C230 - Unusual brake problem - are rear calipers prone to problems?
 

I did a brake job last fall. Replaced all rotors and pads. When I did the rear brakes, I had some problems:

- The single retainer pins were difficult to drive out.
- Both calipers were really rusty.
- On one side, the caliper was so rusty that the replacement pads would not fit into the caliper. I had to reuse the existing pads on that side. It wasn't very worn, about half life, so I reused it and crossed my fingers :eek:

At first, the new brakes were OK, but not great. I felt a slight warp at first. Now, after about 10,000 miles, they're horrible. I have a bad pulsation on the pedal, squeal when I come to a stop. Sometimes, first thing in the morning, they grind a little.

I need to fix something, but what? I was considering replacing the rear calipers. Anyone have advise on where to start? Thanks for any advise!

Don

Answer:
 

I suggest replacing both rear calipers, flex hoses, pads and rotors.

Best guess:
Collapsed flex hoses acting as one way valves and/or both calipers have sticking pistons + the rotors are warped past salvage.

Brake:
http://www.peachparts.com/shopforum/diy-links-parts-category/142411-brake.html


Have a great day.

Is this a problem on the C230s? IF so..is it earlier models or later models..I just purchased an 05.
Thanks

It's been posted elsewhere that the single-pin rear calipers (like on the 05's) tend to squeal unless you replace the rotors when you put in new pads.

However, I'd be surprised if an 05 had problems with bad hoses or sticky calipers. Change your brake fluid often.

More often than the MB recommendation?

Do I detect some Paranoia ? :o
Changing brakefluid every other year is plenty good enough.
Heck,.....most vehicles on the road never see a fluid change in their whole life. ;)

never been burned on a MB..but have on a POS Volvo..just want to watch out for possible problems..thanks Manny..have a great Sunday.

;) ps...very nice occupation..often wondered how you get into that

Psssssst, if my wife ever sees it I'll either be dead or she'll kill herself laughing.
Gotta have some fun. ;)

Wow, great collection of links! I took me all morning to read through them.

It sounds like you're pretty convinced that the rear brakes are the problem. Do I need to do anything with the front brakes at all? Should I get them turned just in case? Thanks again for the help, :)

Don

PS - This is a 1999 C230 - Kompressor

If you installed new rotors at the front ( decent quality ), I don't see the point of getting them turned.
You may want to check ( or have it checked ) the run-out of them.
Front & rear. ;)

55k on the same rotors and pads on mine. No warpage, no squealage.

I'm easy on my brakes. Vented 17" AMG wheels with a big footprint probably contribute to the lack of wear too.

I don't know if those are the same as on my 98 but I did mine last year and had no problems on the install. I did not change the rotors since they had 90% of wear range still there. I used all the correct paste and instructions per AllData. I ended up with some groan when coming to a stop. This lasted about a year. I attributed this to using ATE pads but I don't really know why it happened. That was the only issue though. No rust etc.

Mike

Answer
 

The pistons would not go back in = rebuild calipers.
I replace the flex hoses any time the caliper must be replaced = experience with too many collapsing internally to become one way valves = cheap insurance.
If you can feel the warped rotor = 99% sure the rotors, even if cut will last less than six months with a light foot.

OK, I got the parts from *************** and did the rear brakes:


ATE N1040-110890 Brake Caliper 81.25
ATE N1040-110891 Brake Caliper 79.85
FTE N7000-98698 Brake Hose 20.14
CFW N7000-98698 Brake Hose 25.75
BAL N1000-54215 (2) - Brake Disc 66.72
PBR N1010-113300 Brake Pad Set Deluxe 45.19

The pulsation was significantly improved, but I still get a nasty pulsation when I hit the brakes at freeway speeds and some in normal around town driving, mostly from the front. I'm going to get the front rotors turned today, but I don't know if that will help. Anyone have any other suggestion? Thanks,

Don

Rotors do fail invisibly
 

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Hi Don,

A problem can occur with rotors that does not even show up when they are cold..
The two layers are separated by a series of internal fins (web) which can crack internally due to repeated hard braking which causes heating and cooling.. This cause the braking surfaces
to have bulging separated by thin spots. Often it is only one side that fails in this way..

You could try a new rotor on the side to which the car DOES pull to save money, but the other one might also cause trouble later. it could also be twice the labour to move the new rotor
while trying to figure out which is the bad side.

Good luck..
Ron

Thanks Ron, if turning doesn't fix the problem, I'll consider that next, but wow, these rotors are pretty new. Maybe a different brand next time. I did get the rotors turned this afternoon. The shop said they had some warping, so maybe that's the answer. The picture is before getting it turned. I don't know what the gray spots are about, but maybe those were hot spots?

Don

Gray spots
 

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Hi Don,

I would think that any differences in the surgace after turning, would more than likely be due to
hardness differences which were the result of hot spots..

I am surprised at the amount of rust showing if there are not very old rotors..:vanish:
Have you looked into the availability of a more rust resistant type of metal?
For some reason, some of the Toyota/Lexus products seem to have rotors which do not show
rust after a couple of years use. Maybe a little nickel in the mix was all it took?

Stainless steel would be expensive , but it they did not crack or warp, it might be worth the cost in the long run. If open wheels were on the car, it would shore'nuff look purrty. ::gorgeous:

Good luck with the latest remedy.

Ron

Well, I got the front rotors turned. The tech at the shop said they were definitely warped. They took over a week for the pads to seat completely, but my problem seems to be solved. No more pulsation at all. Thanks again to everyone that helped me on this, I really appreciate it.

Don