So this posses a question that's been runnin' round my head for a while. I just installed new U joints because of a vibration that started only at speed, around 4thousand rpm and up. It too would happen with the clutch in and seems to be drive line related. As usual for U joints, I jack the car up from the center pumpkin and use jack stands on the axel housing. I notice after removing the U joint U bolts, that the drive shaft only goes a little ways into the transmission in order to swing the shaft clear of the yoke. I figure if I go over a bump in the road, the suspension will unload a bit and move the shaft/front yoke into the transmission. I used to have a powerglide in it and it was real smooth. So, what is the optimal place for the spline/yoke depth into the trans? Is there a signifficant difference between powerglide and M21? Could this be your problem? ie: drive shaft length BTW the Precision brand of U joints are way beefier than the ones I replaced. -ChuckK
According to Craig A. Ellis: > Thanks, Steve. When I first put the shaft on and found no joy, we complained > to the owner of CCI and he came up and checked it out. Said the pinion > flange was shot, ordered new, installed, no joy. We're pulling the shaft > today to do as you recommend... > > U-joints are brand new, BTW. > -----Original Message----- > Craig, > Did you say that driveline was balanced? I'd take it down to > another shop and have them test it. > > Also might try new U joints on both ends. I'd be looking hard at them > u-joints first ..and replace them just for "grits and shins" ( a southern > dish isn't it?) because they are cheap. If the U-joints don't get it, maybe > a balance weight came off the driveline ......if it was ever balanced. A > good driveline shop will tell you quickly. > > Steve > > Brand new bearings all through the rear axle assembly. No play in anything > that I can find anywhere. I don't think it's the front end because it just > does not feel like front end stuff. I've had six different guys ride & drive > the car and all conclude the same - driveline. I keep racking my brain > trying to think if there is something I've missed but every single part is > new. It's really bugging me. > > With the way the axle is positioned by the control arms, it's just about > impossible to get the pinion and transmission flange angles wrong. Besides, > the angle changes constantly so I'm putting that pretty low on the list. I'm > down to crush sleeve, control arm bushings, and maybe drum balance but none > of those really seem likely culprits. I sure am open to ideas, tho'. > > E > > > I have what feels like a driveline vibration that comes in about 45 miles > per hour and increases in intensity until about 65 MPH when you're actually > going so fast that the frequency becomes so rapid it seems to go away. I > don't think it actually goes away, just feels not-so-bad, if you know what I > mean. > It is not engine RPM related - it occurs in second, third or fourth at the > same speed and continues if you disengage the clutch and put the trans in > neutral. So, it is not engine balance related. > I have new Moser axles, US Gear ring & pinion (3.42), new posi clutch pack, > new pinion flange, new driveshaft and it has done the exact same thing with > two completely different sets of tires and wheels. Also, it is not in the > front end. > I'm really at a loss here - the Detroit Dreamcruise is spooling up to max > output right now and I can't motor down the highway. (By the way, the > cruising is so heavy every night this week that the police will shut > Woodward Avenue down on some nights. On Saturday, you're talking a million > spectators minimum. It is said to be the largest motorsports event in the > world, bar none, and it's all muscle cars, hotrods, and other gearhead > doodah.) > If anyone has any ideas, I am sure enough ready to listen. > Craig E. > -- --------------------------------------------------------------------------- [EMAIL PROTECTED] [EMAIL PROTECTED] `65 Chevelle Malibu 327 4 spd --------------------------------------------------------------------------- ----------------------------------------------------- To Unsubscribe please visit www.chevelles.net/list.html To start a new topic, send mail to: [EMAIL PROTECTED]
