IRC's are generally cheaper and almost as good overall, and probably better in mud.
They DO have to be run at a slightly higher pressure, if you run 4psi at the rear try 5.
New shocks will also make a difference, so if they are very old start saving.
I would suggest that running the dial gauge on the inside of the rim would be more relevant to whether this is the source of the leak. The inside may have been buffed to match. Still not very good however.
Apparently the reason you cant use a pencil is graphite / broken lead + intricate electronic components/computers, added to no gravity, bad combination.
