When I was coming home from the Davis Mountain State Park last week I noticed a noise/vibration in the back of the MH. I just now checked on the driveshaft and u-joints. Thank you Jesus that I got home, the u-joint at the tranny is gone and coming apart. I have greased them in the past, must have been to long ago.
Ya, they both look DRY.
I don't mind seeing grease coming out and even a little "slung" onto the bottom of the coach above them.
Remember, when greasing, either zirk works-- they go to the same center reservoir. And grease until clean grease comes out all 4 cups. Wipe off access.
I grease mine twice a year with a moly grease. Grease is cheaper then repairs.
Brett is technically correct, both zerks go to a centre reservoir. But I have spent many years in the trucking industry and my experience has taught me to grease both grease nipples. It only takes a minute to grease the other grease nipple and if you do you will find you do not have a u joint failure. The second thing is if you are stuck , grease the u joints before you really apply big power and you will find the u joint will survive the strain. We run 650 HP in Canada and haul 62,000 kg loads. Yes the math is correct. Rarely does a trucker loose a u joint.
Anyway that has been my experience,
Safe Travels
Dave
Really dry. You really can't grease them too often and grease should come out all cups. As Brett says, nothing wrong with seeing grease thrown on the bottom of the coach. I grease all Zerks a.k.a Zirks on U joints. A good manual gun will develop more pressure than an air grease gun.
Pierce