GLKMM

God Almighty have mercy...
After searching and reading a lot of post about brakes and rotors, I couldn't find procedures about changing the front Brake Pads and Rotors on a GLK !?!
Soooo I got together with some old MBUSA buddy of mine and he showed me the shop literature so I purchased the front GLK Pads and Rotors and changed them my self as followed...
1st-Found good (inexpensive) vendor: www.importec.com
2nd-Purchased front rotors Zimmermann(Much Better Quality)-$77.35 each,
----MB original front Pads set -$71.10,(includes guide rails and 14mm retainer bolts)
----Brake Disc Retainer hex bolts-$1.17 each
Delivery- about 25 bucks to NYC
Tools: 3ton or bigger Jack Stands
2ft 1/2in drive Breaker Bar
2ft 1/2in drive Torque Wrench up to 300ft pounds
1/2in to 1/4in drive adapter socket
1/4in Ratchet
1ft Very thick blade Flat Head Screw Driver or Pry Bar
14mm 1/4in drive Socket
T25 1/4in drive torx socket, but not sure of the actual size must verify first with the Brake Disc Retaining Screw.
Standard Blue Handle Channel Lock Pliers or Similar
Blue (Not Permanent) Thread Locker about $4.00 from any Hardware
Metal Flake Anti-seize Paste, preferably Copper
Some metal wire brush
And the most Important-1 would be the Sears/GreatNeck universal 1/4in drive "Spline Toothed" Socket (about $14.99set)which will loose and tighten the Hex Headed Caliper Bracket Bolts!!! Metric or Standard it don't matter...
Procedure:
"I DO NOT TAKE ANY RESPONSIBILITY FOR DAMAGE TO YOUR VEHICLE OR PERSONAL INJURIES!!! THIS IS INTENDED NOT FOR THE FAINT OF HEART BUT FOR PEOPLE WITH GOOD MECHANIC SKILLS AND COMMON SENSE!!! THE USER TAKES ALL RESPONSIBILITY UPON HIM/HER SELF!!!"

Park the GLK on a level solid flooring preferably concrete and "APPLY PARKING BRAKE AS HARD AS YOU COULD"!!! Depending on which side of the vehicle you'll be working, turn the front wheels away from that side. In another words if you are doing driver side, turn steering wheel all the way toward passenger side and leave there and shut the engine off. this is for ease of work. Take the jack and the stopper chock included with your vehicle out of the trunk. Install the chock behind front passenger wheel and jack-up the front driver side. Make sure to brake loose the wheel bolts before the wheel is off the ground!!! "DO NOT REMOVE THE WHEEL BOLTS BEFORE YOU FULLY RAISE THE WHEEL OF THE GROUND !!!"
Jack-Up driver side place a jack stand with a small 4x2 wood block right where the lower control arm connects with the chassis or use another sturdy point of preference but do not put weight on it use it only for emergency support, do not remove the vehicle jack, you'll do only one side at a time for safety!!! Remove wheel off vehicle. Wedge the Big Flat Head Screw Driver in the middle of the brake caliper opening between the brake pad and the disc and pry out as to contract the pistons on the caliper all the way in. Loose the two caliper to bracket 14mm retaining bolts, hold the bolt guides with channel lock pliers (because they will free spin over and over) and loosen and remove the bolts. Suspend the caliper in the air with bungee cord or wire to the shock absorber spring.
"DO NOT LET THE CALIPER HANG ON THE BRAKE LINE OR DAMAGE WILL BE CAUSED."
Remove the brake disc retaining screw.
Using the Sears/GreatNeck Universal Spline Socket remove the caliper support bracket bolts, make sure you use the breaker bar and HOLD THE SOCKET VERY FLUSH AND STRAIT AGAINST THE BOLT HEAD OTHERWISE IT COULD BE STRIPPED !!! Remove the bracket.
Remove the brake disc and clean the hub with the wire brush. Apply thin coat of the metal flake antiseize paste onto the hub surface, DO NOT COVER ANY BOLT HOLES ! Install new disc and new retaining screw but first apply blue thread locker on the threads of the screw (read instruction on the thread locker's package)torque to 10-15ft.pounds or very tight hand tight with the ratchet. Apply the thread locker to the caliper bracket bolt's threads (about 1/2in along the thread at bottom portion of the bolt) torque the bolts to 110ft.pounds!!! BE CAREFUL TO MAINTAIN STRAIGHT ANGLE AND NOT TO STRIP THE HEAD WITH THE UNIVERSAL SPLINE SOCKET !!!
Install new steel brakepad guides onto the caliper bracket. Install new brake pads (steel plates are pointed away from disc surface and brake material presses flush against the disc). Reinstall caliper with new 14mm bolts, make sure to coat the treads of the 14mm caliper bolts with blue thread locker and hold the bolt guides with the channel lock pliers(the guides should be in upright position but they don't have specific critical orientation). Torque the 14mm bolts to 28-35ft.pounds. Install wheel and hand tight the 5 bolts. Remove the jack stand and lower the vehicle until tire presses against the ground, then tighten the 5 wheel bolts to 110ft.pounds. Remove Jack completely. DONE
NOW...Repeat the procedure for the passenger side, keeping in mind that the wheels will be turned full lock towards the driver side and the wheel chock will be placed behind the driver wheel. Also there is a brake ware sensor wire that you should reuse (be careful separating it from the pad and its socket), unless the brake lining indicator is ON, which means you have to purchase a new one. GOOD LUCK

