Rear Brake Rebuild..

[I6whitejeep]

I am going to be purchasing a rebuild kit for my rear brakes on my 93 Cherokee..

Working with brakes etc is not problem and doesnt scare me. I have replaced pretty much everything on the front brakes myself, but never touched the rear drums myself. So I am just looking for some tips.

Any suggesstions from anyone? I am replacing pretty much everything down to the springs, as of right now, I have no rear brakes, I think they are over-rated..

I plan on needing much MAPP gas too, as there is a lot of rust back there..

[badron]

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I am replacing pretty much everything down to the springs
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If it's an older Cherokee replace/rebuild the wheel cylinder (often over looked) and Master cylinder to.

[Saudade]

I'd suggest you buy a rear brake tool as well. It will allow you to remove and replace the springs much more easily and safely than a screwdriver.

[MagicRat]

Do one side at a time!!
Leave one side complete while working on the other. It will provide a useful guide for how all those springs and levers go back together,
Be sure to replace all the hardware, (springs, adjusters, etc) and remember, the long brake shoes face the rear, the short ones face the front.
Also be sure to manually adjust the brakes before you go for your first drive on the new brakes.

[AlohaBra]

Originally Posted by MagicRat

Do one side at a time!!
Leave one side complete while working on the other. It will provide a useful guide for how all those springs and levers go back together,
Be sure to replace all the hardware, (springs, adjusters, etc) and remember, the long brake shoes face the rear, the short ones face the front.
Also be sure to manually adjust the brakes before you go for your first drive on the new brakes.

I use some hi-temp anti-sieze compund on the contact pads for the shoes...where they touch the backing plate...this will eliminate possible squeak when applying the brakes. I also use some on the automatic adjuster screw threads. (Make sure you clean and screw these back in with the new shoes.) While you are at it, apply anti seize compound to the part where the drum goes on the axle and the lug nut studs.

Good tools are must to avoid struggling. Rears brakes are much more tricky than the front disc style. If you can not get the drum off because the drum is too worn, use the adjuster in back to make the shoes "smaller". You can use wd-40 if the drum is rusted on and maybe a rubber or dead blow hammer to help out. There is a puller you can rent if they are trully rusted on.

[JDPascal]

All good advice from everyone.

Only one problem that I see is the antisieze compound on the wheel/lugnut studs.

The torque spec for the wheel nuts is based on DRY threads as in no oil or lube of any kind. If the factory torque spec is used to tighten the wheels the studs will be over stretched and the wheel nut seats gauled.

If you feel compelled to use the anti-sieze, the torque used to tighten the nuts must be reduced by up to 60% depending on what the lubricant is. The amount of reduction is published but mostly it is a seat of the pants guess in my opinion and I don't think you want to use that kind of a guess to keep your wheels on.

Better to chase the threads with a tap and die and install the nuts dry. They should not rust on the stud if the tires are rotated according to the recommended maintenance schedule

I have used a small amount of the anti-sieze on the surface between the drum and the axle end. If there is too much applied, it will work its way out into the drum and contaminate the brake linings and friction surfaces.

Like AlohaBra says - make sure you clean and lube the adjuster threads and don't mix up the left and the right side parts. If you do, the adjusters will automaticly back off the brake adjustment every time you stop in reverse.

Best of luck with the brake job!!

JD

Originally Posted by AlohaBra

I use some hi-temp anti-sieze compund on the contact pads for the shoes...where they touch the backing plate...this will eliminate possible squeak when applying the brakes. I also use some on the automatic adjuster screw threads. (Make sure you clean and screw these back in with the new shoes.) While you are at it, apply anti seize compound to the part where the drum goes on the axle and the lug nut studs.

[I6whitejeep]

All great ideas... Thanks for your input everyone.. I will let you know how it goes, this Thursday I will be doing it.. I will let you know how it goes, and any tips I can give after my run at it...

[scrap_iron]

Originally Posted by AlohaBra

While you are at it, apply anti seize compound to the part where the drum goes on the axle

Good tip regarding the drums - I had to really wrestle with getting them off a couple of times.
I have been using white grease on the backing plate and adjustment screws but the antiseize compound seems like it would last longer.

[I6whitejeep]

Welp.. this is going to have to wait till next week..

FYI, I got all my parts for under $160.. entire rebuild kit (springs, washer, spacers etc), Adjusters for passenger and driver side, new set of shoes, new drums, and new wheel cylinders... (didnt buy a new master cylinder... save that for another day)


$160 was the cheapest I could find locally.. not bad...

