Undercoating may block drain holes encouraging rust
I didn't want to find out. All has been working very well. Messing with the driveshaft can cause unwanted vibration.
Probably can't hurt to spray the driveshaft with fluid flim if that bad. It'll probably wash off anyways if you have weather like we do.i am at a loss & what to do currently on my '97 driveshaft, all the coating is off so its gotten a bit roachy
no clue if the joints still hold grease, it flung grease all over the muffler the last go at it
awhile back i priced new spicer shafts for a cost of 700$-900$ just for parts! that may or may not have included a new center carrier bearing
went thru this whole ordeal of diagnosing driveshaft when i had a nasty intermittent banging rattle rattle going on somewhere... it was not the driveshaft
Its likely similar to fluid flim and others if their only good for that amount of time before they wash off and need reapplying. Been there, tired of rust inhibitors that don't last. Right now i'm sold on cosmoline. Been over 2 years and still holding up like it was just done. Thats what i call a win.