seem to damage the bearings any, I ran it for years afterwards. They now say the spacer can be re torqued (reused). Why not give it a try, it's unlikely to hurt anything, unless the bearings start to spall really bad.