When I had SRD rebuild my Penskes 3 shocks had almost no fluid left in them! That was 4 years of track & road use. SRD will be converting my Penskes from o-ring to seals at the next rebuild in 1 year. I recommend a 1-2 year minimum rebuild on the Penskes. Or get Ohlins or Motons since they use seals.
Ed
PS Shadowman R&R shocks, SRD rebuild!
Ed
I have some quad-ring seals. That fit in the Penske.
Send me a note- and I will drop them in the mail. If you would like to try them?
I would not be so sure those other Racing Shock Brands do not also use An O-ring to seal the shaft.
And I would take a first-hand look before buying (Don’t trust just any salesman)
I test and build more than a few shocks.
Performance shock guys are targeting low “shaft seal drag” designs
As a minor compromise in this area has effect on overall damper tuning range.
I have a group of shaft bearing seals on hand from Penske, Ohlins, Bilstein. And Fox.
And they all have a well-designed O-ring seal.
Penske is the only one that is Viton material .
The way I look at it. You should change the shock oil. When it becomes worn.
And I have never seen a Penske shock seal leaking nice clean, fresh oil.
When I get them they were used hard. And covered in tire rubber. Oils past due for a change.