View Full Version : Regular vs stainless steel pistons for calipers

01-25-2010, 08:59 PM
Stainless still worth the upgrade? Looks like they are about 3x the cost....

01-25-2010, 10:07 PM
IMO, no. But then, I'm a DOT 5 fanatic (and still using factory original pistons). Might be worth the money if you're going to run DOT 3/4. While you're at it, use the stainless steel brake lines, slave cylinders, master cylinders, etc.

01-25-2010, 10:08 PM
I don't think so. How messed up are the pistons you pulled out? Is the seal groove area severely pitted?

01-25-2010, 10:47 PM
Two are in good shape, two have pitting. On the two with pitting it is pretty noticable, and my understanding is that any pitting reduces them to scrap. Yes/no?

I'd love to re-use them if I could.

01-25-2010, 11:13 PM
Is your life worth risking over the item in question? Your passenger's?
Certain questionable items can be used, others just can't. I had the same types of thoughts when restoring my TR6. If the part in question had to do with safety, it was replaced.

01-25-2010, 11:25 PM
If the pitting is noticeable, and on an area where the seal slides, I wouldn't try to reuse them. Not worth the chance of wearing the seals and/or contaminating the pads, IMO.

They're only $11.25 ea @ BPNW; less than the seals & pads you'll ruin by trying to skimp.

01-26-2010, 12:16 AM
I tried to get by with cleaning up the pistons on my long dormant 6 and ended up having to rebuild the calipers again with new pistons. I ended up buying all new pistons from BPNW. Stainless? How long do you plan to keep the car? How long did the original ones last? If the answer to the first question is longer than the 2nd, then by all means go with stainless throughout. We do live in the west where the humidity is low and water doesn't absorb into the fluid as readily as some parts of the country. I just don't see the need for stainless.

01-26-2010, 12:22 AM
Thanks guys.

01-26-2010, 08:50 AM
One thing that amazes me is how a lot of people don't regularly bleed their brakes. I do so annually and buy fresh brake fluid, never use old stuff. Do that and regular pistons should last a long time.

01-26-2010, 12:07 PM
Pits eat seals. With new pistons and units "kitted" you should be fine. As long as the dust boots are well sealed and fluid flushed annually the 'regular' pistons should outlast YOU. :wink:

Don Elliott
01-26-2010, 02:33 PM
I still have the original chromed pistons in my original calipers on my 1958 TR3A. I took them apart in 1990 during my restoration and found that some of the chrome had peeled or chipped off and there was a but of surface rust. This was with 80,250 miles from new using DOT 3 fluid.

In 1990 I polished the outside diameters of the pistons and re-installed the same parts with new seals and have used purple silicone fluid ever since. I have had no issues in 19 summers and 102,000 miles. I have changed a bit of the 1990 silicone fluid bit by bit over the years and never gave it a full fluid change. I last bled the brakes at VTR in Breckenridge Colorado in 2001 because two weeks at that altitude must have caused some air to expand in the system.

01-26-2010, 08:22 PM
I bought new stainles pistons last spring from John Farrell Brakes in New Bethpage, Long Island, N.Y. 1-631-454-7977, he charges approx. $25.00 a pair. My chrome ones were very pitted. I think the chrome plated ones were almost the same price. They fit and work perfectly and will never rust.

1957 Tr-3
driving restoration

01-27-2010, 08:48 AM
My 2 cents.....
If you run a brake fluid that retains a lot of water (like silicone) you want to run stainless. If you never change your brake fluid, you want to run stainless.
If you run a regular dot 3 or 4 and change it every one or two years you will never have a problem with the chrome.

01-27-2010, 09:02 AM
Thanks guys