Swedish Massage

I'm trying to troubleshoot a vibration on the $50 Saab. The vibrations occur when accelerating or climbing a hill and is most pronounced in 3rd and 4th gears between 2 and 3000 rpm. The frequency of the vibration does not seem to increase with vehicle speed.

I have checked the half shafts and the boots are intact. I tried wiggling each joint fore/aft and up/down and the joints don't seem to have excess play. There is some play in the direction of the shaft, but I believe this is normal.

The car appears to have new front engine mounts (score! ), but I haven't crawled all the way under to look at the rear mount. I have noticed that the gear lever moves 1/2" or so between acceleration and deceleration. Could a bad rear mount cause these vibrations? Anything else I should check?

Lol, you guys crack me up (Re: thread title). That is all.

look into tripod bearing and inner driver. I believe that was the discussion i remember when i was driving Saabs of that generation. There should be a discussion about it on saabnet.com

We had that rear mount go on Alfas version of the 9000.

Yup, sounds like a worn CV joint or bearing.

Bad motor mounts can compound this and many parts store mounts are E36 M3 and fail quickly.

I would contact drivelines inc or raxles.com and get some new axles in there before they get worse and then add pourable polyurethane or window weld to the motor mounts.

If it were the CV joints would't the vibration increase with speed (axel RPM) though? The Tripod bearing/inner reciever is just the fancy Saab term for the inner CV joints that plugs into the transmission, yes?

It's not a bug, it's a feature!

I always like play in the direction of the shaft.

The frequency should go up with speed, but its not a rear steep curve, being wheel speed. Inner joints are always the first place I look for that type of problem, and quite often there is no real evidence of boot failure. Volvo, for instance, seems to spit a wee bit of grease out of the big clamp on the rh axle, and about 200,000km in, its all gone. Pop the big clamp off, fold the boots back and see if its dry inside. Be prepared with new clamps if it turns out to be fine.

Is there any way to check for play on the inner joints so I know which one to start with, or should I use eeny meeny miny mo?

I go with my butt feeling. A Volvo, I can guess right about 80% of the time, test driving and concentrating on whether the shake is from ahead of me, or off to the side.

In reply to Streetwiseguy:

No talking about feeling your butt in a thread about Swedish massage.

Since I have only ever owned one FWD car I can't claim to be an expert, but for what it is worth, this is how I was told to diagnose a failing CV joint:

In order to easily diagnose if the sounds are coming from the CV joints, the user can turn the steering wheel completely in one direction and back up slowly. If the noise gets louder and more consistent, the user can safely assume that the CV joints have become compromised.

Read more : http://www.ehow.com/list_5963234_signs-bad-cv-joint.html

In reply to NOHOME:

That's good for outer joints. The inners generally start to shake long before they make any noises.

I have nothing to add other than hopefully you'll get a happy ending.

In reply to JohnRW1621:

Diagnosis

see if this helps. I had another link somewhere if this does not point you in the right direction.

Chris

Thanks guys. The butt-o-meter says it feels like the passenger side. The inner driver for the passenger side is part of the intermediate shaft, so it will take some searching to find that. The Saab forum also suggests getting the tires balanced. I doubt that is it, but this thing has sat for over a year so it can't hurt I guess.

I think you can buy the whole axle for areound 60/side.

In reply to cdowd:

I have seen people say that on old threads in the Saab forum, but all the pictures on the autopart websites look like this for the inside of the passenger axle:

axle

I think you this is what you need.

CD

See if there's a spec for play in the CVs in the FSM before you start throwing parts at it. Check the mounts. How's the service history on the ignition system? Weak spark issues show up under load.

In reply to cdowd:

That's the driver's side. The passenger side would need to look like this to come with the inner driver:

http://www.ebay.com/itm/Saab-9-3-03-07-2-0L-A-T-Right-Passenger-CV-Axle-Drive-Shaft-12-801-439-/331571553504?fits=Make%3ASaab%7CModel%3A9-3&hash=item4d333464e0&vxp=mtr

In reply to Kenny_McCormic:

Ignition system just tested, and new spark plugs installed. It sparks like crazy:

http://vid414.photobucket.com/albums/pp221/bgkast/20150511_204633_zpsxwnpunqm.mp4

Looks like the inner joints have some play. When you hold the inside of the inner joint the wheel can be rotated half a degree or so. My neighbor traded me some used axles, and they feel nice and tight, and the boots are intact but some grease has leaked out of inner joints. I plan to re-pack the joints, should I replace the boots at $20 a pop too? Anything else I should do?