SaabCentral Forums banner
1 - 12 of 12 Posts

·
Registered
Joined
·
48 Posts
Discussion Starter · #1 ·
Hello everyone! I have been chasing this problem down since I purchased my 1999 9-3 base hatchback.

I'm getting a rhythmic thump, thump, thump that increases directly with my speed. It feels like I'm driving over evenly spaced sticks in the road, and it gets faster as I drive faster.

It REALLY felt like it was coming from the passenger-rear wheel. I replaced 3 of my 4 tires, AND the rear hub assemblies last week. It is still doing it.

I purchased front bearings and have yet to install them.

Could this be a flat-spot in a front bearing? What else could it be?

On a side note, and it may be related, when I had the front wheels off the other day, I noticed that my passenger-front caliper has some back-to-front play in it...(i.e. you can move it about a centimeter forward or backward on the rotor), however the driver's side is stationary as a rock. I hear a thud from that wheel sometimes when I back up...

Would this be related?

I am stumped. These cars are so solid, it's difficult to determine WHERE drive-train/suspension noises are originating from.

Has anyone else run into this?

There is no side-to-side movement or up/down movement in either front wheel when jacked off of the ground. There is no skateboard or grinding noise that is usually indicative of a bad bearing, although the thump, thump does make a bit of rattle in the interior.

Thanks for reading the long post, and for everyone's help!!!!

:)
 

·
Registered
Joined
·
48 Posts
Discussion Starter · #3 ·
I'd make sure that caliper is secure, are you saying there is play between the bracket and steering knuckle, there shouldn't be and that would cause a noise like you describe.

I'll check that! That wouldn't cause an actual, continuous THUMP (that increases with speed) though, would it? Clunk while braking -- yes, but a rhythmic thumping?
 

·
Registered
Joined
·
48 Posts
Discussion Starter · #5 ·
It may not be the source, but it's something that is obviously wrong, so fix that first and then move forward.
Very wise! I know, I sound cheap! This wonderful car (I really love it) has been squeezing every last penny out of me. In retrospect I probably shouldn't have purchased it, as I don't really have the funds to do it justice at the moment, but I'm trudging along, mostly because of the excellent help on this forum!
 

·
Registered
Joined
·
48 Posts
Discussion Starter · #7 ·
Also if you jack up the front end and run it in gear with the front wheels turning it might be easier to locate the noise, or at lease tell if its front or back.

Thanks! What's weird is that it's not a noise, per say, but more a physical FEELING in the car.
 

·
Registered
Joined
·
48 Posts
Discussion Starter · #9 · (Edited)
Solved

A centimeter of movement? Or a millimeter?
It was a few millimeters, apparently...

First off, I want to thank everyone for taking the time to answer my questions! I figured it out, and I feel like an idiot.

I haven't had a jack, my garage was robbed recently, and all of my tools were stolen. I haven't had the ability to take the wheels off this car as much as I would like to in order to diagnose problems.

The caliper movement was due to LOOSE bolts. Both of them were backed out a fairly significant amount; luckily I think I caught it before it did any damage to the caliper mount. The rattle is gone, and there is no more give or movement to the caliper. (That was a simple fix, thank my stars)

The second problem was not a bearing at all. It was the simplest thing of all and a lesson I wish I'd learned years ago. (I need to stop diagnosing my new-to-me cars by myself)

It was a flat-spot on the driver's-rear tire! The kid that owned this car before me beat the hell out of it, and didn't maintain it properly! To me, it looks like someone was showing off with the emergency brake and donuts!

(I SHOULD HAVE REPLACED ALL 4 AT THE SAME TIME!!!) I was broke though!

Anyway, I got a GOOD used tire INSTALLED for $25...at least that will get me through the winter! Furthermore, NO MORE ANNOYANCE! AND, my wheel won't fall off!

Now I have a spare set of front-wheel bearings in case I need them.

Thanks again to everyone on this forum for being so helpful, and making me feel like I'm part of the community! Cheers!!

 

·
Registered
Joined
·
48 Posts
Discussion Starter · #11 ·
I don't know if you did it, but the Caliper mounting bolts are supposed to have blue loctite on them. You aren't the first guy to report a loose one.

Thanks! I am going to pick some up on Thursday and put it on the bolts! I figured it was supposed to have it because it had red loctite on the bolts when I took them out to clean them up on the wire wheel!
 

·
Registered
Joined
·
1,871 Posts
My '99 9-3 base is thumping on the passenger side as well and it's variable with wheel speed. It's more noticeable when turning slightly to the right like when exiting a freeway. I assumed it was a separated cord on that tire so I switched the back to front but thumping persists. Stanchion bushings and control arms were recently replaced and that wheel shows no movement from a worn bearing.

I suspect the CV joints/ axle are causing it and there is noticeable lateral play (in/out) on that side, probably 1/4", and when pulling-pushing on axle it makes a noticeable metal to metal click. The driver side axle's lateral play is almost nil, there is only the slightest movement and no noise.

Could this play be causing the thumping noise on the passenger side?

Thanks.
 
1 - 12 of 12 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top