Front brake drums on M38A1

[MASH 4077]

How do you remove the front brake drums on the M38A1? I think the drivers side brake is either worn out of needs adjusted, may even need a wheel cylinder. My jeep pulls really hard to the right whenon the brakes.

 

[JGBallew]

Remove the three slotted screws, then pull it off.

You may have to back the adjusters off if the drums are really worn.
Also, it sometimes rusts to the flange of the hub, so a little penetrant and tapping (not bashing it with a sledge) will loosen it from the hub.

 

[MASH 4077]

Ok so if the screws are seized how do you go about gettin' those out?

 

[JGBallew]

Penetrant and spot heat. I use a butane soldering iron with the tip removed. Kroil or PB penetrant. and let it sit a bit. Tapping with a small hammer around the screw countersink helps.
Then use a screwdriver with a wrench bolster, as you can tighten then loosen to break the rust and layers of paint and still apply enough pressure to keep the driver in the slot.

If the heads are really mangled, they're not hard, just centerpunch and use an extractor or LH drillbit to drill them out.

 

[MASH 4077]

Got those out, but I found out I had to remove the axle nuts & all that fun stuff. But it definitely needs adjusted in!

 

[JGBallew]

Got those out, but I found out I had to remove the axle nuts & all that fun stuff. But it definitely needs adjusted in!

You should be able to separate the drums from the hubs, unless they're really jammed on.

They fit snug to the hub, but are removeable.

 

[MASH 4077]

Ok. I couldn't get the drum off the hub. Its probably really rusty behind it. I may try again this weekend. I may be going to the Haspin rally tomorrow. And thank you for your help!

 

[armytruck63]

Many times when a vehicles pulls to one side, the wheel cylinder on the opposite side is leaking and has gotten the shoes wet. My deuce was pulling to the right during hard braking. The driver's side front wheel cylinder was leaking and had contaminated the shoes.

You may want to pull both front drums to check for this.

 

[JGBallew]

Glad to help MASH, good luck with the work.

Seconding AT63, if you have problems with one side, you have problems with both, unless it's a "GET ME HOME!" repair.

 

[jeeplvr247]

I am having the same problem with the rear drum on my A1. I am trying to get to the rear hub to replace it but I can not get these bolts out to save my life. I have been hitting them with PB Blaster for a week and a half. I have tried tapping, scraping paint and rust off, and heating with a blow torch. So far nothing has given me a result. Can I just pull the hub and drum off together? Any more suggestions on getting these bolts out, I would rather not drill them.

 

[NDT]

Get a sharp small chisel (1/4" wide) and insert into the end of the screw slot at 45 deg angle and give it a couple whacks. There are also impact screwdrivers that might work for this. If you think getting these 1/4-20 screws out is tough, wait 'till you try to pull the rear hub!

 

[jeeplvr247]

I have heard the stories about the hub but right now I am still fighting the screws. I got home from work and tried heat and the chisel for about a half hour with no results. I am going to try to get my hands on an impact driver and see how that goes.

 

[jeeplvr247]

Well I broke the flathead on the impact so I guess it is time to get some new bolts and drill out the old ones. What size bit should I use and is it ok to use generic sized bolts or do have have to order specific ones for the jeep?
Thanks

 

[jeeplvr247]

Success! In a last ditch effort before drilling out the old screw I went out and got a bigger and stronger flat head to put on my impact. When I used the impact that you hit with a hammer it did nothing but when I broke out the pneumatic driver and turned up the pressure it broke them free. Upon removing the drum I noticed that it is full of really thick greasy gunk. I am guessing that it is gear grease. Just so I know, if it was brake fluid leaking from the wheel cylinder is it possible that it would congeal over time and get really thick? Below are the tools it took to get it free, I used every one. Also I have a (not great) picture of the aforementioned gunk hanging off the top of the shoe.

 

[NDT]

Congrats. The gunk could be asbestos dust mixed with brake fluid.

 

[jeeplvr247]

I am going to clean everything up and check for leaks but I think it is just axel grease that had pushed past bad seals. That's probably why the bearing failed too. Does anybody have a good line on a place to rent suitable puller for the hub? I planned on getting one from oriellys but it did not fit right. I can also confirm that Advance, Autozone, Napa, and Murrays do not loan out the correct hub puller. It looks like I may have to buy one

 

[MASH 4077]

Have you tried removing the axle nut & pull the hub and drum as one piece?

 

[jeeplvr247]

Have you tried removing the axle nut & pull the hub and drum as one piece?

I have the drum off now. I am just trying to locate the suitable puller for the hub. I will probably just buy one off ebay.

 

[jeeplvr247]

I made significant progress tonight. My universal hub puller arrived in the mail from Ebay so I got to work. I spent most of the night just soaking up paper towels with old axle grease. The old outer seal had definitely been bad for some time so years of grease had accumulated in the drums (pictures included). I am going to put everything back together after work tomorrow. From what I have seen it seems to be pretty straight forward, just coat everything in grease and shove it back together (if I am mistaken please let me know). I was wondering if anybody had recommendations for a good way to clean the new wheel bearing before I put it in. I do not want to damage my shiny new part. I had to include a picture of the new bearing because it is so cool that it came canned!

 

[NDT]

Clean the new bearing? Is it covered in cosmolene? If so use gasoline (outside away from sparks fire etc). Otherwise just uncan it and repack with GAA or moly EP grease. Looks like someone got totally carried away with hitting the grease zerk for the rear wheel bearing.