Vibration Problems....advice needed
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Joined: Jul 2006
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From: Atascocita Tx
Vibration Problems....advice needed So this weekend I changed out third members in my 9inch with new gears, locker and all.
Well before I changed out to this new third member I had allot of vibration issues as it was but could never pinpoint it down with the number of em that I had (because old third member was TOAST). Well now I changed out this third member and I am getting a vibration that seems to get higher with speed. At first it seemed like it was only in 4-6th gear but the more I drive it I'm pretty sure its from about 35mph+.
I wasn't sure if it was my driveshaft being too short so I took it back out today to check. Here's what I got.
My old driveshaft is this PST 3.5in aluminum driveshaft. It was too long so I had to use an old steel 3rd gen driveshaft I had,
had the unjoints changed out to convert it to a 1350 yoke. If you can't tell the spray painted orange one is the steel one.
Here is how much engagement I have. About 2.75inches
Here is the difference in fronts
Here is a possible culprit perhaps?
Looks like that weight may have come up a little at one side.
Well I put it back in there and still vibration. I checked pinion angle and set it accordingly and still vibration.
I'm starting to think it's actually my transmission that could be messed up. When I stuck the driveshaft
on the output shaft and started turning I could hear a bunch of clicking inside the trans. I tried shaking back and forth
but couldn't tell if it was play in the output shaft or if the driveshaft was just turning.
I'm kind of stumped, I'm going to try throwing in a different trans when dmy buddy is done with my spare.
I'm thinking maybe whoever it was that painted this driveshaft may have thrown off the balancing or it's the trans.
When I dump the clutch into 6th or 5th gear on the hwy (While not accelerating or high rpms) It feels like that trans kind of moves back and forth. Also when car starts to surge with the locker engaging on a turn or in first gear that it feels and sounds like that trans moves back and forth.
Should the driveshaft have been balanced when throwing on conversion U-joints?
Anybody have any input on this? Perhaps another view on what I'm thinking or something I have not thought about?
Thank's allot guys....sorry about the novel.
Well before I changed out to this new third member I had allot of vibration issues as it was but could never pinpoint it down with the number of em that I had (because old third member was TOAST). Well now I changed out this third member and I am getting a vibration that seems to get higher with speed. At first it seemed like it was only in 4-6th gear but the more I drive it I'm pretty sure its from about 35mph+.
I wasn't sure if it was my driveshaft being too short so I took it back out today to check. Here's what I got.
My old driveshaft is this PST 3.5in aluminum driveshaft. It was too long so I had to use an old steel 3rd gen driveshaft I had,
had the unjoints changed out to convert it to a 1350 yoke. If you can't tell the spray painted orange one is the steel one.
Here is how much engagement I have. About 2.75inches
Here is the difference in fronts
Here is a possible culprit perhaps?
Looks like that weight may have come up a little at one side.
Well I put it back in there and still vibration. I checked pinion angle and set it accordingly and still vibration.
I'm starting to think it's actually my transmission that could be messed up. When I stuck the driveshaft
on the output shaft and started turning I could hear a bunch of clicking inside the trans. I tried shaking back and forth
but couldn't tell if it was play in the output shaft or if the driveshaft was just turning.
I'm kind of stumped, I'm going to try throwing in a different trans when dmy buddy is done with my spare.
I'm thinking maybe whoever it was that painted this driveshaft may have thrown off the balancing or it's the trans.
When I dump the clutch into 6th or 5th gear on the hwy (While not accelerating or high rpms) It feels like that trans kind of moves back and forth. Also when car starts to surge with the locker engaging on a turn or in first gear that it feels and sounds like that trans moves back and forth.
Should the driveshaft have been balanced when throwing on conversion U-joints?
Anybody have any input on this? Perhaps another view on what I'm thinking or something I have not thought about?
Thank's allot guys....sorry about the novel.
