Re: [MV] M37 axle-end studs/bolts

From: Cougarjack@aol.com
Date: Sat May 26 2001 - 15:17:38 PDT


John,
The job is a snap. The axle shaft itself just slip fits into the spline in the differential. Your five studs and nuts come off, then you use the two smaller ones (should be square headed bolts if correct) as jack bolts, by backing off the lock nuts all the way out, then turning the bolts in against the housing until they force the axle flange away from the housing rim. Once you have a gap established, pry carefully with your GIANT CRAFTSMAN PRYBAR WHICH INEXPLICABLY HAS A SCREWDRIVER MACHINED ON ONE END, and the shaft with flange will pop right out. You might lose a few drops of grease. You can do all this with the weight of the truck still on the ground. Once you have the axle out, you'll see what needs to be done. One note: A very small number of early M37 rears were equipped with conelocks instead of just the studs. These are hardened steel cones which fit around the stud and are recessed into a countersink in the flange. From the outside, they look like washers. If you!
 encounter these, remove your nu
ts first, then merely give the flange end a wack or two with a big soft hammer, being sure to strike it right in the center. The rebound will cause the conelocks to start backing out, releasing their grip on the studs, freeing the shaft and flange. If your flange is really cemented on tightly, you may have to beat on it quite a bit. The truck understands this and accepts it, and will not retaliate.
If you have any difficulty, email me back and I'll send you some digital pix of the manual pages which cover this operation.
The wheel bearings and seals will not be disturbed by this job, because you don't need to remove the hub from the axle housing. You can even leave the tire on, still on the ground. It won't fall over. Don't take the hub off unless it's necessary, because doing so requires backing off the brake shoes. We all know that once you mess with the brakes, you can NEVER EVER get them to work right again! LOL! (kidding) Check your axle shaft very carefully in strong light for cracks. They tend to crack near the swelling at the spline end, and also near the flange. Look closely at the spline to see if you can detect any twisting. Don't put a cracked or twisted one back in, as replacements are inexpensive. A broken one will usually damage your rear if it goes, and the broken pieces can be a bear to get out.
Last thing...when you turn in your new stud, use some permatex on the threads, both for sealing purposes and to discourage the stud from backing out again. The broken off stud pieces are not usually very tight, so you should not have trouble getting it out. If it requires more than normal effort, get back to me and I'll talk you through removing the hub so you can take it to a machine shop for removal.
It's a good idea to drive the truck a few miles, then come back and retighten the axle flange nuts. That way, if anything has moved, you'll spot it before you break another stud.
Don't get upset if your job developes a leak after a few days. Gear oil is very searching at joints and gaskets, and given the number of joints on an M37 that can possibly leak, and the work it would take to stop them all, it's better to just tolerate small leaks. I like to think of it more like the truck is "marking its territory", rather than leaking. M37's will do that.
Have fun!
best regards,
Jack
In a message dated Sat, 26 May 2001 3:59:49 PM Eastern Daylight Time, John Doyle <jdoyle@writeme.com> writes:

<< Hello all,

One of the studs that anchor the axle cap on the
rear end of my M37 snapped off. I have the replacement
part but have some questions about the replacement.

snip john's carefully written description of THE M37 BROKEN AXLE STUD DILEMMA.....



This archive was generated by hypermail 2b29 : Tue Jun 05 2001 - 23:18:39 PDT