2000 Bonneville SE 149k with loose axles?

[fritcr]

Ok I bought this older Bonnie and was going to use it for my DD. I have bought some parts from harofreak to fix it up a bit but I have this awlful shake that comes and goes at just over 70mph. It has brand new tires that I have paid to have road force balanced and checked 3 TIMES. Two different places. They swear the tires are perfect. I put new axles shafts in it. One is new and one a rebuild. (that's all they had without ording one)
But here is the thing...if I reach up and hold the axle or CV joint where it goes into the tranny on both side there is all kinds of play there. At first I thought maybe they were all like that so I put my daughters Grand Prix up on the lift with the same engine/tranny and it is completely solid! (it is my old DD car and it drives soooo smooth and quiet)
So does anyone have an idea what would cause this and what I can do to fix it? Would this cause my shaking/vibrations?
As always, thanks much for all of the help!
Rob

[Jrs3800]

You should have some in and out play of the tripod on the trans, the CV can seem to have a little as well, But you can't have any radial play... If you have any radial play the axle is junk..

[fritcr]

So if it moves around in the tranny...like up and down and all around...lol then it is bad? So I just put 2 bad axles in this car? One is new and one is rebuilt. One is much worse than the other. I will have to look at the ticket to see which is which as far as new/rebuilt. That pisses me off. Do you think there is something wrong with my tranny?
Sorry for all of the questions.
Rob

[Jrs3800]

Hard to say without being there to look at it... They all have a hair of play but I have never seen one that had a lot... Do you have a better description of what kind of play you have?

You might have a little bit of rotational play, the shaft move move in and out a tad, but the tripod should be pretty still and solid...

Also is your bonneville a 2.84 or 3.05 ratio?

[fritcr]

I didn't know that there were different ratio's so I can't answer that. But if I reach up (especially on the Drivers side) and grab the cv joint (is that the tripod?) is the the inner CV joint itself...I can wiggle it up and down...quite a bit actually. Both sides do this but esp the drivers side. It is all very loose. My daughters Grand Prix (my old car) is very tight and not loose and all. It drives so much better than the bonnie and I just don't think it should! My bonneviile just shakes like a little earthquake between 70-78 ish. It makes my dash shake and the seats jiggle. It DRIVES me nuts and it seems to be getting worse.

[Ken_W]

This sounds like the famous "60-70 mph shimmy" that about half of our cars have. More like the 70-75 mph shimmy on my two Bonnevilles. Has been talked about extensively on this forum.

Info here (under Chassis section): http://www.pontiacbonnevilleclub.com/fo ... 18&t=25362

Ken_W

[fritcr]

Yes I read all about that shimmy thing before I posted this. I have checked and had checked all of these componets on my car. I also have had the tires road force balenced 3 times and the tires are brand new with the little knobies on them still. 2 times by one shop and 1 time by a difference shop. Had them check for a bent rim and a tire out of round and both shops swear there is nothing wrong with the tires or rims and they balenced perfectly. That's why the only thing that seems weird are these axles. They have me worried. Do you think they could have gave the wrong axles for my car on both sides. I got them at the same time but wouldn't be highly unlikely that they would even fit and work at all?
Thanks sooo much for all of the help!!
Rob