front brake caliper piston diff

[Nacho-RT74]

whats the diff between bendix caliper piston 90018S and 90024S ? I can't find anything on specs.

this is my kind of calipers and I'm not sure of the diameter either.



it does look there are two diff diameters ? 2.75 and 2 19/32 ?

same question about the correct piston seal kit.

[hemi71x]

Maybe your looking up things incorrectly.
The caliper you have pictured is a single piston, Kelsey Hayes caliper, it's not a Bendix caliper.

[Nacho-RT74]

right, however everyone manufactures pistons for every piece in the market. AC DELCO for example sells/manufactures dist pick up coils for Mopars

[John_Kunkel]

The difference in the part numbers is the diameter, the 90018S is 3.11" (79MM) and the 90024S is 2.75".

The "S" means it's steel.

[Nacho-RT74]

Ok this is kinda weird... a friend of mine got the Raybestos DPS85016 for his 73, with same calipers that I have, which states on specs ( By Rockauto ) 2.752" diameter. He is already using them.

No one of the Bendix units you posted diameters, meets this diameter.

I just wanted to get use of the Wholesaler Closeout for the Bendix 90018S, which is half of the price, but it looks won't be posible ?

The best of all is the GREAT Rockauto customer service is not being helpfull really this time... I asked about this and the response was:

The 90018S is designed for rear brakes which are 11 x 2" or 11 x 2.5". If your vehicle does not have rear brakes with this thickness, then you want the other part number.

which is a quote of the specs, nothing more nothing less

my car is 11x2.5 at rear

[John_Kunkel]

The 90018 was used on '74-'78 C-bodies and numeous trucks.

The 90015, 90016 and 90024 are all 2.75"....don't know what makes them different.

Correction: 90024 is 2.60".

[Nacho-RT74]

maybe the lenght?

[Nacho-RT74]

yeap, John, confirmed...90018S is the diameter you told.

went with Dormans 7505S wich were $10 each free shipping in Amazon ( last ones BTW ). Get them from Rockauto was $10 more due diff shipping location of the rest of stuff I'm getting from them.

In fact ANY OTHER PISTON from Rockauto diff than the 90018S was to get that $ diff