Driveline vibration?

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SGBARRACUDA

SGBARRACUDA

ROY
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Ok here is the story. I bought a real nice all original 1990 Ram 150 2wd club cab, 318, 4speed. Well I put a new set of Goodyear Wrangler tires on it and took it for my first drive and it had a bad driveline vibration between 35-60 and then it gets less obvious. I pulled the 2 piece drive shaft out and though the u-joints seemed OK I replaced the three joints. The carrier bearing felt smooth so i didn't replace it. The trans is a cast iron granny 4sd. I noticed the yoke on the trans was loose so i tightened the nut. The 9 1/4 3.21 sg rear felt a little rough when you turned the yoke so I tore it down and replaced all the bearings in it. When I drove it again it is some what better but still has the vibration? Any ideas?
 
I just had a new set of Goodyears put on it This past tuesday. But it doesn't feel like a tire. Seems like it is in the driveline. And also it had the same vibration with the old tires when I drove it to the tire shop that morning.
 
oldkimmer said:
...........is the hanger bearing loose in the rubber or rubber loose in the bracket........kim.....
Click to expand...

No the rubber was in good shape, not sloopy, bearing was smoth. I've been told that a bad worn pilot bearing in the back of the crank can cause this?
 
How did you inspect the U joints? You cannot just "wiggle them in place." You must remove the shaft, take each joint, and slowly move it in all directions, feeling for roughness (rust, no grease, broken pins)

Also examine the shaft Each U joint cap MUST be inline all up and down the shaft If the shaft is splined, etc, and can be rotated out of line, or has a rubber (inner/ outer shaft) absorber, it could have twisted rotationally. That is, you should be able to sight down one cap and the other end should be exactly lined up rotationally.

Things like driv yoke/ pinion nuts being loose is a bad sign. Some vibration caused those to work loose. You may have something bent, etc.
 
If you keep it in second gear does it vibrate ? first gear or third ?
if not I would think the drive shaft was never marked and put back together correctly and is out of balance, If I remember right these drive shafts are balanced and must be put back correctly.. when removing these drive shafts I had to mark them with a marker before removing them to replace U joints, or was this just a chevy thing
 
Ok I'll run down the list. The drive shaft is in phase with each other. The u-joints were all replaced by me 2 days ago. The vibration is related to speed and does it in 3rd or 4th. Original engine and came with a 318. Engine is smooth when reved up. Clutch action is smooth, no chattering. I marked the two shafts with white paint to put it back together the way it was, what I may try is to rotate the rear shaft 180 degrees and see if that helps. Since the joints I took out were not original, someone might have put it together 180 out,
 
I would do a quick check on the rear's pinion angle and compare it to the transmission's angle. They need to be nearly identical and opposite. For example if the transmission is pointing down rearward at a 3 degree angle, then the front of the pinion shaft at the diff should be pointing 2 to 3 degrees up. If not, then use angle shims under the spring perches.
 
35-60 sounds like a tire ... what type of weight did the tires require to balance ? do you feel it in steering wheel or seat of pants ? rotate tires ? wheel/wheels bent ? has ride height been altered?
Best way to balance tires is to Road Force balance .... MOST of higher end shops have this type of balancer ...
 
The truck had a set of Dry rot Michlins on it. I just put a new set of Goodyear Wranglers on it. It had the vibration with the old tires just as it does now. Idon't think it is a tire or wheel but tomorrow I'm going to rotate the rear shaft 180 and see if that helps, it may have been put back in wrong the last time the u-joints were replaced. Pinion angle looks good as I thought of that already. Truck is 100% original, not lifted. Even has the stock size tires on it. I runs so smooth until you hit 35-45 then you feel it in the seat and all through the truck, but not through the steering wheel. Hell I'll figure it out sooner or later. Thanks for all the tips Guys!
 
When I'm working on a vibration like that, I'll jack the truck up,put it on stands and try it.I'll have a friend run it at the speed it vibrates and I'll watch it.Remove tires and drums if need be,what ever it takes to narrow it down.Even rotate the drive shaft 180 and try it on the stands.All this eliminates road interference and tires.Hope this helps.
 
Start simple, Rotate the tires,....Seen goodyears cause this prob more than once,...

68gtxman may be onto somethin as well,...had prob with my Ram 1500,...had a lift kit in it when I bougt it,...could not keep a rear diff in it cause the angle was all jacked up...
 
Well here is an update, I took 68sedan aproach. Today I put it on the lift and started by removing the rear half of the driveshaft.I ran the truck in 4th gear and the vibration was still there. I then tried reving the motor with the clutch in and no vibration. So it is not in the motor balance. I them removed the front half of the shaft, ran it again and bingo, no vibration. So I took I the driveshaft to Central Driveshaft in Lakeland. He called and told me it was done about 2hrs later. What he told me was that the male spline shaft was not centered in the driveshaft, or it was crooked. Came back, bolted it in and now it is smooth as silk, Gravey Baby! Thanks guys for all your help. Case closed.
 
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