Tried to replace front brake pads on my sisters 1984 380se today.
Passenger side completed, but had difficulty compressing the
caliper pistons back in, to make room for the new pads.

However, I could not budge the drivers side pistons. I DO NOT
have the special factory tool for this, just careful prying with
various implements.

What is the trick for this ? Or do I have to replace the caliper ?
If so, any special tools required for this, other than a torque
wrench ?

One trick is to open the bleeder screw before compressing the piston. In fact, some anal retentive mechanics prefer to open the bleeder screw before compressing the piston for reasons I don't fully remember. I believe it has something to do with keeping old fluid from being pushed back into part of the system.

Are you sure you don't have a C-clamp around? That's all I've ever needed to compress pistons back into the bore.

All that said, I don't get a warm feeling knowing that the driver's side caliper pistons are hard to push back compared with the passenger side. I'd be inclined to either rebuild the caliper or replace it. At least take it apart to see what condition it's in.

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95 E320 Cabriolet, 159K

Thanx for the reply, Kestas.
Yes, I did use a small c-clamp in my attempt.
Still would not budge.
I'll probably just replace it. NAPA has them for
about $90 each.

I had a frozen piston in a caliper on a "creampuff" SL I just bought. I replaced all 4 calipers on principle, because the brake fluid was like rusty milk (naturally, I completely flushed it and replaced it). From what I've heard, if one caliper goes bad, they probably all will soon - a big contribution being (in my case) the brake fluid neglect. I'd add that a C clamp is OK but a piece of wood or metal to push evenly is important. Don't cock the piston! If a little force won't budge it (assuming the pressure has been releived at the bleeders/master, it's got a real problem.

rmurray, try the FastLane link on top of this page. You may be able to save some money.

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95 E320 Cabriolet, 159K

www.********.com for calipers.

Kestas, thanx for the tip on FastLane, I'm new to this board.
Awesome online catalog, pictures of most parts , too.

Yal, I'll check out ********, also.

I bought rebuilt calipers fromn Autozone.com for around $40-$45 I believe. There is a core charge of course, but that isn't a big deal as long as you return your old ones. The core is also $40-45. They come looking brand new. Also, when you do this, replace the rubber hose sections. It is pretty standard to do the rubber pieces when you do the calipers. Also, make it a point to do both sides. Use plenty of your favorite spray lubricant, (PB blaster is a good one), on the old lines and be careful not to twist the steel line or it will break, rather easily I might add.
Thanks
David

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2000 Honda Accord V6 137k miles

1972 300SEL 4.5 98k miles

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The only tools that you MIGHT consider to be special are the line wrenches. You MUST have them or you will just strip the steel lines, ask me how I know? I ended up using vice-grips on my mom's becasue her cousin had already tried an open-end wrench on them. It was too late to use our metric line wrenches. Sizes are 15 and 11mm I think? Those are the only "special" tools that I could think of.
Thanks
David

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2000 Honda Accord V6 137k miles

1972 300SEL 4.5 98k miles

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