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Vibration-Am I missing something?
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Robert & Dick:
Had a lot of issues happening all in a few months time when I had the universal joint replaced at Prevost. Digging through my foggy memory cells, I thing the vibration may have been more pronounced after the universal joint service. How do I check and resolve this if it is an issue.
Chuck
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don’t take my reclections to bank. I just remember the locations of u-joints not being correct. Seems to me the splined shaft could be put in two differant ways. I choose the wrong. I mark things now when I take apart. Was trying to point out you have been solving a problem in one direction of thought. Maybe think back what else could be.
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Robert:
I agree with you, looking back at other things is a good idea. Only problem with the looking back is I can’t even remember what I had for diner yesterday LOL.
Chuck
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Look in the online manual for your coach, use the VIN#. I’d like to think that will enlighten you.
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Dick:
Looked at the hard copy owners manual I have in the coach and the online manual. Both have a wealth of know age, but found nothing specific to drive shaft installation/balancing.
Any thoughts as to how to confirm proper re installation of drive shaft.
Chuck
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A drive shaft must be marked prior to removal so when re-installed, it is bolted in the exact same position from which it was removed. If removed and NOT re-installed exactly as removed, it can cause CONSTANT / NOT INTERMITTENT vibration. I.e., if it vibrates at 65MPH, it will always vibrate at 65MPH. Another cause of drive shaft vibration is if a balancing weight falls off. However, this would not be common since they are welded to the drive shaft.
Here is a company in your area that balances drive shafts…
https://www.parkerstire.com/Auto-Repair2/cat/axle-cv-joint-driveshaft-repair/svc/driveshaft-balance
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Chuck: who did the U-Joint work? Prevost? Call the shop and talk to the shop manager. Let us know what he or she says.
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Vibration was getting worse. Went back to tire shop and had them re-balance all the 365s starting with the drivers tag (that was the tire that required the most weight during the original balancing). Turns out all 4 newly mounted tires (both steers & both tags) had moved on the rim and were out of balance. I had carefully driven about 300 mile (not braking hard) to not have this issue, but it happened anyway. All weights were taken off the tires and they were spun up on the tire balancing machine here is the results. First # is amount of weight used at first mounting and balancing second # is the weight required when spun up the second time on the machine.
Drivers steer 8oz first time – 4oz second time
Pass steer 4oz first time – 14oz second time – rotate tire 90 deg then it took 8oz
Drivers tag 12 oz first time – 6oz second time
Pass tag 10oz first time – 6oz second time
Marked all 4 tires at valve stem. Have driven another 300 careful miles and all 4 tires have moved another 1/4″ on the rims. My current plan is to drive a total of 1000 miles on the tires (the vibration is not to bad now) then have them rebalanced or maybe have Centramatics installed.
As an additional Note:
Tim T posted a link on this thread on 1/2/2021 to a instruction sheet from Prevost for “REDUCTION OF HIGH SPEED VIBRATIONS ON VEHICLES EQUIPPED WITH DETROIT DIESEL SERIES 60 ENGINE” Go back and look at it.
Per the instruction sheet I measured the distance between the rear (of the bus) motor mount base and the rubber mount. I have about 1/8″ on the drivers side and about 1/4″ on the passengers side. I have ordered the shim kit from Prevost, $670 and will up date when received and installed.
We have 3 Featherlite’s H3s years 2000 – 2003 in our neighborhood. We have driven each others coaches and guess what, mine has the most vibration. One of the other coaches has a little vibration at about the same speeds, his also has the gap in the rear motor mounts (but less than mine). The 3rd coach has no vibration and no gap at the mounts. I do believe we have something here.
The neighbor with the light vibration has also ordered the shim kit. Will report back when the shims are installed
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Chuck, you are verifying why I state wheel weights are only temporary and that tires move relative to the wheel.
If Centramatics were not on my coach when I bought it, I would have been using Equal or its equivalent. I used Equal from about 1995 to 2012 and the only thing I had to do was after checking tire pressures give the valve a strong shot of air to insure nothing had gotten under the seat of the schrader valve. I also only used the schrader valves with the fiter screen.
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In the beginning of Prevost offering IFS, once established the motorhome shells had it as standard equipment. Seated Coaches on the other hand, yes, as stated above could choose IFS as an option.
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Tim T:
I need your address to send you a trophy (LOL), Your post on 1/2/2021 with the link to Prevost instruction sheet ref Reduction of high speed vibrations on vehicles equipped with Detroit diesel series 60 engine.
I purchased the shim kit and installed per instructions. Although not a complete success, there has been about a 70% REDUCTION in the vibration. The engine does not have a bump when shifted from Neutral to Forward or Neutral to Reverse anymore, and engine has less of a shutter when shutting down too.
Prevost does have the part numbers still in their system but does not stock them any longer. Prevost had to have their vendor make a set and send to me, about 2 week lead time and a cost of $65. Installation was fairly simple, passengers side took 5/16th of shims to correct, drivers side took 3/16 of shims.
Since last post I have also put all new shocks on (Koni adjustable on the front), had all Norgen valves replaced (with compression fittings added too) and ride height and drive shaft checked too (both were OK).
Thinking final minimal vibration left can be dealt with by installing Centramatic’s.
Chuck
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How do we get some pictures if there was anything sent to you with the parts, thanks.
Good to read success on the hunt for your problem.
You will be happy with the Centramatics installed. Centramatics come shipped on soft ride setting.
In my case that was exactly how they were installed right out of the box.
AL
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Al:
Go back in this chain of post to Tim’s 1/2/2021 link he provided. Prevost Instructions and pictures will explain.
Chuck
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Chuck;thanks for comeback! I had new mounts about 10,000 mile ago. The drive shaft was my error several years ago. you can’t even tell my engine is running in bus. I don’t have any vibration. 329,000 miles. Watching for any signs at this point. hopeing 500,000 before bull gear then who knows. Keep her oiled any maintance she will treat you good.
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Glad it worked out for you!
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