rear brakes

[DieselJim]

I just changed the pads and rotors on my rear brakes. One set of pads was totally gone while the other set was half left. I assume from reading other posts that this probably means I have dragging and need rebuilt callipers? These brakes are remarkably simple. My car 85 300SD.

Thanks for any input.

[Wodnek]

That is the likely problem. Sometimes though the rubber hoses close up on the inside either causing a pressure drop to one side or causing one side not to release pressure, causing it to drag.
I would check the rubber hoses. They probably cost almost as much to replace though.
my .02

[P.E.Haiges]

DieselJim,

Loosen the bleed screw on the caliper that had the worn out pads and have someone step on the brake pedal. If the fluid doesn't squirt out readily, the hose to that caliper has probably become restricted. If you are not sure if it might be restricted, try the other side and compare.

Tighten the bleed screw when the brake pedal is released to keep air from getting into the caliper. If the hose has become restricted, it must be replaced.

P E H

[dannym]

The Floating calipers sometimes get stuck. It's easy to split the caliper apart and lube it up. I think a lot of people replace them when they don't really need it.

Just my 2c worth, I believe they should be taken apart and greased every time the pads are changed.

Danny

[P.E.Haiges]

dannym,

What kind of grease do you use to lubricate the calipers? Due to the high temperatured that the calipers are subjected to, I would worry that the grease might burn and make the caliper piston stick worse. I have never heard of anyone else lubricating the calipers.

P E H

[DieselJim]

I would think high temp calliper grease would work? Any specific brand recommended

[DieselJim]

If I am going to split the calliper I might as well get a calliper repair kit and install a new boot and seals why I am at it. I have seen them priced from 12.50 to 15.50 here online for rear brakes. Anyone have experience with rebuilding themselves?

[Hatterasguy]

Rebuilt calipers are pretty cheap for these cars, also I don't really want to learn how to rebuild them. With my luck what could be a short fast project would turn into an ordeal.

I have been told Autozone can get you them for cheap and they come with a lifetime warranty. I have never checked this out myself though. Fastlane also has them for cheap.

[DieselJim]

Any difference between the bendix and ate on autozone? The price at the zone is definitely a good deal.

[Hatterasguy]

The originals on my car are Bendix, but ATE makes nice stuff as well. It probably doesn't make a difference.

[300TD]

I just replaced the brakes all around on my 85 300td (rotors, pads, master cylinder, hoses). I also replaced the two front calipers because one of the pistons was stuck. All of the calipers are fixed with no place to lubricate (don't think I would try). Maybe on a floating caliper one could lubricate the top slide and the lower bolt, but not the piston. My opinion is that you spend the money on the brakes and tires, your life depends on them.

[Brian Carlton]

Originally Posted by DieselJim

If I am going to split the calliper I might as well get a calliper repair kit and install a new boot and seals why I am at it. I have seen them priced from 12.50 to 15.50 here online for rear brakes. Anyone have experience with rebuilding themselves?

I recently rebuilt one of the rear calipers on the SDL. Not a difficult process. Takes about one hour to pull the seals and install new seals and boots.

The most difficult part of the job is to get the pistons out. One pops right out with air pressure. The second won't move at all because of the giant leak where the first piston is now removed. So, you need to rig up two blocks of wood, one of which exactly covers the hole, with two C-clamps and then apply the air to force the remaining piston out of it's bore.

If I could buy a rebuilt at a decent price ($30.00 or so), I wouldn't bother with the kit ($15.00 or so).

[Brian Carlton]

Originally Posted by P.E.Haiges

dannym,

What kind of grease do you use to lubricate the calipers? Due to the high temperatured that the calipers are subjected to, I would worry that the grease might burn and make the caliper piston stick worse. I have never heard of anyone else lubricating the calipers.

P E H

When I take the pads out, I wire brush the machined surfaces of the calipers, where the pads ride, and put a dab of grease along these surfaces. There are four surfaces for each pad. PepBoys sells the grease in a little packet for $1.00. One packet will easily do two wheels.

[dannym]

Originally Posted by Brian Carlton

When I take the pads out, I wire brush the machined surfaces of the calipers, where the pads ride, and put a dab of grease along these surfaces. There are four surfaces for each pad. PepBoys sells the grease in a little packet for $1.00. One packet will easily do two wheels.

I grease Air Handler and motor bearings a lot. I have always used the same grease with never a problem.
I guess you could use axle grease if you really wanted to.

High temperatures have never been a problem. The only time I have ever had problems is when I haven't greased them.

Danny

[lietuviai]

There are about 3 different types of calipers used on the MB's, Bendix and ATE are almost the same except the Bendix type uses a heat shield on the pad side of the pistons. The third type, don't remember the name, is quite a bit different but I doubt you'll have it. The other thing to be aware is that the pistons are right and left sided and have to be re-assembled in a particular way. The raised ridge on the pad side of the piston needs to be turned in a particular direction. There's a special tool with a particular angle that you place on the caliper to point the ridge in the right direction. You can make the tool yourself as well if you know what it looks like.
Also the calipers are difficult to hone since the shop manual specifically states not to split them appart.