Howdy all.  This car is really becoming a money pit!  Took a long ride last week before the rain came.  Yes, sorry to say 1" in Los Angeles is a major event calling for breaking news and storm tracking.  Anyway my brakes went to the floor again, before I was home.  I just parked her in the garage.  Today I backed her out to store the Christmas decorations in the attic of the garage, and lo and behold, a puddle of brake fluid around the right front tire.

So, if my hypothesis pans out and I need to rebuild or replace the caliper, what's the vote, lip-sealed or 0-ring?

Do both wheels need to have the same type?  Any other words of advice before I start?

Jim

It's a fact of life that they will all need it.  Easiest way is to bite the bullet and do them all at once and get it over with....they are all going to leak.  I skipped the master cylinder and sure enough they would not "pump up" until I replaced that too.  My car was 23 years old when they started to leak. They had been getting "mushy" and bleeding them only helped for a short time.

Most folks will say o-ring and they're probably correct but for some reason I stuck with the lip seal when I rebuilt my fronts (they had already been sleeved and the sleeves and pistons were in good shape) and have not had problems so far.  I think the lip seals have the most problems when the car sits for long periods of time.  So if you drive it frequently they may not be as big of  a problem.  

 The main advantage of the o-ringed type over the lip seal type is that the o-ring set-up will NOT suck air into the system, as the lip seal ones do. The in-out motion of the pistons as they ride on the rotors while driving creates a pump...which sucks air in past the seals. Eventually, you have to constantly bleed the brakes. With the o-ring seals, this doesn't happen.
In your case, whichever type of seals you decide, you should at the very least do both calipers at the same time, whether front or rear. Fixing a leak on one side can sometimes cause the other side to start leaking. It's a little known effect called "Murphy's Law".....