'88 Grand Wagon brake job

Bought my rear break parts last month for 86 CJ7, $125.00 got me new shoes, new drums, new cylinders, and spring kit. I've never done brakes before, daughter took first year machanics and neighbour was machanic for 45 years, so I'll do them myself and get them to double check. I just bolted my rear end under my new frame so don't know when they will get done. But I think if like me you bought all the parts and did one at a time so you had the other to go by, it's just a matter of taking apart and putting back together.

Yes, for sure. It takes me about a half hour per side to replace shoes and if needed a new drum. Parts should run less than $100.00. You might want to get a spring kit as well as the shoes. This comes with springs and new adjusters.

When you do them, only take apart one side at a time. There are left and right side parts that can't be mixed, namely the star wheel adjusters. You can open the other side to follow it for reassembly, but just don't take them both off. I know my stuff so took both off one time a bit ago. Well a friend was 'playing' with parts and swapped the adjusters by mistake on me. Figured it out when the pedal kept going to the floor.

I like to coat the adjuster threads and all the pivot points with a skim of antiseize to keep things working right, more than for ease of removal next time.

A digital camera can be your friend.

Mike

Definitely replace the hardware kits at this time. Wheel cylinders too or at least rebuild kits. Then he will have essentially new brakes.

Earle

OK so I took off one wheel today (the one that I was told was the bad one) and the drum is really rusty and the rim edge is broken off in places. It doesn't look that bad but I can tell if you were to drop it on it's edge, it would probably break a few big chunks off.

I went to Autozone to price parts, and I decided to completely redo both sides- new drums, springs, pads, and shoes. Now the weird part. Spring kit and pads are standard, in stock $6 and $22, so $28 so far. However, they show two drums- one is "plain" and is $61 each and has to be ordered. The other is "finned" and is $15 in stock. The picture on his computer is the same exact drum for each, so I don't know how to tell the difference. There are two different brake cylinders. One is for a 7/8" brake line and one is for a 15/16" brake line and he said it won't be stamped anywhere, I have to bring it in. One is $11 in stock and the other is $45 and has to be ordered. The problem here is I drive this car and I'd rather have all the parts when I start rather than disassemble one day and reassemble a few days later.

Anyone know how I can tell which drum and wheel cylinder I have? One solution would be to order all the parts, use which ones I need and then return the rest.

I also bought a cheap brake tool kit at Harbor Freight for $8. I figure I'll only be doing this rarely so why by Craftsman. The tools have no instructions, so I guess I'll be looking for help on the internet.

I redid the brakes on my 85 GW many times. I would advise that this job could take longer than you might think depending on what you find. You should find a way to still get around while the truck is being fixed. You will probably find that it is usually the cheaper replacement parts that are the right fit. (at least in my case). I had the finned drums. Replaced both of them. I also ended up breaking off bleeder screws at times, involving having to get new cylinders. Its easy to take them out and bring them in so you get the right rebuild kits. And don't forget the one-man brake bleeder kit (unless you have two men!).

Fred

That's pretty easy, one drum will be finned the other one will not. I'm sure the pictures in the computer are just a generic picture of a brake drum. I doubt if it makes a difference which one you use. You can measure the inside of the drum to determine it's size.

There

I think you may have misunderstood what was said. The brake line is all the same size, it's the inside bore of the wheel cylinder that is different. The size should be cast into the body of the wheel cylinder. Sometime it may be hard to see while it is still attached to the vehicle. If you pull the rubber boot off one end you will be able to measure the bore with a suitable tool.

One is $11 in stock and the other is $45 and has to be ordered.

One idea would be to try a real auto parts store, such as Napa, were it might be easier to determine whether or not you are getting the right parts for your vehicle.

I went to NAPA today and bought all my parts. The Jeep is chocked and up on jack stands and the first wheel is off. I took the new drum and tried to slip it on just to see if it fit, and it won't go on. I compared it to the old one and it looks the same, but it won't clear the old shoes. I hope it's because the old drum was probably machined and the old shoes were adjusted to fit the larger bore of the old drum. I sprayed brake cleaner over everything real good and I hit the nuts that hold on the cylinder with wd

1. I will begin the project soon. There was no evidence of brake fluid on the old parts. I'm wondering if I really need to bother with changing out the brake cylinder? I hope I can get help from the group when needed.

A tape measure can tell the difference in the drums, just measure the inside edge to edge.

