89 a/t 4WD - differential leak. Rusty w/ no removable cover!

[jes.elless]

Hello all,

Thanks for the great site and community input. Maybe I can lend a hand sometime. At the moment, my van needs some attention and I need help.

Recently purchased a van that sat for a year and half. Runs and drives great, electrical is good overall, but there are a lot of lines that will need replacement. Driving it the past week has led to several fluid leaks: transmission lines (fixed), one leak as yet unknown (tracking it down later today hopefully), but the differential leak is worse than the others.

Basically the fluid is leaking through layers of rust on the back side of the rear differential. Unless there were a way to replace that section where there is often a diff cover on other vehicles... it appears that replacing the axle may be my only option as the axle on my vanwagon appears to be one solid unit.

So, I've scanned though a dozen threads seeking help regarding information on differentials....
The tag that should be on the hump just below the passenger seat is missing, though the rivets remain.
How else might the diff numbers be attained easily?
Can anyone provide a cheat sheet to axle compatibility?
I am very much in favor of switching out the drums to discs if possible as well.

Thanks in advance.

[jes.elless]

So yeah, I'm hunting for an axle at the local salvage yards unless someone has a better idea.
In the meantime some oil leak sealant and maybe some fiberglass applied to the outer area to slow the leak is in order.
Offering a finder's fee of 20%/axle price to anyone who locates a unit worth purchasing within a few hundred miles of Boston.
Guess I'll have to take a measurement and count some splines to know what axle is required.

[timsrv]

If you get me the VIN number I may be able to get you axle info based on that. Tim

[jes.elless]

JT3YR36W3K0010230
i checked the VIN but don't know what to do with the info.
Thank you Tim.

In the meantime I am using a thicker gear oil which slows the leak. Was also thinking of cleaning the rear cover as much as possible then using some JB weld then fiberglassing. Will still likely leak but surely it will not need to be filled every several hundred miles!

[timsrv]

According to your VIN, you have a YR31 LG-PQEA with an axle code of F362 & an A45DF automatic transmission. This translates to a 7.5" ring gear with a final gear ratio of 43:9 or 4.778. Your axle has 2 pinions. Hopefully this information will help with your search. Tim

[Burntboot]

Tim - Wouldn't all the van rear diff housings be the same, just with different gear sets, coil spring versions at least?

Assuming his 3rd member is still good, he could just swap it into a new housing, no?
A lot more work, but might be easier than finding one with the correct ratio.

[timsrv]

Yes & yes. FWIW, I believe all automatic 4wd vans from 87 - 89 would have the correct gear ratio AND the correct mounting. To my knowledge, they never made a 4wd van with leaf springs (I'm pretty sure they are all coil). An axle housing from a 87 - 89 5 speed 4wd van would also work but the gear ratio would be off. The automatic vans are much more common anyhow, so finding a bolt-on axle shouldn't be impossible. I'm not sure if the mounting on a 2wd coil spring van would be the same, but if it is, you could likely use the housing from one of those as well. If you do find one from a 2wd van, be sure to check width between mounts (might look the same but may be dimensionally different). If it comes off a 2wd, it wouldn't be likely for the gears to be the same, but if you can view the axle code tag I would at least check. Jes, you might also want to try one of those salvage yard parts finder sites. Shipping would be expensive, but you might get lucky and find one within driving distance. Good luck. Tim

[joegri]

hi jes i too have had a leaky differential on my 87 4wd van. my van was picked out of a salvage yard and had been sitting in the dirt causing the rust. the fix? i sanded the pumpkin and inserted a few lil screws into the pin holes and coated with jb weld. well were it is maybe 4 years later and its holding just fine. go for the jb fix it works. and its cool to see another van owner in new england

[jes.elless]

Thanks for the input y'all.

Lol, that's funny Joe. I did the same thing to the oil pan. A drip here or there, but overall it worked just fine. It was easy to find the pin holes with the pan off. Holding the pan up against the blue sky gave the impression of a starry night. Used short wide screws, each dipped in high temp gasket sealant. I'll have some free time to try it with the diff. Hopefully it's not too hard to locate the leaky points.

Btw, Over 4000 miles this past month through Maine, NH, and MA, and haven't seen another van on the road. Maybe I'll see ya out there when I hit southeast CT.