Rear axle tube leaking thru rusted area...repair or replace?

[84FLH]

2000 Mountaineer. 4.0 SOHC. 338,000 miles. Orig engine.

Right (passenger side) rear axle housing badly rusted where the spring perch U-bolts straddle the top of housing. Fluid is weeping through that area, down sides of housing, onto spring perch. Nothing dripping, but the area is plenty damp. Rust was so thick that when I was done flaking it off, the top of the tube was flat in a 2" long area!

Anyone have experience with Jasper reman rear diff assy's?

How about Auto Zone's "Surefire" rebuilt/reman rear diff assy's? They give 3 year warrant.
------

Thought about having hole welded but by time grinding is done, there might be a good sized thru-hole in that area. I guess a form fitted "cap" could be welded in, but that would mean finding a tube same diameter as the axle housing and cutting a section. Where would I get such a tube? Buy a used/new axle housing? Would that even work? Then I'd need longer U-bolts for spring perch.

What about JB Weld? Would torch, MAPP, or butane gas burn enough oil off to allow JB Weld to adhere?
-----

Thanks, everyone

 

[boominXplorer]

Grab an axle from a junkyard

 

[Gary Crist]

You might buy a whole X semi dead on CL cheaper than a diff in a yard....

 

[masospaghetti]

I'd be worried about the remaining strength of the axle housing if the rust is that severe. Even if it's not rusted through somewhere else, how much good material is left?

Replacing the whole rear axle is not procedurally difficult. It's not an "easy" job because the axle is heavy and it takes a bit of time to do. If there's an axle available from a salvage yard, I'd try that first (but be sure you're getting the right ratio inside). Otherwise I don't see why an Autozone axle wouldn't be fine. If there's a problem, swap it out for another one.

 

[donalds]

Get one from the jy and change the oil
Rotate it by hand feeling for bad bearings