That's right ... another driveline vibration

[HBarlow]

An experienced full service driveline shop can true a driveshaft to take out the slight run out present in some OEM shafts.

I watched it done once when I had a bad deceleration vibration on a '57 Chevy. The shop owner spun the shaft in a lathe and measured run out then used an acetylene torch to heat then quick cool an area to shrink it. It took several "tweaks" but he made it smooth as glass.

 

[sag2]

So how does one measure run out? Sorry, this is all new to me ... .

You use a dial indicator and spin the shaft by hand to measure if the shaft is spinning true, or off center. If not true, unbolt it from the rear flange and rotate it 180 degrees and check again. It should be better/worse/same. Ends must be less than . 008, center less than . 015.

 

[steved]

I had the vibes (search 70mph vibrations), this is an old topic. Some trucks had this from factory, and there is not single absolute cure.

I replaced all the ujoints... didn't help. I replaced the front driveshaft (removing the driveshaft caused it to stop)... didn't help. Had the rear driveshaft balanced (it took a lot of weight), and while it was smoother; the underlying vibration was still there.

I finally purchased a Free-Spin kit from dynatrac... vibrations gone.

I have heard that it is resonant/compound vibrations, and curing one of the vibrating components will cure the vibrations.

I have read where a Dodge dealer "realigned" the drivetrain in the chassis (as in realligned the engine/transmission in the mounts) with some sucess... they were rumored to have bought trucks with the issue from other dealers, fixed and then resold them.

I have also noticed that some of those with the vibrations have had catastrophic failure of the tcase... I have read of at least two instances of this. This isn't saying the vibrations mean a failing tcase, or that they are even related... but both instances the owners reported having the vibrations prior to failure.

I have always assumed it was a bad machined part in the tcase, as it is a highspeed driveline vibration and seems connected to the components forward of the front tcase output. At least in my case. And since pulling the front shaft stopped only the front output from rotating (differential still turning), that's where I assumed the problem was located. However, I have also read where the dealers have replaced all the driveline components (transmission, transfercase, driveshafts, front/rear differentials) and never solved the problem.

There are a lot of threads about these vibrations on this forum...

 

[Tejasdge]

Does anyone have a suggestion to get rid of the reverse hop/shudder? I have replaced the transmission mount, which helped for a while, and the u-joints, which didn't. When in reverse backing a trailer or up a hill, it starts immediately in 2Hi and 4 Hi, but does not do it in 2 Lo. Power braking in 2Hi and 4Hi, I feel it starting when barely moving. Any idea's?

 

[Texas Trucks]

I am going throught the same vibration problems with my Mega Cab 4x4. I took the front drive shaft to the drive shaft shop. It was not true at all. They heated it with a torch and cooled it to straighten then rebalanced it. Monday they will get to do the rear. I just figure if the quality of the shafts were so poor from the factory that I should not replace them with more factory parts. I have not reinstalled the front shaft yet. I will post when I have results.

 

[flyby night]

I had all of the fancy sealed u-joints in my rear driveshaft start squeaking on me at low speeds, and vibrating at higher speeds. (at 40k miles) So I replaced all of them with Rockwell Meritor greasable u-joints. (I have never had such a hard time getting u-joints out. I almost torched them at the crosses. )Then I still had a vibration at mid to high speeds. I thought the driveline was out of balance so I took it in to get it spun balanced. Apparently it was out of true at all of the welds. After the driveline shop re-welded and match balanced the rear driveshaft assembly, my vibration went away.



Until I got to about 62k miles on the truck, then I got a vibration that sounded more like a grinding. It was my left front axle u-joint. I made a puller to pull the front bearing/hub assembly, pulled the thing apart, and replaced the u-joints. Once again they were difficult to get them out. After replacing them though, my truck is smooth again. I also made up a grease hose using a rubber blow gun tip and pushed a little high quality grease in each of the front bearings, as many others on this site have done.

 

[Trophy Truck]

more vibration input and question

I have a 06' quad cab, short bed auto 4x4 (75K miles) and I have been noticing a vibration (shutter) when starting an uphill pull when loaded or unloaded. When I reach the top and start heading downhill the vibration is somewhat gone. I just went on a 3000 mile trip and noticed this vibration... In my mind this could be anything from engine mounts, trans mounts, transmission, slip yoke, pinion play, driveline problems like mentioned above. Any thoughts?

 

[MoparBob]

Any updates available?

 

[COwings]

Had the same problem on my 05;, did a visual inspection, saw missing driveshaft balance weights. Talked to the dealer he said bring it in, still under warranty. Thought I would just wait while they rebalanced. Service tech said the had to put a new Driveshaft in because they aren't qualified to do a simple balance job. GEE I wonder why these trucks are getting so expensive. So a forty dollar balance job anywhere else turned into a new driveshaft so they could get my hundred dollar deductible