shotgun_banjo

Too bad MBUSA doesn't have wear and tear coverage. Mercs here in Canada have wear and tear replacement for the first 2 years or first 40,000K which ever comes first. I feel much better now about the extra $ difference between the US and Canadian mercs.

ame

Do you mean Merc.in Canada will replace the brake wear in the first 2 year for free?
I don't get it......

MKenM

It sounds like you spent about $275-$300. Is that about right? Now assuming that you had all the tools or maybe you had to go out and by some of them how many hours did it take you from start to finish? Just trying to figure out if it would be worth my time.

shotgun_banjo

hell yeah! they will replace most wear and tear items including wipers for the first 2 years

GLKMM

$300.00 or about less, and 2 hours slow steady pace! And yes I got the tools. I like to make sure the job is done correct and not by the new kid at the dealer fresh from Lincoln Tech.

shotgun_banjo

next time take pictures step by step or better have it on video.

slk55er

Suggest that before pushing the pistons into the calipers in you should remove some brake fluid from the reservoir. Otherwise it could overflow or squirt onto surfaces in the engine compartment.

GLKMM

slk55er--- Thanks for the suggestion but you take fluid out of the brake system only if anyone had added some before!?! I never opened the brake reservoir, only checked through the side marking on the plastic, when low it could also be an indication of brake pads being at a lower friction material, meaning do not add brake fluid unless when changing the pads you are ready to take some out. Ask me how I know. Usually fluid is added as an emergency precaution only if criticaly low below lower marking or low indicator on the instrument cluster is ON, meaning there must be a possible damage in the system and loosing fluid. Soooo do not remove brake fluid because whatever level pushed into the pistons' chambers it will be the same level going back into the reservoir, when you done with the procedure, fluid should be just at the upper marking.

And again slk55er thanks for the suggestion, it is a good one, to check brake fluid levels while doing the procedure since, like you have said fluid might squirt out of the cap and damage painted surfaces!!! Very good suggestion..

slk55er

Normal pad wear will cause the fluid level to drop and it drops too low, air can enter the system. That is why our maintenance manual says:

Although you may not have added any fluid, your garage may have. In any case, no harm done in at least monitoring the level as the pistons are retracted. I've replaced dozens of pads and I always remove most of the old fluid from the reservoir and then top it off with fresh fluid (in addition to replacing it completely every 2 years and often before each race or track event.)

GLKMM

[/quote] I've replaced dozens of pads and I always remove most of the old fluid from the reservoir and then top it off with fresh fluid (in addition to replacing it completely every 2 years and often before each race or track event.) [/quote]

This is a very very good point slk55er!!! A lot of MB owners out there neglect the fluids and don't change them for a very long time, and with brake system can be deadly.

GLKMM

By the way in my case it was different:
Front pads had so much meat, they looked brand new, but the rotors...oh the crappy MB rotors, 14000 miles scored and burned, 22000 miles-- corrosion and rust to the point that the driver side rotor on the inside race was pealing off and looked like there were layers starting to come off from underneath... Horrible quality. The pads are still usable, I could have mill them down straight and reuse but decided to go with everything new.

Anyways, the topic is ultimately open to suggestions and corrections. Anyone could contribute creativity and criticism, this is for all of us to help each-other and save a buck... Enjoy

shotgun_banjo

do you think a cross drilled or slotted rotor will benefit the glk?

MBRedux

Disc brake repairs on the GLK are actually no different than many of the cars currently on the road since 1980. If you ever changed pads and rotors before, it's basically the same procedure. There isn't much that has changed.

However, on page 15 of your factory service schedule, you'll notice that it is imperative to replace your brake fluid completely every two years or so to keep the system up to spec. In fact, MB fabricated a special DOT formulation for their cars, DOT 4+ (Spec. 331.0) with extra consideration given to the "+". So I would worry more about that than if your fluid will spill over when depressing the caliper pistons.

