2008 CLS 320 CDI - DIY Brake/Disc change?

[Amnesia180]

Hi All,

I have a 2008 MB CLS 320 CDI (automatic with foot parking brake). The dash is displaying the brake pads (and probably discs) need changing.

I've been doing some online searching and have found conflicting information regarding having to hook up the car to a diagnostic system to electronically release the calipers.

I have changed the discs on other cars (Kuga, Qashwai etc), none have been automatic and none have a foot parking brake.

Can anyone confirm if it is just a tyre off, unplug sensor, remove caliper/brake/disc job or whether there is any internal adjustment to electronics required?

Many thanks!

[Stegel]

Amnesia180 said:

Hi All,

I have a 2008 MB CLS 320 CDI (automatic with foot parking brake). The dash is displaying the brake pads (and probably discs) need changing.

I've been doing some online searching and have found conflicting information regarding having to hook up the car to a diagnostic system to electronically release the calipers.

I have changed the discs on other cars (Kuga, Qashwai etc), none have been automatic and none have a foot parking brake.

Can anyone confirm if it is just a tyre off, unplug sensor, remove caliper/brake/disc job or whether there is any internal adjustment to electronics required?

Many thanks!

It’s a straightforward “conventional” pad and disc job - the electronic adjustment procedure only applies to SBC equipped cars (early 211 E classes, I’m not sure if even the earliest CLS ever had SBC). The handbrake operates small drum brakes housed in the rear hub - if you change the rear discs, the shoes need pulling in using a star shaped adjuster accessible through a hole in the disc’s hub, then adjusting outwards within the new disc hub.

[Amnesia180]

Thanks for the speedy response!

Very happy to hear it is a conventional job.

Will I also need to replaced the sensor, or can I reuse the old one?

Just to confirm, no "plugging in" the car to any diagnosis/computer system is required? Will the foot brake need to be released at all to remove any of the pads and/or rotors/discs?

Finally, I think I have a star screwdriver, but do you know the specific type/size (as I know there are several).

Thanks again!

[PositronicRay]

Amnesia180 said:

Thanks for the speedy response!

Very happy to hear it is a conventional job.

Will I also need to replaced the sensor, or can I reuse the old one?

Just to confirm, no "plugging in" the car to any diagnosis/computer system is required? Will the foot brake need to be released at all to remove any of the pads and/or rotors/discs?

Finally, I think I have a star screwdriver, but do you know the specific type/size (as I know there are several).

Thanks again!

It's not a star drive as such, just a little star wheel (like a little cog). You can turn it with a small flat bladed screwdriver, a bit fiddley so watch some YouTube vids before you start.

Yes replace the sensor while your at it.

[Dunit]

As been mentioned straight forward job, It's only on later cars with the electronic handbrake that you need to retract the pistons , Even then it's just a case of accessing the on board service menu and the the cars computer will do it for you.

[lemonslap]

I have done mine on my 2008 S211, easy job.

Couple of things to note:

If you have the sports brake kit (drilled discs), you will need a metal punch (drift) to remove the brake pad retaining pins. These can also seize in place and is worth using a small amount of anti seize where they locate in the calliper on refitting.

Also check the front wheel bearings free play, they are adjustable and makes sense to do it at the same time.

[Stegel]

The pad pins on the non-vented discs in a diesel CLS will need driving out the same way. We’ve had our CLS from new, and the dealer did the first two pad changes. When I came to do the job, the pins were seized solid, and would not drive out. In the end I used a disc cutter to chop the pins into pieces, managed to get each little section out, and installed new pins smothered in ceramic grease to make the next time easier.

[Super Slo Mo]

Are we talking front or rear?

Fronts are as mentioned above, bit more fiddly than the usual but not too hard.

Not done the rears myself, so can’t comment.

[PositronicRay]

Stegel said:

The pad pins on the non-vented discs in a diesel CLS will need driving out the same way. We’ve had our CLS from new, and the dealer did the first two pad changes. When I came to do the job, the pins were seized solid, and would not drive out. In the end I used a disc cutter to chop the pins into pieces, managed to get each little section out, and installed new pins smothered in ceramic grease to make the next time easier.

Not sure smothered is the right thing to do.

[Amnesia180]

Thanks for all the useful info.

The car dashboard just displays as "Brake Wear", I'll check whether it is front or back. However, looking on eurocarparts - they only sell front sensors, so if the vehicle is telling me to change, I assume only the front has sensors? Could be wrong.

again, hopefully the retaining pins don't cause me too much hassle. Is there a certain tool I need to take these out? Or just a bash with a rubber hammer?

Edited by Amnesia180 on Tuesday 21st August 07:27

[Super Slo Mo]

You will need a thin drift/punch and a medium sized steel hammer.

Get a good punch, I had to go to Halfords to get one in a hurry, theirs was cheap and broke before I’d finished the job.

Actually, it is recommended that you replace the pins and the bolts that hold the calipers in situ with new ones.

I didn’t, and it’s been fine, but the pins are cheap and bend quite easily so you may as well.

[PositronicRay]

ECP aren't the be all and end all. Their brake fitting kit didn't, so reused the old. Next time I'll get the fitting kit and or sensors from the dealer, pads and discs too if they'd do me a deal (which they didn't)

[Super Slo Mo]

There’s a Merc dealer on eBay who does the parts at good prices. Not too far away from ECP et al, so worth giving him a shout.
He will put up an eBay ad for the exact items you want.
Mercedesbenzofnewcastle is his shop name.

[Amnesia180]

Great, I'll have a look.
The pins are only about £10 for 4.

I've done some more research and it doesn't seem the rears have a sensor at all - so it must be the fronts that need doing.

Any idea what size bolts the calipers are, I'll get it all ordered up.

[Super Slo Mo]

Not a clue. Mines an estate anyway although probably the same underneath.
Give your Reg to a dealer, or the eBay guy and tell him you want the bolts. He’ll be able to send you the correct ones.

[PositronicRay]

Amnesia180 said:

Great, I'll have a look.
The pins are only about £10 for 4.

I've done some more research and it doesn't seem the rears have a sensor at all - so it must be the fronts that need doing.

Any idea what size bolts the calipers are, I'll get it all ordered up.

Last time I did discs, bolts came in the box (Pagids) although I'd fit the old ones with a bit of Loctite.

[Amnesia180]

Thanks all for the help/replies.

This was a simple, conventional disc/pad change. HOWEVER - only has one sensor (the driver side).

The pad caliper bolts were seized, I managed to get these off.

The disc on the driver side had a threaded screw. This has had to be DRILLED out. The screw was threaded and already rounded (dodgy garage somewhere I should image).

The new ones went on without any problem.

The passenger side was EXACTLY the same. However, that disc was in near new condition.

So to sum up, it took 4 hours to change a single disc and one set of pads. All bolts, screws etc are now copper greased and properly maintained.

What a headache, haha!