Mr.Gearhead

HI all,
I replaced the rotors and pads on wife's 02 ML320. The rotors are Zimmerman crossed drilled with Mintex pads. Everything went on rather easy and appeared to be in working order. I did have to back the caliper pistons back with a C-Clamp to make room for new rotors and pads but that is typical...

Now to my question. I went for a ride and bedded the pads. Got up to 60mph and got on the brakes without locking up and not completely stopping. Did this about 6 times... then drove without really hitting brakes for about 10mins... to let them cool. The pedal felt REALLY low to stop... almost hitting the floor. I parked it once I felt they were cool enough to not have the pads stick to the hot rotor...

Drove it again today and did same bedding process... Pedal felt low but not as low. Still feels mushing and soft. Fluid level is good. My daily driver is a 2006 E350 and even with the SBC the pedal is MUCH MUCH firmer. Is this typically of the ML? My wife drove it afterwards and noted the pedal does feel kind of low. Below 40mph she states is feel better that before... but 60mph or higher it seems to require more pressure than usual... ANYONE have any suggestions? Is this normal? Did I glaze over and not break everything in? The rotors look clean and nice... not glazed at all... THANKS. Anthony

AndrewAZ

Generally the pedal is very soft, but after doing some hard braking it would tense up a little. You may be having a problem with the brake assist, the only thing I can suggest is going to get it pressure tested. Or if you can find a local member here that can meet up with you and you can compare brake feel and swap cars for a bit.

marcelc

A soggy feel to the brakes can sometimes be cured by pressing very hard on the pedal with the engine running and the car stopped.

sosh

Brakes may need to be bled, also the pedal feel may be different as you used non OEM parts.

Mr.Gearhead

Pedal is much better today. Drove it to work to be sure and the pedal feels much firmer. I did have them Zinc plated to prohibit rust... wonder if that need to burn off first.

At 75mph and hitting brakes "spirited"... it stops just fine. Thanks for all the good suggestions. Unfortunately I can't say the cross drilled stops it better than stock as it is not my daily driver, but they look nice even if they stopping power is like stock version. All four rotors and respective pads with two sensors cost $335 shipped. Not bad at all and saved the shop cash for other upgrades. Looking to get a wood wheel now...

cyeung65

Thanks for sharing your experience. I am considering the same mod. Have seen those cheap CD rotors on ebay for half that amount and really prefer the route you chose. Where did you buy from?

As for the soft pedal, I replaced pads and found the same problem. I did bleed the brakes but that only helped slightly. So I would recommend the brake bleeding too. I did not bleed at the master cylinder and ABS pump as some recommend, so will do that too.

I do have a "low" pedal too and suspect that is being caused by my rotors being down to half life (1 mm from min thickness). Does anyone know if these rotors should be replaced?

auto art

is ther a write-up on how to bleed the brakes with abs,or is it the same as non abs brakes?

AndrewAZ

Nothing will make it stop any better the only thing you will improve is the fade resistance meaning you will be able to stop over and over again within consistent distance better than stock.

Mr.Gearhead

This is the place where I purchased them. Shipping is free to lower 48.. so not a bad deal. They are on EBAY, just search ML320 rotors. EBAY name is brakepros... Here is web addy... http://www.designrt.net/. Shipping was fast and product is top notch. Good luck.

Also... one of the easiest brake R&R I have ever completed. The rotors are a little tight to get off... but I just hit the back of the rotor with a rubber mallet a few times... The rears need to be "wiggled" due to the integral emergency brake drum... On a scale from 1-10 and 10 being difficult.. this job was 3...

cyeung65

I just did it the conventional way, farthest valve first. But if anyone has the MB proecdure - esp for the master cyl and ABS pump sequence - please post.

BTW - where is the ABS Pump? Is it the pump in front behind the drivers headlight? It is marked "ESP".

joelas

On my 95 C220, the front discs are at miimum of 11.4 mm and the pads are nearing min at 3 mm. On the rear the discs are well below min at 5.4 and the pads are near new, pedal is fine, feel is excellent and it stops staright and hard if I wish. So I see no problem of running down to the minimum in normal or average service. That is what minimum spec is for. It would be dangerous to run the pads near ninimum when the discs are also below min because the piston might come out past the seal which would mean no brakes. I am gathering knowledge, parts and tools to replace front pads and rear disks as well as caliper seals as 18 years is a long tme for rubberparts.