Common problems and solutions HMMWV

[Lothar]

It seems like starting a new thread every time a difficulty arises is a moderator's pain. Perhaps I am wrong and maybe noone will use this but here it is nonetheless. The truck is a 1990 M-998. My current dilemma lies with the rear brake calipers. After noticing some leaking from both sides, I figured I may as well replace the calipers with new ones since just about everything else on the truck has been replaced. After getting them both in, I find that the parking brake no longer works at all. Ran the handle adjustment all the way and it feels like it may be engaging the rotors ever so slightly. No big deal, just needs adjustment. So turning to my handy TMs, I find a nice detail of how and where to adjust the caliper. Unfortunately, the TMs drawings look nothing like my caliper. There is no castle nut used for setting the required gap at the rotor/pad. I know there are other spots along the cable that can be altered but I would like to have an accurate TM, and get this set as it should be. Here are pictures of my TM, the drawing inside and ine of the calipers that came off the truck. And thanks for any help offered.

 

[Lothar]

And in an effort to provide solutions that will hopefully help someone some day...
I am continually amazed at how hard it is for auto parts store workers to find brake pads for these trucks.
Napa part# UP-7531-M is what I use.

 

[NDT]

Ha that is the 1985 version of the TM, the caliper parking brake was just a twinkle in some AM General engineer's eye at that point, the page you pictured is the awful driveshaft parking brake that was in use 1984-89 ish. Find one of the later dated TMs on this site for info on the newer brake.

 

[Lothar]

Thanks for responding. However, here is the exact same directions in the Jan 1990 edition taken from the TM section in our forum.
I am not finding a more recent publication here on our site. Could very well be my shortcoming. I prefer to have a physical book in my hand. If theres anyone that may know which TM I can find the needed information and perhaps where I could purchase said manual, please throw me a bone.

 

[Lothar]

I found a diagram of the correct caliper in TM 9-2320-280-34 dated Jan 1991, so surely theres more information somewhere.

 

[Mogman]

The TM pictures in post 1 and 4 are of the drive shaft mounted P brake, the pic in post 5 is a front caliper.
I have not been able to find the procedure to adjust the caliper mounted P brake, IIRC it will automatically take up slack as it is cycled, maybe applying the brakes/ P brake multiple times.
Hopefully Retiredwarhorses will comment as I am sure he has dealt with them allot.

 

[Lothar]

Thank you, I appreciate your help. After some more digging I am just going to adust it as I initially thought. I am doubting there is a caliper adjustment needed or that can be made. The whole driveline caliper thing had me all turned around. Would still very much like to acquire a physical copy of the 1990 version of TM 9-2320-280-34

 

[papakb]

What you need are copies of MWO 9-2320-280-35-1 and TM 9-2320-387-24-1 starting on page 7-37. The TM is too large to upload but is downloadable from several places online. Just do a search for them. The MWO details the retrofit of the dual pull brakes that has good information in it and the TM has all the maintenance and adjustment proceedures.

 

[Lothar]

Nailed it! Thank you sir.