The common Buna and Neoprene is starting to show that Diesel containing 'reclaim' containing Oleic Acid begins to soften and swell in long term contact.

In those industries doing/using 'reclaim', the common practice is towards to use viton or fluropolymer, etc. gaskets, seals and hose, etc. When the 'reclaim' is below 5% concentration there is little to no untowards effects typically found.