Fix for M1101/2 Hubs Overheating

The military M1101/2 trailers, whether new or old, have issues with the hubs overheating. The issue is a common one and pretty simple to fix. You’ll know whether you have a problem by towing, even empty, a trailer just 10 miles. If you can’t touch the hubs or smell a burning, like a chemical fire you have hub issues. Learn how to fix this in the Expedition Supply M11 do-it-yourself (DIY).

The Source

It’s them, not you! The issue of HMMWV M1101 & M1102 trailer hubs getting super hot happens to many. The root of the issue of over-heating hubs directly comes from the factory over tightening their nuts. First, be sure it’s not an ID10T error and the brakes or parking brake are disengaged. Secondly, the military trailers aren’t build for speed over long distances. They are built to haul over rocky terrain slowly, so don’t be surprised or alarmed the hub are heating pulling that thing long and fast.

There is a theory floating around that the tongue angle, pointed down while towing, causes the surge brake to engage and heat the hubs. We think there is some merit to that from our experimenting with different trucks and hitch heights. Either way, the fix is simple and 30 minutes away.

The Fix

See Hub removal and seal bearing maintenance for instructions on how to remove the grease cap. This will be the hardest part of the job. You can do some real damage to the cap or yourself because it’s a tough one. If you damage the cap, don’t try to reuse it. Many people don’t even bother putting a new one on.

The only other thing you want to remove is the cotter pin. Don’t remove the spindle nut all the way, simply loosen it about 1/4 turn. Replace the cotter pin and be on your way. If you read the official technical manual, they recommend using all new parts; grease cap, cotter pin, spindle nut and washer. Not necessary, but a simple and cheap precaution if you already sense heat issues or smell burnt grease. Check online or local trailer stores for parts. We don’t sell them, sorry.

While you’ve got things open, why not inspect the whole brake assembly and pads?

Check often

The fix mentioned above should take care of future issues for a while if you’re well greased, but be sure to check the hubs often. At least, before a long trip. Additionally, be sure to have tools with you so you don’t get stuck in the backcountry and you’re wife wonders what kind of man doesn’t bring tools.