Just about to pull the top end and replace pushrod tube seals. My tube of Wurth DP300, which Oak said was the same as Hylomar, is 10 years old. While it appears to be good, the shelf life (according to the internet) is only 60 months. It appears Wurth DP 300 is no longer available in the US. After some searching, found a US contact for Hylomar in, of all places, Center Point, Texas. I called and asked which Hylomar was the same as Wurth DP300 and he stated that Hylomar M is what they filled the Wurth DP300 tubes with. Of course I had ordered Hylomar Blue the previous day as it seemed more available. But Valco in Cincinnati sells the Hylomar M which is now on the way from Amazon.

There's lots of other choices for sealant to use. I guess I use Hylomar in a nod to nostalgia and Oak.