I have had this annoying driveline vibration for some time. Its really noticeable at speeds over 60. I just checked my angles and the trans is up 4 degrees and the rear end in down 2 degrees. Is this enough to cause a noticeable vibration? The driveshaft was built and balanced by a my local machine shop.
To start, they should both point the same way. front higher than rear. If you have that and 4* on trans with 2* on pinion, you probably have a balance issue, worn u-joint, worn pinion bearing, something like that.
First, look at all the angle explanations by one pont of view from the driver's side of the vehicle. Imagine a line that goes through the center of the crank/trans and pinion. The ultimate goal is to have those lines to be parallel as the vehicle sits at ride height. Beyond that, please research my lessons using angle as a search word. I won't say I'm anything other than having just a little experience. I can help if needed and pm request sent, don't mean to be short, sorry.
Go to markwilliams.com and do some reading. Good info there. Aw ****, you beat me Patrick! Now I'm going to do the search, too!
http://www.vibratesoftware.com/html_help/html/Diagnosis/Propshaft/Propshaft_Angles.htm#Measure everything you need to know is here.
If you want to confuse yourself without having a good foundation and know what to enter------------- www2.danaexpert.com Look for the torsional anylisis program. Trust me, it works on easier stuff than this. Fun to me, Crown too.
What he said. The angle is probably the problem or a factor in it but first I would check wheelbase from side-to-side as well as wheels square corner to corner. I once had that vibration and that was the sollution.
Thank's guy's. I understand the theory with the centerlines being parallel, and the 3 degrees up and down. I really just wanted an opinion if mine being off no more than it is would cause my vibration. Just saw that my trans mount is toast from the trans leaking. My trans will be more like 5 degrees at least when I fix that.
Four degrees up and two degrees down results in a combined driveline angle of only two degrees, which theoretically should be about perfect. That is probably not the source of your vibration.
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