How do I change the front rotors - PeachParts Mercedes-Benz Forum

newbie1985 · #1 11-23-2005, 08:27 AM

I have a 1985 300SD and need to change the front rotors. I have never attempted this before and need to know step by step how to do it. The repair shop has quoted me an estimated of way over $800.00. Seems excessive to me and want to do it myself. Any help is appreciated.

pbrennan10 · #2 11-23-2005, 08:35 AM

This might help
http://www.mbnz.org/forums/forums/thread-view.asp?tid=1187684

It's a fairly universal process i think.
Remove wheel
Remove caliper holding bolts (2)
Remove caliper and break pads
Hold caliper up with wire or something.
Remove caliper mount (2 bolts)
Remove rotor with bolt in the front of it
Pull rotor off

dlssmith · #3 11-23-2005, 10:16 AM

For $800 they should come get the car, fix the brakes, cook dinner, clean your bathrooms, and mow your lawn.

sbourg · #4 11-23-2005, 10:32 AM

Replacing the actual rotors is the easiest part of most brake jobs (NOT on a '90 Honda Accord, though). Only caveat is to make certain the mating hub surface is absolutely immaculate.

However, there are plenty of ways to screw up in the rest of the brake job, as I assume pads will be replaced as well, and must in any event be removed before pulling the caliper. If this is a first, I recommend having someone with known good experience oversee you, if at all possible.

Steve

softconsult · #5 11-23-2005, 11:05 AM

The post about being cautious and finding someone experienced to oversee you, causes me to reflect back on how I learned to do some of these mechanical repairs.

When I was 16, pretty broke, and my transmission failed (manual overdrive '56 Ford), what did do? I jacked it up, on a cold rainy night and crawled under the car. Unbolted it and let it come down on my chest. I was on a creeper and somehow managed to slide out from under the car. Then I proceeded to dismantle the thing and find the problem. Stupid and unsafe, but the point is that you can figure things out. Internet google searches often yield the answers.

Rotors are simple. Pads are simple. When you can't get the pads to come out, you figure out that you need to push one or the other out away from the
rotor . You use whatever works for leverage. On pad installation the caliper piston may have moved out again, so you have to carefully push it back a little and not damage the rubber seal. You may want to source and use some MB pad grease for the back of the pads.

You may , depending on the rotor vendor's coating, need to remove the coating with let's say laquer thinner. Then be very careful not to get any grease on the rotor surfaces. Also you need to clean up the caliper bolts and on re-installation apply some blue loctite thread lock fluid.

Then when you are done, it's either going to work or it's not. 99% chance it will work, because it only goes together one way.

Final note. When done, you need to bed the pads. Drive somewhere up to say 30 mph and then gently apply the brakes to a stop. Do this several times allowing the brakes to cool between stops.

Enjoy,

Steve