• Steel Soldiers now has a few new forums, read more about it at: New Munitions Forums!

  • Microsoft MSN, Live, Hotmail, Outlook email users may not be receiving emails. We are working to resolve this issue. Please add support@steelsoldiers.com to your trusted contacts.

M1079 check those hubs!

Awesomeness

Well-known member
Steel Soldiers Supporter
1,813
1,518
113
Location
Orlando, FL
It was 62 degrees here today and at the end of a 3 mile test run, the 3 cool hubs felt darn near the same as before i drove. Meanwhile the hub in question was at least 120 degrees. That is simply too much difference. By comparing all 4 bevels/spiders/shafts on all 4 positions, i found an average of about 20 thousands end-play on each assembly except the one in question. It in turn had almost 5 times as much end-play on its shafts according to the feeler gauges. Through trial and error i simply shimmed the large inner-gear until it mimicked the tolerance of the other 3 positions. But that's not the problem, as even before i shimmed it, the hub in question was still getting ridiculously hot on hot days (couldn't even touch it.) Something is dragging or rubbing now just as it was before, but i cant seem to find what it is. It drives straight as an arrow when letting go of the steering wheel and the brake was still cool. Bearing play is also more than acceptable. I wonder if one side on the lmtv front axial pulls more regularly than the other side. Unlikely i suppose but just a thought.
The 3 cool hubs are what I would expect, and the hot hub is definitely out of place.

I don't think you could realistically heat these hubs enough to eat up that much tolerance. I double checked, and if you had a 1.000" thick steel part, after heating it 100°F, it would grow to 1.00072". That scales with the length of the part, so it's multiplying the original length times 1.00072, for a 100°F change.

I like 319cssb's idea to look for some other issue not related to the hub planetary gears themselves, such as brake heating, or perhaps a bearing dragging. That seems especially true if it was hot before you adjusted shimming.
 
Last edited:

tennmogger

Well-known member
Steel Soldiers Supporter
1,579
543
113
Location
Greenback, TN
Did you check the tension on the wheel bearing while you were in there? A too-tight wheel bearing is a classic cause of spindle heating.

BTW, if the wheel bearing had been over-torqued during a previous reassembly, the result would have been increased play in the gears, a condition you just described.

If you have to back off on the wheel bearing, don't forget to remove shims to compensate.

Wheel bearing tension has come up before and I recall most commenters found low pre-loading on the bearings. Mine were set up hardly more than hand tight.
 
Top