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& all it took was a rebuilt tranny

Ouch. What about it caused the vibration?

the problem, I belive was on the differential. there is a cilindrical piece that goes across it, is it the pinion gear? well that has a pin that hold it and it fail so the piece started moving out to one side, & I belive that caused the shake. but that is only my hipotesis. you see other than worn clutches, that was the only problem the mechanic found. he did change a bunch of stuff inside, but only for prevention & some other stuff for performance.

Anybody else (who does their own tranny work) wanna take a stab at this and verify whether or not it is indeed the root cause?

That would be awesome if we finally found the solution.

Ken_W

The Diff Pin walking out is a common thing on these transmissions. Ask willwren, I believe he's had 2 or 3 do that.

It might be the cause for some, but not all. Don't get your hopes up too much Ken. I don't think there's one cause for all the different cars that have this issue.

I had the diff pin go out on mine 2 weeks after buying it. I didn't have any vibration, just a whine.

Again, I'm not saiyng that this was the cause. But it was the only mechanical problem found inside. And it would seem to me that a piece that rotates at high speeds if not centered & balanced properly, it would start to vibrate.

I had the pin walk on mine also and never had tha vibration. Right now I am starting to get a vibration, but I know mine is from a bad axle boot leaking grease.

Right now I am starting to get a vibration, but I know mine is from a bad axle boot leaking grease.

Huh? That shouldn't cause a vibration.

Why not, if the grease is gone or insufficient, and the metal parts start wearing. Now think how fast the drive shaft is rotating at 70 MPH?

We will see if it is gone on Monday when I change it out.

2000Silverbullet wrote:

Right now I am starting to get a vibration, but I know mine is from a bad axle boot leaking grease.

Huh? That shouldn't cause a vibration.

actually it can cause really bad vibrations in bad cases... I have a case of it right now on the van... I have to replace my passenger side axle.... I checked it and its in failure mode, way too much play... Bad CV's can cause some nasty shudders or a not so friendly shimmy... I believe I am having the same issue with the 03 Bonneville, I checked the passenger axle on my 03 and did not like the play it had...

What I don't understand is how come my 91 LE and 95 SE are on the original axles with no issues at all... A friend is at 230k on his Park Ave and still on the original axles... When I did Mariks trans in his LeSabre I used Sandrocks old axles from his SSE Bonneville"( 130k ) and no issues there either... Were the older H body Axles better?

I can understand if the CV joint is worn but if just a little grease has leaked out due to a bad rubber seal, then not.

Matt, I lost a ton more grease than that pic you showed of yours, and I drove 1,500 miles home from OR like that with no vibrations. It didn't have time to wear out.

This car has 141k miles on it. When I pulled the half shaft, I could feel both joints were a little loose and sloppy. I took the old one in to Napa with me for the core and you could feel a big difference between the tightness of the remand shaft and the old one. In the old one, the outer joint had a spot where it felt like there was something catching. Felt like a click when wobbling the joint.

So, the axle took care of a lot of the vibration. I drove it over and had the tires balanced and now there is no vibration at all. I watched them balance the tires and 2 of them had weights removed and one added. I think I am going to do the left one next just to stay ahead of the game.

Wait. There should never be more than one weight on a side of a tire, unless the tire is so out of balance that it requires more weight than the biggest that the shop carries, in which case they'll be butted up to each other (and/or the tire should be re-positioned on the rim). Please tell me that is the case, if not, take them back and have them do it right.

No weights on the outside. I have the stickie weights on the inside that are in .25 increments.

Ahhhh. I assumed you had pound on weights I guess. I have stick-on weights myself.

Back to topic. the shake you had would be noticeable only between 60-70 & then go away again when you went over that speed?

It was not a bad shake, just a little shimmy. I have never really had a bad shake.