I've had a pair of Marzocchi Mx Pro's with ETA + TAS from new since 2006. They've never had a proper service as well, they've never felt like they've really needed it although recently i've been thinking about an oil change.
On a ride last week i felt my forks were rebounding way too fast so went to the bottom of the right leg where the adjuster is to slow them down. When i tried to turn it, it was extremely stiff then when i finally got it to move it just sprung back to where it was before. So atm i'm stuck with a fork that is rebounding way too fast for my liking.
Next week/soonish when the new summer 456's are released i will hopefully be buying one, i've been thinking of changing to some Pike's when i get it as my style of riding has been changing and getting alot more aggressive recently, stuff my Maxlight doesn't really like handling, so my question is do i:
A) Flog the forks on eBay with a dodgy rebound ajuster, obviously making the buyer aware of this fault, and buy a pair of Pike's to compliment the new 456.
B) Send to TF Tuned at a minimum cost of £70 + postage. Bearing in mind that £70 could increase if its a serious problem.
C) Bodge it and service the forks myself hoping i can get them back together.
Dont force it. If they are like my '03 MX Pro's they have a design flaw where the rebound adjuster rod (metal, internal) adjusts a nylon valve. The metal rod has rounded off the socket in my nylon valve and now I can only adjust them by disassembly.
Go for A) or if you want to keep them C).
Most forks are easy, if messy, to disassemble, and only slightly harder to re-assemble. Just make sure everything that comes out goes back in though.