Rear disc brake, Golf 4

Hello.
'On my Volkswagen Golf 4 TDI, the following problem occurs frequently:'
The rear disc brakes are constantly sticking and start to squeal after almost every braking event.
I want to verschandeln the brakes and lubricate the guides.
Do you have any tips on how to retract the brake caliper pistons without special tools (like the VW-3272 or Hazet 4970/3)?

Regards,
Gerhard.

Hi,

I bought a hexagonal pipe for this purpose, which is approximately the outer diameter of the brake piston. I then incorporated the profile of the piston into this pipe (using a flexible abrasive and, of course, filing ). You can then attach a corresponding socket from the socket set to the other end of the pipe and turn the piston back using a ratchet.However, even then, the matter is not necessarily simple (assistance recommended).
Have fun crafting!


Greetings from the North Sea.

Andy.

'Why don't you grab a wrench from the toolbox? It's used to tighten the screws that hold the glass in place.'

It fits perfectly with the G3. It should also fit with the G4.

I had the same problem with my Golf!
Reason: The backing plates of the brake pads were painted.
'And rust had accumulated underneath and pushed it outwards, causing the pads to become stuck on the sides within the guide rails. I filed down any remaining paint and rust on the removed pads until there was some play in the guides, then reinstalled the pads. No need to replace the pistons. This happened 20,000 km ago! Now I'll have to replace the pads soon. I did something similar on a Passat recently – in that case, I removed the brake disc, reinstalled and tightened the caliper.'
To reverse the process, I used an old truck wheel cross at the end where the diameter matched, and I carefully ground it down so that two protrusions remained, which fit into the grooves on the piston.
After opening the bleed screw (be careful! Make sure the hose and container are attached!), I retracted/pushed back the piston. But always finish one caliper completely and assemble everything before starting on the next one. Also, retracting the piston requires a delicate touch - the mechanism is very sensitive, and brake calipers are very expensive.
Nachher auf jeden Fall entlüften - geht aber nur in Eigenarbeit wenn der Wagen kein ESP hat. Furthermore, it should...
man schon einige Bremsenerfahrung haben! After the...
Make sure to perform several brake applications until the ABS activates (pay attention to traffic). Also, ensure that the reservoir doesn't run empty during bleeding – air in the ABS system is a real problem!

Andy wrote:

ich habe mir zu diesem Zweck ein Sechskantrohr gekauft das von den Außenmaßen in etwa den Durchmesser des Bremskolbens erreicht. In dieses Rohr hab ich dann das Profil des Kolbens eingearbeitet (Flex und natürlich feilen ).

*warm-up*

I also need to tackle something similar for my Polo soon. Yesterday, I disassembled the rear brake calipers, but unfortunately, I didn't measure the outer diameter of the piston with that cross-shaped profile.
I estimate it's about 30 mm based on my memory, but I want to get a piece of pipe that also engages as far out as possible – without having to disassemble everything again for re-measuring.

Does anyone happen to know the "stamping dimension" of the piston in a 232 mm rear brake caliper?

Hello,
I re-measured the brake retraction distance.
The outer diameter is 39 mm.
I assume the piston is approximately 40mm in diameter.
My part is similar to ebää's.
Brake caliper retraction tool for AUDI, GOLF, and VW, new with warranty. Article number: 250202867502.
Best regards, Jürgen.

w123diesel wrote:

The outer diameter is 39mm. I assume the piston is approximately 40mm in size.

Thank you.

EDIT
Randomly, I found this part at a hardware store .
Since I don't have any precision tools for preparing a pipe, a fitting, or similar items, building a lathe tool myself would have been a long and tedious process anyway. And since I spontaneously liked the product idea, I bought it for about €15: let's see how it works .

So, if you only want to disassemble the brakes to verschandeln them and re-grease them with paste, you actually don't need a caliper spreader because you're reinstalling the same brake pads. You might not have as much room to work, but it has always worked for me.

Unless your brake disc is already severely worn, you shouldn't have any issues with the pads rubbing against the edge (which is less common on the rear brakes).

Otherwise, you don't have to adjust the settings back that far; you can use the flex wrench for that.

I recently bought a brake bleeder from egedöns for about 10 euros; it's not really a bad investment. Eventually, the rear brake pads will need to be replaced anyway, and then you'll need something like that.