Brake dust shields W116 - PeachParts Mercedes-Benz Forum

kerry · #1 01-20-2008, 12:02 PM

Pulled off a front wheel for the first time today on my 79 SD. There was a sheet metal brake dust shield between rim and hub. Nice feature. It's almost impossible to keep the wheels clean on my 85TD without the shield. Are these shields OE or aftermarket? Any opinions on adding them? Are they available anywhere?

tangofox007 · #2 01-20-2008, 12:05 PM

Dust shields interfere with brake cooling. I would recommend against them. Unless, of course, appearance is more important to you than safety.

kerry · #3 01-20-2008, 12:09 PM

I was wondering about precisely that issue. However, how big a difference is it between adding a dust shield or using the old steel rims with very little space for air movement?

Ether · #4 01-20-2008, 01:43 PM

I have had the dust shields on my 300SD for the entire 7 years of my ownership and have never noted any negative affects to performance.
Shortened rotor life has also been mentioned as a reason not to use them but I haven't experienced that either.

speace · #5 01-20-2008, 02:14 PM

The dust shields are not available from the factory and I am reasonably sure that cooling is the main reason.

I suspect that negative effects of restricted cooling by installing the dust shields varies from car to car, and of course, driving style and climate factors in as well.

I can tell you that when I lost my brakes on my 400E because of the @#% dust shields the PO had installed, I quickly removed them and flung them as far as I could! Believe me when I say THEY ARE NOT SAFE!

It is interesting to note that MB doesn't seem concerned about the heavy buildup of brake dust their cars display, but oh well, they must have their reasons...

There are many various favorite approaches on this site to reducing the brake dust and the ramifications of hard pads/soft pads hard rotors/soft rotors, vented, slotted, kevlar, ceramic. Look around this site for postings. Success varies.

After trying lots of things on my cars I am presently of the opinion nobody has a better rotor than the replacement parts available from MB. My second choice is the Zimmerman line.

Regarding brake pads: Again, this is my opinion based on my experiences. I have had good luck with reduced dust from the PBR Deluxe and PBR Deluxe Plus brake pads. The ceramic Akebono Euro pads are presently top on my list for smooth performance and very low dust, but they are not available for all models yet.

Good luck fighting the dust!

Dust Shields: Just say no!

koolfrog · #6 01-20-2008, 02:26 PM

The 1st generation of dust shields had no opening . the 2nd generation has cooling "louvers" which were supposed to have solved the cooling ( or lack of it) problems .
I have been using them on 3 different cars for the last 15 years WITHOUT any problem.!

speace · #7 01-20-2008, 02:47 PM

Many people have not had problems with the dust shields. Yes, mine had the vents built into them...

I'm just lucky I didn't hit anything when my brakes overheated and went out. It scared me to death! The pedal became mushy and it wouldn't stop.

Everything returned to normal after it sat in a parking lot for a few minutes. It was as if nothing had happened.

That was 7+ years ago. I still have the 400E. All that has been done to the brakes since that day was to remove the dust shields and perform routine maintenance such as periodic fluid change, pads and rotors.

In other words, it wasn't a master cylinder going bad...

I will say that moisture in the brake fluid will make a brake system more suceptable to boiling, and boiling is apparently what happened. My calipers became so hot that the fluid boiled and could not apply pressure.

Was my problem exacerbated by moisture in the fluid? We will never know, but the car was being maintained and periodic flushing of the brake fluid is part of the maintenance process...

t walgamuth · #8 01-20-2008, 03:09 PM

I am surprised that the dust shields caused a catastrophic brake failure. Could you provide more information about that. please?

I have been buying the ceramic brake pads. Hawks sold at tire rack. The reduction in dusting is remarkable.

They have different cooeficient of friction from standard pads so you can't mix them front and rear, and the cost for all four wheels is considerable.

Tom W

speace · #9 01-20-2008, 04:04 PM

More details... hmm.

The brake pads at the time were probably an OEM pad like Textar or Jurid. I had not yet begun my quest for a dustless pad.

I've mostly said all I can think of. I WAS driving the card hard and it was a very hot day. I had rushed home from work to the pool store to purchase chemicals needed to treat a water problem my pool was having. I was pushing it because the store closes early and it is an 18 mile commute in heavy Atlanta traffic. The last several miles of the trip were stop and go.

The brakes failed just before turning in at my destination with only a few minutes to spare. I rushed into the store thinking that I was going to have to buy a master cylinder as well as deal with the pesky pool problem. (No, I don't buy auto parts at the pool store!)

When I came out I noticed there was a lot of heat coming from the front brakes. I think it even smelled overheated! I started the car and tapped on the brakes to see if I thought I had enough brakes to make it the short distance remaining to get home. To my surprise, everything was fine! The pedal felt good, it stopped fine, I could hardly believe it!

The next time I took the car to the shop for service I told them what had happened. They told me that they used to believe in the dust shields, but they found that the cars with them were experiencing premature brake wear and took them off. The fluid was flushed as part of maintenance and I never saw the problem again.

A few years later my then teen-aged son told me that it had happened to him previous to my encounter, but he didn't want to tell me about it because he knew he shouldn't have been driving the car as hard as he was that day... A 400E is NOT the car for a teen!

Ok, I was being dramatic above when I said I removed the dust shields and threw them!

I did remove them myself from one of my other cars!

t walgamuth · #10 01-20-2008, 04:51 PM

Thanks. That surprises me that they would get that hot, but clearly that is what happened to you.

I like to use the phrase "throw it over the hill". It is one I got from my dad. I have never Actually thrown anything over the hill (though I have on occasion thrown things, usually regretting the tantrum after I break something that was previously unbroken). Instead I usually resort to casting obscenities to the wind.

Tom W