Senior Member
"OK, Here is the answer to the bobble/bounce.
I had the ride height checked, left side 1 1/4" lower than the right.
Corrected.
The rear engine mounts were loose. Corrected
The tranny end of the drive shaft 'U' joint was worn out."
Jon,
Eat your heart out! Motor mounts..won't make it shake, ride height, no factor, but U -Joints... Bingo
Glad you got it fixed Larry, hope Desert West (if you went there) did well by you!
John
You know how long you have to go without greasing or inspecting a U-joint to get it to the point that it wears out I do.
20 or 30 thousand miles. What else or what next that would be my question.
Senior Member
Yah, and be checking for leaks at the transmission output shaft.
JIM
Senior Member
Joe and Jim I guess you are correct, but my immediate question is why the 'Honyak' that lubed the bus 2000 miles ago didn't find the sloppy 'u' joint. When inspected,[torn apart after removal] there was plenty of grease in the 'u' joint.
John, I didn't go to Desert West, I couldn't get them to call me back on a wheel I needed, so I ,in a pissy mood, elected to go to All Aborad America's shop in Mesa. Great group of guys, Leo the service mgr. is a good guy as well, got me in and on the road in short order.
They run a fleet of 40 or so buses plus service several motorhome & entertainer buses. I would recommend them highly.
He was greasing it with his eyes closed.
Coveralls and a grease gun. Best fifty bucks you will ever spend. Do that yourself. I find something new, wrong, almost every time I grease
Larry what Jim was eluding to in his last post was a u-joint that far gone and out of balance puts a great amount of abnormal stress on that trans seal and pinion seal the 2 yokes they ride on. They could have been damaged as a result.
In defence of the previous owner that u-joint may have been either defective or installed incorrectly.
Last edited by Joe Cannarozzi; 03-13-2009 at 03:21 PM.
Senior Member
I don't think the guy 2000 miles ago would have known unless he was looking.
I haven't had a U-joint failure on the bus but over the years with Corvettes and rear independent suspension I got to see and replace many defective ones. The first sign is that dry reddish powder. It is usually only at one cup. Our buses call for lubrication every 6000 miles or so. How many coaches only get lubed when the oil is changed, and how many oil change intervals are stretched to 20,000 miles? Grease is cheap.
If the U-joint has a grease fitting (factory originals on the Corvette did not) it is because the grease passage to the bearing cup was blocked that a failure occurs prematurely on joints regularly greased. Our buses have two grease fittings 180 degrees opposed. I give each a shot and make sure I see evidence of grease at each cup. So far, so good.
Senior Member
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.
Sounds like you may still have a drive shaft issue. The yoke could be wore out, it happens, that possibly may be the cause of the joint failure. It could be loose pinion or outputshaft nuts, the shaft may be bent from a foreign object, a balance weight may have flown off, the slip spline may be bad. You may have damaged other things as Jim said. A bad seal will not make you wobble but the bearings in the trans tail shaft and pinion bearings in the rear-end could have been hurt as well as the other u-joint could have been hurt from that first failure.
I would concentrate there.
Could be the new joint getting destroyed again already . It may be when you thought you found the problem you may have just fixed the resulting damage there of.
To add to Jons comments when you are greasing that you should make sure that you see new grease at every cup, it should appear at all of them at close to the same time. If you see one of them doesn't bleed grease till way late that is the beginning of the end. Grab the larger diameter end of the shaft (in the middle), at the spline, and jiggle it to check for excessive slop, should be minimal. Grab each yoke one at a time and do the same there should be almost no slop there. Check slop two ways there up and down (bearing) AND clockwise/ counterclockwise (u-joint).
Last edited by Joe Cannarozzi; 03-13-2009 at 08:28 PM.
Senior Member
Larry, look into changing the universal joint at the other end of the drive shaft.
Maybe you did, if not you should have.
Have the bearing and seal at the output shaft of the transmission checked. The bad universal that you replaces probably damaged it. IMHO if you need that bearing I would only have an Allison repair facility do the work.
How many miles on your bus? I think many here want to know.
It is possible that the drive shaft is not running true (maybe never did when new) and/or is out of balance.
Balance Master Co., makes a split collar balancer for the drive shaft.
JIM
Senior Member
Larry,
Glad to hear that you got everything fixed. Remember the addage from flying, if it ain't broke, don't fix it!
I will score those peoples name, Desert West has been good however it is in the shi%@r part of Phoenix and you really do not want to be there after dark. Wayne Mullis made the offer several times, spend the night...No Thank You! Too many run by fruitings in that hood...............
Run the coach for a while before you do anything, IMHOP
Best,
John
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