Hop or bounce in drive train?

"Well, Hate to tell you all this BUT_____ the bounce is back."

Sorry to hear that.

I'll just wait with interest, but as I said, I think I had the same problem, just not on the Prevost.

Quote:

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Originally Posted by LarryB

Well, Hate to tell you all this BUT_____ the bounce is back.

We were on the road this AM headed North and at higher speeds than I normally drive 67-72 mph the bounce is pronounced. At 60mph the bounce is very slight [gone at 62-64 range]. I had a chance to experiment with speeds and different road surfaces and this is the condition I have now. Strange that the problem is less and has move to a different speed range. Before you ask, the test drive was done in Phoenix traffic so I guess not a real test drive.

I plan to press on toward home avoiding the speed ranges were the problem occurs and attack it again once home.

It has been suggested to have the engine tuned and the tires trued, would either of these contribute to the problem.

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Oouch Larry,

Jon never exceeds 62 mph so you could go with his theory. I'm like a 75-80 mph person so that won't float. Head over to Desert West before you leave, ask for Wayne thence proceed to puke in his Wheaties...POG Member yada, yada, yada. His service manager is from Marathon, married some chick who refused to live in the Beaver state (I understand).

He will find it and fix it...no choices on this one if it has re-appeared.

John

I have been known on occasion to slightly exceed 62.5 MPH. So I feel fairly comfortable saying if Larry is still experiencing a vibration, he should note all of the specifics.

Was he coasting, accelerating or maintaining speed under power. Is the road a contributing factor There is a three mile section near my house where I get a vibration in every vehicle I own like a tire is out of round or balance. It has to be the road surface.

Replacing a U-joint is something that has to be done correctly. If it not exactly centered in the drive shaft or yoke it will create a vibration. The fact that something changed when the U-joint was replaced keeps leading me back there.

Joe is correct. The driveshaft can be out of balance, or there could be slop in the spline. Unless someone monkeyed with the tires as well as the u-joint concentrate on the driveshaft from transmission to differential.

Jon, as to specifics ; the problem happens while coasting, accelerating,or maintaining speed. Road condition, the smoother the road the more noticable the bounce.
The 'U' joint was replace by a qualified shop with qualified techs, but someone may have screwed up--sure, I doubt it. The new part may be defective as well.
No one "monkeyed" with the tires, I was with the bus the entire time. I didn't drop off the bus and go to diner.

John, Desert West is in my rearview mirrors. We are in Camp Verde north bound. As I said --if they can't return a phone call that will result in the sale of a new polished alum. wheel, I'm not going to give them my business. In today's economy, they better get their s--t together or we will be lamenting another RV store shutting the doors. Just my opinion.

Larry,

The fact only the U-joint was changed, and that changed the speed of the vibration event strongly suggest the issue is somewhere in that driveshaft. Balance, U-joint off center, something.

Jon, going on that assumption, driveshaft, if I avoid the speeds that the vibration is most pronounanced, in your opinion is it safe to drive another 1000 or so miles home?

Thanks

Larry at the nearest large town stop and look up a driveline shop and have them spin your driveline. Most big shops work on trucks and cars so they should knew how to handle your bus. A clearance from them should eliminate anything to do with your driveline or u-joints.
GregM

Greg, thanks, we will be in a few larger towns before we get home. I'll check it out.

Larry,
Sorry to hear DWC did not return your call promptly. I know the owner and the manager at DWC and it does not sound like them not to be in touch with you. If you ever call them again, ask to speak with Chris Weaver, manager.
I have been satisfied with the work they have done for me over the last two years.

Larry, I would drive it home and keep away from the speeds which create vibrations.

I know from testing on products we used to make in the factory that the right vibrations can disassemble anything. That is not an exageration, but a statement of fact. We built shipping skids for Cummins engine and they had to undergo severe testing because they were to be returnable and have a 20 year life while enduring all modes of transportation from ships to planes to railroad to truck.

During the testing process I watched the vibrations at one phase of the cycle unscrew the bolts in the engine which was secured to the skid.