rear axle problem

[tstephenson]

I use a 51 M37 to feed round bales of hay in the winter to my cows. I have devised a lift for the hay on the back of the beast and it seems to handle this service well. I do have to drive over some rough ground but just creep along and enjoy the ride. Recently I have noticed that the small cap screws on the back axle have begone to work lose and a small about of grease is visible. I have had to tighen them three times over the past couple of months. I am afraid to put to much on them so as not to strip them. What is going on. Any sugestions??

Thanks,
Tim

 

[devilman96]

Tim,

It might be the application your using it in, a problem in the hub, or quite simply the cap screws are just starting to fail... Fastners do go bad from being over used, over tightend, etc, etc... Pull the cap and make sure nothing is about to fall out and get a new set of screws to go it in.

 

[doghead]

Are there split lock-washers on the bolts? Maybe try replacing the bolts and lock-washers with new. Not sure if it had them originally but with the correct length bolt, I don't see why lock-washers wouldn't help.

 

[tstephenson]

Yea, I think I will take all the bolts out, clean up the mess, measure for the correct length bolts, replace them all with new including locking washers and see what happens. I do n ot mind looking after them occationaly, I just did not want to tear up the old girl if something else was causing them to lossen up. Thanks for the advise
Tim
M37

 

[73m819]

is both sides working loose or just one side

 

[tstephenson]

Just the passenger side, and it takes a few trips around the ranch
Tim

 

[M543A2]

Tim:
Are the wheel bearings on that side OK? Can you shake the wheel on the bearings with it off the ground?
Don't be afraid to use LocTite on the bolts.
Regards Marti

 

[M543A2]

Tim:
Another thought. I have had this type of axle come loose and before I got to it the threaded holes in the hub had gotten egged out with the back and forth motion. It was hard to make them hold after that. Be sure your bolt holes and threads are good. If not, consider tap drilling and tapping for the next size up bolts.
Regards Marti

 

[CGarbee]

If you are talking about the bolts that attach the axle flange to the hub (six of them per side), they aren't actually supposed to be bolts but are actually supposed to be studs... I have noticed on more than one M37 that I've worked on that the studs have been replace, in whole or part, with bolts... The bolts don't work as well as you can't torque them quite as well. I've also found that replacing the split lock washers really helps as does converting to a locknut...

The passenger side frequently works loose faster, and the tire on that side also will wear faster too. It's related to the power transmission through the truck (rear wheel drive, differences in lengths of the axles), where you end up with more stress on that particular axle/hub/wheel...

Good luck.