Open the rubber boots on the wheel cylinders and look for fluid. If there is fluid, they are in need of a change, otherwise I leave them.

I will be around tomorrow if you need feedback. My email is valid.

Mike

I just finished the drum brakes on the rear of my CJ7, had my daughter to help, you really need the other persons hand to hold things in place, but other then that it's pretty staight forward, remove and replace. Took us about an hour for first side, 20 minutes for second, shoes, springs and cylinders, but of course I don't have any brake lines on yet to hold things up, will start my new lines tomorrow, I went with premade stainless, so should go pretty good.

Spent part of yesterday tearing down one side. I took digital photos along the way. There are two potential snags.

First, the linkages etc associated with the emergency brake. They were hidden from view by the shoes, so I couldn't really get a good look or a photo of how that all connected. There is a piece of hardware directly hooked to the cable and I just let it hang for now, I didn't see any sense taking it apart from the cable if it isn't necessary.

Second, there is a piece attached to the shoe farthest back...the left shoe when looking at the right rear. I think its an actuator lever? (I don't have my Haynes book with me) Anyway, the book says to make sure not to lose the pivot. Well there's no chance of that since it's looks to be in there too good. The pivot won't slide out, feels more like a rivet. I hit it good with wd 40 and I'll pry it out I guess. The spring kit looks like it has some of these so I'll use a new one if I booger up the old one.

I took the rubber boots off the wheel cylinders and the insides look pristine, so I'm going to go with the old ones.

I like to coat the notch in the half moon cable slider with antiseize to keep the cable moving free, it is the adjuster. If the cable had taken the shape of this and is no longer flexible, I recommend you replace it. It is important that this cable slides easy.

That pin is indeed a rivet. The new one is needed.

Mike

OK so I did one side last night. Everything went OK. I used C-clamps for a second pair of hands. The brake tool kit helped with the springs. Had I known it would be this easy, I'd started doing my own brakes years ago. I didn't change out the cylindars, so that made it easier I'm sure. I did hit a snag though. The new drums are too small. I adhusted the shoes all the way in and the new drum will bareley slide on. I have them in the car plus one of the old ones and I'll head over to NAPA at lunch. I hope they can fix it for me. Also a friend told me that after I'm done I should travel 10' or so in reverse and hit the brakes several times. He said the brakes self adjust but only in reverse. Any truth to that?

When I finished mine the other day, I had about 1/4" of thread left on adjuster to get new drums on. As for new cylinders, it's just 2 bolts and out they come, well that is after you mangle the brake line trying to undo it :) As for backing up to adjust, yes.

Try to loosen the parking brake cable. Sometimes the parking brake cables gets adjusted whne someone doesn't want to pull the drum and properly adjust the brakes. If you look at how the parking brake actuates both shoes you will be able to tell if it is the problem.

I have them in the car plus one

Yes, the brakes self adjust in reverse. You can do this in your driveway, back up and apply the brakes somewhat hard then pull ahead and hit the brakes again and then keep repeating until brakes are adjusted. You can usually feel the brake pedal get higher if they are in need of adjustment.

Sometimes you have to open the brake reservoir cap to get the wheel cylinders to compress so the shoes fit on. The air pressure under the cap will push the little pistons back out.

The other issue can be a too tight emergency brake cable. The e-brake cable will want some slack in it at this point so it isn't pulling on it's levering system. 'Just enough' to stay tight with no lever movement.

You must do a manual adjust through the hole in the backing plate when you put the drums on or the self adjusters might not catch. The cable can be too loose on a new install and needs to be snugged up.

The brake adjusters 'set' when you hit the brakes going forward. Then when you hit the brakes in reverse, the shoes shift, pulling on that cable which turns the star wheel. You need to then go forward and hit the brakes again to re-set them, before another brake hit in the reverse direction will try to adjust them again.

Mike

That's true about the self adjusters. They only tighten in operation though. If the new drums are too tight they won't do anything for that. If you got the drums on at all I don't think that they are too small. I think that you have something not put together right, such as the star wheels not screwed in all the way or the emergency brake cable too tight.

Earle

By brake resevoir cap, are you speaking of the master cyliner cover under the hood?

I never took the emergengy brake cable from the piece it fits to. I just unhooked it from the old shoe and let it hang. Before I started this I took the old drum off and tried to slide the new drum on just to see if it fit and it was too tight. I took both old and new drums to NAPA and they said it's the drum the computer calls for and they all looked both over and said it should fit.