Help: 89 XJ Rear End Seized UP

I was camping last week in the wilds of British Columbia and I guess I somehow knocked on something and lost my rear diff fluid. About 500 KM's later, when climbing a long, long uphill paved road, my rear end locked up solid (the entire case was sizzling like a frying pan!). The truck is now at a garage 300 Km's away (I had to get towed back to the nearest town and take the bus home). Could have been a lot worse - I might have lost the axle on one of the remote logging roads that I was on the day before.

I'm having difficult confirming the rear axle configuration. There was no tag on the axle (long since fallen off). The truck is a 1989 Jeep Cherokee LTD (I've had it since new in 89) with the inline 6 and the factory light duty towing package. It's a 4 speed automatic SelecTrack transmission. According to some data sheets that I had sent to me from Jeep years ago for this specific vehicle, the rear axle is a Dana 35C. The gear ratio is listed as 3.5. Does a 35C with a 3.5 gear ratio sound right? I've done some limited Googling and can't find a reference to a 3.5 ratio!

The mechanic is suggesting replacing the entire rear axle with a used one, rather than a rebuild - which I agree with - but the axles are apparently difficult to find used in the ratio I need and he's quoting me $1000 just for a used 35c from Ontario, not including shipping or installation (seems a bit steep to me!). I'm going to try and find one locally and ship it to him myself but I'm not entirely clear on what my options are). Are there other axle options other than a specific one for an 89 XJ? I don't do a lot of 4 wheeling - occasional gravel/logging roads and driving through some snow in ski season so I don't need anything heavier than the original and I have limited to nil fabricating options.

As a side bar, assuming the rear end could be un-seized (apparently there's nothing busted - but the gears seem to be welded together), could I simply unhook the rear drive shaft and drive the truck the 300Km's home on the front axle (so I could do the rear axle swap myself) with the transmission in part time 4WD or is that liable to blow the transfer case and or the front diff? One more thing, there's some very long up and down, paved hills between where the truck is now and home.

As a second side bar, the tow truck driver that picked me up insisted that the truck had to go on dollies (for which I was charged extra) as the 4WD is never really fully disconnected. I was sure that I read in my owner's manual (now 300 Km's away) that a SelecTrack equipped XJ could be towed, front or rear wheels off the ground as long as the transfer case and the transmission were both in Neutral. Is that wrong? Thanks for any advice.

Reply to
89 LTD
Loading thread data ...

Not very likely... The bearings will be toast, gears gone, the case is likely damaged. You need to determine the real ratio of it, either by researching the VIN (which may help), a tag or build sheet, or by measuring the ratio of the front diff (the easiest way...)

Jack up the front (both tires. Spin mark the tires and spin the input shaft until the tires make exactly one revolution (exactly!) while counting the revolutions of the input shaft. You will have a fractional turn, so account for that. 3.5 is not a valid ratio, AFAIK...

Not an option

Good, got a smarter tow operator.

Better safe than sorry.

A 'junk yard' will be your friend, but try eBay and craigs list.

Reply to
PeterD

Hi Peter:

Thanks for your note.

I believe the mechanic found the front axle tag and determined the front ratio is 3.55. This is probably an dumb question but... the front and rears are supposed to have the same ratio, right?

Reply to
89 LTD

On a related note...

With a used rear axel, is it a given, since it's off the truck, to put new bearings and seals in while it's off? How big of a job is replacing the seals and bearings? Thanks for any advice.

Reply to
89 LTD

If not the same, they will be *very* close. But usually the same.

Reply to
PeterD

Depends on the condition of hte replacement unit. If clean, seems in good shape, oil is good and relatively clean, I'd say don't mess with it.

Reply to
PeterD

Agreed. The biggest job, in terms of work, will be getting the brake assemblies swapped over. The lines will almost certainly be a beast to remove from the toasted rear end so a GOOD line wrench is a must.

If the used axle came off recently and the hydraulic ports are plugged, you may be able to use the brake cylinders but I'd pull the cylinders and check them anyway - those things rust in a hurry and I've rarely seen one out of the yard that didn't need at least a rebuild kit. If the ports are left open, count on replacing the cylinders. Cheap insurance.

Reply to
Will Honea

I've found an 35, 3.55 axle locally, but the wrecker says that it's from a

90-94 Cherokee. He says the only difference between the 89 axle and the 90-94 axle is that the axel shafts are held on with 'c' clips, and the rear drums are smooth (as opposed to the original ribbed drums on my 89). He says that the axle is a direct bolt on swap and that the newer axel would be a slight upgrade over what I have now (not sure why - because of the clips?). (I'd have to move to the new drums which presumably means new pads). Does this make sense?
Reply to
89 LTD

PS: He told me the 90-94 differential is the same 'length' as the 89, that is, no drive shaft changes would be required. Does that make sense?

Reply to
89 LTD

That's what happens when you take a crapwagon like a Jeep into real back country

Surprised the thing didn't explode though even if it did with the weak dick Jeep engine it would sound more like a couple of M80s going off

But that's still enough noise to make someone like Billie Gurl to crap his depends

Reply to
Jeep Sucks

The axles will interchange just fine, but as mentioned, check the wheel cylinders for rust. If you want to keep your rear brakes, you'll need to pull the axles on both rear ends, swap brake backing plates and drums. But, if the new units are ok, why change them?

Yes, the advantage of the newer axle is the C-clips. They take the load of keeping the axle shafts in place off the bearing retainers and puts the load inside the differential. I have the non-C-clip axle in my 88 and I'll be installing new bearings, seals and retainer plates less than 5000 miles after the last set I put in.

Reply to
C.L. "Budd" Cochran

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.