Driveline and ride height

[Gary and Judy]

I have a 2001 Alpine FDDS. Last month I had to replace the driveline universal joint. The u-joint bearing was nothing but powder on one end. Yesterday I stopped at Pacific Power in Ridgfield WA to have them assess the steering. They checked things out and found the rear end ride height was low by 3/4".

These coaches have such close coupled drive lines that that having the ride height off by that much could easily cause a u-joint failure.

The running gear was fine, but I will be replacing shocks. That thread opens a whole new can of worms.

Gary

[wb7auk]

Gary,
Make sure they measured it at the proper place as most times they do not.

[Gary and Judy]

Originally Posted by wb7auk

Gary,
Make sure they measured it at the proper place as most times they do not.

Yes that is a problem. They did not have the proper manuals. Thankfully we have the ACA Tech Library. I was able to download the proper manuals and specifications.

My praises and thanks to those with the foresight to gather these important documents.

Gary (KB7CE)

[wb7auk]

Originally Posted by Gary and Judy

Yes that is a problem. They did not have the proper manuals. Thankfully we have the ACA Tech Library. I was able to download the proper manuals and specifications.

My praises and thanks to those with the foresight to gather these important documents.

Gary (KB7CE)

Yes having been there and ending up instructing the shop as to where and what the measurements have to be after being told they checked it and charged me several hundred dollars and could not rid it of a vibration.
When they say max of plus or minus 1/4 inch that is what they mean.

[Skip426]

Originally Posted by Gary and Judy

The u-joint bearing was nothing but powder on one end.
These coaches have such close coupled drive lines that that having the ride height off by that much could easily cause a u-joint failure.
Gary

If the U joint needle bearings in only one cap were gone , then I would suspect a bad cap seal , poor grease distribution in the cross, or lack of proper maintenance. If your lubing the joint yourself , you need to keep putting grease in, till you see it being forced past the seal on every cap, then examine for rust in the grease as you wipe off the excess.
Excess drive shaft angle , will give shudder on start out , vibration at speed, and in extreme cases snap the cross of the joint, if the warning signs are ignored.

[Algoma]

Those U-joints were the subject of several threads in the past, failure was mainly due to lubrication issues. I don't think ride height has anything to do with it.

[wb7auk]

Originally Posted by Algoma

Those U-joints were the subject of several threads in the past, failure was mainly due to lubrication issues. I don't think ride height has anything to do with it.

You are correct in most cases failure is caused by lack of grease however
if the ride height is not correct the life of the u-joint is reduced greatly.
As well as the output bearing of the transmission and outer pinion
bearing.

[Renipladlo]

FWIW - The U-Joints are to be lubricated every 3000 miles, this would include the driveline Grease Zerts at the same time. I figure twice a year, usually before I head out in the fall and once I return home in the spring. That is way under the mileage limits, but it reminds me to do that service. Cummins did it August 2013, and I did it in April of this year. I do the oil and filter on Genset at the same time I do the ISL-400, and hit the genslide screw drive and roller bearings then.

[Stretch]

I think,you should follow the suggestions of these knowledgeable folks. We had a 2000 and an 03 Alpine from new. We had friends with alpines that lost front joints while going down the road. Not good. We learned from this and lubed the joints often. I always suspected angularity was too great. The chassis designer, Gary jones always denied it. Our current coach an 05 hr navigator has no such problems, although I keep the u joints well lubed anyway