Does anybody have a source for obtaining a pair of the newer style pistons for the M46 overdrive (part no. 6814454)? My shop (Swedish Engineering in Ann Arbor) is rebuilding the OD in my 242. They have the entire unit apart and have the newer style o-rings, seals, etc., but were unable to get the pistons. They also tried sourcing the older style o-rings for the current pistons, but were unsuccessful. The current option is ordering the pistons straight from Volvo, but it's unclear to them when we might get them, as according to the dealer, they have to come from Sweden. If I'd known it would come to this, I might as well as gotten an Alfa Romeo.

If I remember from really old posts, three-five years old, J pistons were upgraded in 1978. Then changed in 1984 700's and 1986 240's P type to a smaller O-ring with Teflon over which was then superceeded backwards to the wide groove J type afte 1978 since the Teflon was not filed installable. Something about needing high heat to stretch without damage.

Old style piston O-rings size 2-214. Parker compound N06474-70 or updated or other companies comprable.

Well, I was unable to get the newer pistons in a timely fashion, but with some help from ODGuru, I took a chance and ordered a set of older style O-rings from IPD. They fit. It turns out that I didn't need to replace the pistons after all, as they were not the teflon sealed ones.

Much thanks to the board and the archives. Next subject to tackle, old weatherstripping. Also, I got my first compliment ever for any car when I stopped at the hardware store today while driving the old girl.

I got one pair from ipd and another from RPR.