I have a 1988 s10 with a 455 Buick engine. I first made a driveshaft myself. I found I had a vibration at certain speeds. I had the driveshaft checked and balanced. Still had vibration. Had new driveshaft made. Still vibrates. It seems like a harmonic type vibration and it seems to get better when you put trans in neutral like mabe coming from engine. Anybody had this kind of problem? I have checked all u joint angles and currently am running about one degree down on rear. I've tried it several ways. any info would be appreciated. Bernie Steffen
Not sure how you measured "one degree down on rear". Correct measurement is taken from the trans output (ex: -4) and another from the pinion yoke (ex: +2) for a total of -2. If you have -4 at trans and -1 at pinion you have a total of -5, not good.
Out Angle Pinion Trans Wrong That sounds like the problem to me also. and check all your mounts also tranny and motor. Jim
Grab an S10 Service Manual There will be a section "OC" titled "Vibration Diagnosis". It will have flow charts to walk you through if it is an engine speed related vibration or a vehicle speed disturbance, show you the correct way to measure U joint working angles and how to balance a driveshaft using hose clamps. Good luck - by the way, it sounds like U joint angles to me, too. K
You never stated what trans you have in the truck. If it is not a shortshaft TH350 or TH400, your trans is wrong. A long tailshaft trans will affect pinion angle.
Driveline vibrations What I meant by one down was one degree further down than the trans was up. That means when you apply power the pinion tends to raise and the driveline angle gets better. I think I know how it"s supposed to be but sometimes I have trouble explaining it. The trans is a turbo 400. I didn"t know they made a long and short shaft. How do I tell? Thanks for the info and anwers. Bernie Steffen
The TH400 has 3 tailshaft lengths. One is 4" for GM A-bodies. The other is 9 and 13 for full size 2 and 4dr models. For a pinion angle article, see the article below. http://www.buickperformance.com/Pinion.htm