I'd agree. You should never have to crack a bleeder to push in a piston into the caliper. You most likely let some air into the system. If you resevoir was low, this might also let some air in.
I now use a set of welding vise grips. These ate the ones with the extra long arms. The one that I bought has a large flat swivel ends. I think they are called locking C-clamps. This gives a larger safe surface area for the force needed to press the piston back in. One tong will fit right into the piston, the other can go behind the caliper body. Press the handle together, readjust the threaded adjusting screw and do it over and over.
If the pistons were that hard to press back in, you may have a master cylinder problem. It is not letting the brake fluid back into the system and releiving pressure. You may have slight braking pressure applied to the pads at all times. It may not be noticable at this time, but it will cause your pads to wear much quicker. After driving at least 10-15 miles, put your hand on the outside of front wheels by the lug nuts and notice the temperature. Now do the the same for the rear wheels. If the fronts are noticably hotter, this may be your problem.
'05 E320 CDI - 86,000 miles
'86 300SDL - 360,000 miles
'85 300SD - 150,000 miles (sold)
'89 190D - 120,000 miles (sold)
'85 300SD - 317,000 miles (sold)
'98 ML320 - 270,000 miles (sold)
'75 300D - 170,000 miles (sold)
'83 Harley Davidson FLTC (Broken again) :-(
'61 Plymouth Valiant - 60k mikes
2004 Papillon (Oliver)
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