GLKMM

Changing brake fluid... Yes indeed, but a different procedure. There is no worries here only a technical "HOW TO INFO", and again I am sure many MB owners find it helpful to see it out there and use it as a guide. There are many procedures from changing front headlight bulbs to resetting service on the instrument cluster. There are many who do not know them and ask how to that is why I decided to list it instead of writing;"If you ever changed pads and rotors before, it's basically the same procedure. There isn't much that has changed."
Better Yet wouldn't you be helpful and kind to tell us how to change the brake fluid on the GLK !!!

GLKMM

Most definitely, plus it will give some good appearance...
I would have loved to put cross drilled rotors but did not find any. Plus the sites who list them are extremely expensive... There is a simple procedures for fabricating slotted rotors your self. It was listed by www.Lindseyracing.com .

MBRedux

This is ill advised. Please do not try this on factory rotors.

GLKMM

I most definitely agree on this one... Do not try on "FACTORY ROTORS".

GLKMM

If any one to do this, PLEASE, read more into it and do not ask me for this procedure. There is way more information on it, and mostly comes from british and german forums... A little tricky to be found through USA internet search engines, but if really interested believe me...TONS of info...

GLKMM

P.S."Play nice, I do not tolerate attackers... Use your common sense. If I am writing this it means I do know a lot more then just this... Simply said, I was a MB tech and Enthusiast far longer then my joining date to this forum!"

MBRedux

And even more so on cheap aftermarket rotors. Although they may be performance labeled, these cheap rotors have a low carbon steel compound which will eventually crack and fail. Expect to pay top dollar. When racing, we use carbon rotors that can cost up to $1k each depending on the application.

MKenM

I brought mine into MB at 30,000 miles after talking to my mechanic. He told me that you need some sort of computer devise to use in conjunction with replacing the fluid. Something to do the the ABS function.

Before bringing the car in I was experiencing what I thought was warping from the from rotors which I felt through the brake pedal. It was not that it was the beginning of the ABS function kicking in when I stepping on the brake pedal with some extra effort. After having the brake fluid replaced the vibration disappeared. For me it was a good reason and worth have the fluid replaced.

MBRedux

You all should take note of the pic I posted of true racing rotors. See any "drilled slots"?

GLKMM

Oh wow you top me off again...!!! Now we are talking about racing the poor GLK...
Maaaa man... STOP. Put a hold on yourself, we are talking about a GLK not a top end F1 car. Cross drilled or slotted or both, It will not lower stopping quality it is simply for show. By the way are you a chemical or structural compound engineer? Have you dissected, took structural and chemical samples and compared in a lab to a data sheet or put these so called cheap after markets through vigorous tests?!?
I would not recomend any of this **** to these cars but I do not understand where you get-off with telling people what to do and what not to. If a guy wants cool brakes on his car what is your problem. Again it started with changing brakes to fluid to I don't know what else you will come up with. No one got killed by using them plus any rotor if ridden hard could go KAPUT in several stops around town. Tell me since you are an F1 guy. WHAT KIND OF HIGH QUALITY ROTORS ARE THE ORIGINAL ON A GLK. I guess its time to take a picture and show you the horror of the original MB brakes. THERE WERE CHUNCKS OF METAL MISSING. And it still stopped on the dime. According to you the NOT ORIGINAL EQUIPMENT ROTORS will disintegrate in a flash ?!? I have driven with ZIMMERMANN's crossdrilled for 35000 miles before changed the pads ONLY, and the discs were lightly scored never warped or hot-spotted soooooo RELAX... I have changed thousands of brakes on MBs. Many times we have changed discs to sport package on Cs and SLKs or CLKs on preferred customers, under warranty. So try to relax a little. Guys are having creative mind, not everything was created in a lab... Don't be the opposite to everyone... I've seen your posts...NEGATIVE

GLKMM

Lord OH Lord... I am sooo apologetic, you must be a race driver who drives an F1 around town. Spoken again of this. I bet if GLK comes with an AMG tuned package and a cross-drilled and slotted you will change the tune... Oh I am sorry they are HIGH END slotted and cross-drilled, not like the aftermarket, which will fail in the first couple of brake applications... Benz uses ATE and/or Febi and still uses them... Did you know that they come in cross-drilled and/or slotted versions and also are cheaper than zimmermann-s. We are not talking about made in the east somewhere, they are still made in Germany or USA and undergo tough evaluation standards it is the very same with brembo or zimmermann... By the way the original GLK or MB in general rotors are designed to absorb a lot of the impact on them thus creating a more smooth and luxurious stop and scoring and warping way too much... The AMG are harder steel rotors but still they are not any superior to the aftermarkets so stop with the spitfire towards the after market sector... Driving an F1 car or a fighter jet, still, has nothing to do with a GLK, so please I am begging you with all my heart STOP.