Jvette73

My front calipers are stainless steel sleeved but I think my rears are not. However, the rear bores are in very good shape with no galling or pitting at all. So could I still benifit from the O-ring kit for the rear calipers even though they are not SS sleeved? I know SS would have better life and a better seal, but I should still be able to benifit from the O-ring conversion shouldnt I? Or would it be a "total" waste of time and money? The bores on my rear calipers are as good as new.

hunt4cleanair

Stock calipers are replaced to avoid pitting...once the originals have already pitted. You'll benefit from a tight seal by going with O rings but maintainence depends on type of brake fluid you are using and the frequency you change brake fluid.

Dot 3 has an affinity for moisture and if changed annually, will avoid the pitting associated with standard sleeves and use of Dot 3. It's the moisture buildup over time in a sitting car that causes the pitting.

Silicone brake fluid has an affinity for air and is friendly toward cars that sit. So it comes down to how often you use the car. If brake fluid heats up sufficiently to evaporate accumulated moisture in your brake fluid or if you change regularly...then no need to change the rears. Just upgrade to the O ring pistons to gain their benefit.

Corvette was plagued with this problem in the late sixties when they learned Corvette owners were allowing their cars to sit...for long periods of time. They were engineereed and designed to be driven. We (owners) tossed a new one at them they had not thought of...long-term storage !

Jvette73

Thanks so much for the response. You gave a very good explaination. actually the car will only sit for the most, 2 months during the snowy months of winter. The rest of the year its driven quite frequently so long as its not raining. Right now I have a stripped inner bleeder threads on the right rear. Today Im going to remove and dis-assemble that caliper in an attempt to drill and tap for a larger bleeder screw. If succesfull ill bleed em all out and see how it goes before deciding on the O-ring kit. One more question. If a well sealed brake system can keep the fluid from leaking out, how does water get in?

hunt4cleanair

We may have to look to someone who can offer a technical discussion on this point but Dot 3 is hydroscopic and I believe, as the fluid heats and cools...it condenses and therefore the byproduct is moisture. The moisture "sticks" to the dot 3 molecules. That's the best I can do...I'm sure others will jump in.