W124 - should brake calipers be replaced in pairs?
 

Took the 1989 300TE to my favorite mechanic for a couple things, he indicated the front right caliper needs replaced as it is sticking pretty badly.

Ideally, should these be replaced in pairs?

Your $0.02 are welcome.

TIA!

Brian
89 300TE 183,xxx - original calipers all around

had to replace one of my front calipers because the bleed nipple broke off due to excessive corrosion - I just bit the bullet and had that replaced, but MB did not advise me to replace the other one.

however, if you are in the market for a 400e front brake upgrade, then this might be a time to do it.

Calipers are not a wear item - though rarely the seals or boots need replacing - so I see no reason to replace one unless it fails. A sticking caliper can result from dust boot failure, or contaminated or deteriorated brake fluid. It is important to determine the exact cause and type of failure making it stick to evaluate then extent of further damage to the braking system.

In our Honda Accord I discovered a bent slide-bolt for one of the front calipers. That caused both 'sticking' behavior and ineffective braking at that wheel. The caliper was fine - with a new bolt installed. The disk on that side was burned - strange pattern. Apparently the damage had occured during a prior shop job, and would not have been apparent if a simple pad replacement was being done.

Steve

Only the wear components, the pads and rotors, need to be replaced in pairs.

Gilly

I fear I may have overlooked a brake fluid change - any chance new fluid/thorough flush will restore caliper performance?

TIA

Brian (feeling like dolt)

"I fear I may have overlooked a brake fluid change - any chance new fluid/thorough flush will restore caliper performance?"

If the caliper is sticking, the reason should be determined before continuing. The parts involved in a rebuild are cheap - piston seals and dust boots - but labor may cost more than a replacement caliper.

Absolutely the fluid should be flushed, but pay attention to its condition. If it caused deterioration of the piston seal, more problems may yet develop. But, if the dust boot ruptured, allowing contaminants to score the caliper bore, simply replacing that caliper will take care of your problems.

Steve

I just had a sticky left caliper on my 1987 300D. When I got it apart to inspect, the piston had rust blisters. And they were small too - it doesn't take much to lock the piston.

So, I found that the prices here on FastLane for new Lucas calipers were reasonable, so I got a pair.

I did both because I decided they had both endured the same maintenance, and had been exposed to the same old brake fluid. Now I have a nice new pair of front calipers, new premium brake fluid, and no worries.

:)

Ken300D