[scrap_iron]

Careful when you take off the brake lines - try to use a fitting wrench so you don't strip the ouside of the brass fitting that goes into the wheel cylinder. When I replaced the front calipers on my 88 they stripped and I had to go for new brake lines

[tech_ed]

DO NOT LUBE or OIL THE LUGNUTS! If you do, you run the risk of losing a wheel at speed and killing yourself and perhaps others.
Ed
web/gadget guru

Originally Posted by JDPascal

All good advice from everyone.

Only one problem that I see is the antisieze compound on the wheel/lugnut studs.

The torque spec for the wheel nuts is based on DRY threads as in no oil or lube of any kind. If the factory torque spec is used to tighten the wheels the studs will be over stretched and the wheel nut seats gauled.

If you feel compelled to use the anti-sieze, the torque used to tighten the nuts must be reduced by up to 60% depending on what the lubricant is. The amount of reduction is published but mostly it is a seat of the pants guess in my opinion and I don't think you want to use that kind of a guess to keep your wheels on.

Better to chase the threads with a tap and die and install the nuts dry. They should not rust on the stud if the tires are rotated according to the recommended maintenance schedule

I have used a small amount of the anti-sieze on the surface between the drum and the axle end. If there is too much applied, it will work its way out into the drum and contaminate the brake linings and friction surfaces.

Like AlohaBra says - make sure you clean and lube the adjuster threads and don't mix up the left and the right side parts. If you do, the adjusters will automaticly back off the brake adjustment every time you stop in reverse.

Best of luck with the brake job!!

JD

[AlohaBra]

Originally Posted by tech_ed

DO NOT LUBE or OIL THE LUGNUTS! If you do, you run the risk of losing a wheel at speed and killing yourself and perhaps others.
Ed
web/gadget guru

Well...You are right about torque specs on a nut or bolt being dry.
That applies well to an engine or other machinery.

But the wheel nut that I guess I have worked on for the last 30 years or so are nuts with a metal flange or tapered cone on an alloy wheel ( I don't usually do stamped steel wheels). The important thing is to use a torque wrench which is used every time on a lug nut. Also the maufacturer is conservative on the spec of the nut on the stud which on a Jeep is .500 inch (pretty substantial). The torque on an alloy wheel is about 75 lb./ft. You will not stress a 0.500inch stud to failure with these numbers.

Now, I don't use oil on a stud (why should you?), I use one drop of Permatex anti-seize paste to eliminate any rust possibility. Now no compund should get on the flange or tapered cone surface which has quite a bit of friction ( I am not going to calculate it, but it is equivalent to the coefficient of friction of steel on steel of a circumference of a .500 inch stud that is 0.125 in wide). That amount of friction is substantial enough to keep the nut stressed on the stud so that the wheel will not fall off. That is why it is important to use a torque wrench and NOT an air powered impact wrench on lug nuts like "some" tire shops do. I always loosen and retorque my wheels if a shop has worked on it. If you are still skeptical, retorque your wheels as often as you need to convince your self that they are not getting loose. It actually is more important to check your tire pressures.

Since there are about 20 lug nuts per car and I have worked professionally in dealers service centers for over 20 years, I figured I must have torqued about 1000 plus wheel nuts and I have never seen any wheels fall off because of the small aluminized paste that was used on a wheel stud or a wheel screw (such as on VW, Porsche or Audi vehicles...now these will rust and seize in the hub).

The only reason I went into this lengthy rebuttal to this reponse is to dispell a lot of the old "myths" about oil and torque specs, especially on wheel studs.....do not oil the studs but a small amount of an anti rust coating is not going to cause all 5 lug nuts or all of your wheels to fall off ....especially if you will insist on torquing your wheels properly with a torque wrench. Torquing a wheel also requires the knowlege of the proper pattern and the gradual application of torque to seat the wheel properly to the hub and proper centering with the proper cone shaped lug nuts used on Jeep as well as other manufacturer's products.

Now, if you are still skeptical, what do you think of using plumber's teflon tape?? No....really. How about spraying the studs with hi-temp urethane clear coat to prevent rusting?

[I6whitejeep]

Originally Posted by scrap_iron

Careful when you take off the brake lines - try to use a fitting wrench so you don't strip the ouside of the brass fitting that goes into the wheel cylinder. When I replaced the front calipers on my 88 they stripped and I had to go for new brake lines

I thought about this, and picked up some spare break lines, and fittings..

I was supopssed to do this last weekend, but I forgot it was Easter Weekend, so I am tackling the brakes this weekend. I wish the yard wasnt still partially covered in ice, and the other half mudd, or I would do it right in the driveway..