I had two dragging calipers so I replaced them all with rebuilts. That went fine, but I’m getting no pressure / fluid coming out at all on either rear caliper... Any thoughts? Thanks, SB

 

Two dragging calipers is not coincidence, especialy if they were both front or both rear. I would replace the master cylinder.

 

Thanks. Hey, do you know if the master cylinder is a dual bowl? That is, if the front brakes are working and fully bled but the rear brakes are not, can I drive it to the shop?

 

No. Driving with partially functioning brakes is not safe.

 

Ugh... the local independent Mercedes shop diagnosed the problem, but wanted a small fortune to replace the calipers. I’m sure they’d have found that they needed to replace the master cylinder once that didn’t solve the problem, but since I did it myself, the thing is now beached and undrivable at the bottom of my driveway. Thanks for the help though.

 

Small fortune? They're literally 15 minutes a piece to swap, including R&R of the wheel and brake hose. Maybe add another 20 minutes for flushing the brake fluid. At $150/hr shop rate, it shouldn't have been more than $150 labor to replace the rear calipers and bleed them.

 

Yeah, that independent repair shop wanted $1200. Just not worth it…

 

lol, you could buy a parts car for each caliper and throw away the rest of the cars for that!

 

Alright, so I broke down and bought a hand vacuum bleeding kit from the parts store and I’m pulling nothing but air coming through the hose (that is, I have the thing setup upstream of the caliper)... The reservoir is plenty full, so do I have a bad seal somewhere around the master cylinder?

 

Could a pinhole leak in the car’s vacuum system (not the hand pump) contribute to the difficulty in bleeding the rear brakes? The front brakes both bled fine...