NG 900

At 70mpg I could live with a little shimmy.. (sorry, someone was going to jump on that one)

My 900s (1998) only gets about 30mpg, but assuming that you meant 70mph, it *will* be wheel balance or a bent wheel. Brake disk warpage will sometimes cause wheel shimmy, but usually at a much lower speed.

What...you only get 30mpg??? Yes, I meant 70mpH. Good news...balance or bent, thanks.

MKW

I had a NG900S that had slight "shimmy". I took it to a trusted Saab shop and I was told this was normal for the NG900s. The design of the NG900 suspension changed from the Classic 900s, which is why the "shimmy" was so noticeable. You can take to a shop and have the wheels checked for bent rims and out of balance. You could get the front end alignment and the steering rack checked for your peace of mind. It did not cost me anything because the car was under warranty at the time.

Other issues with the car led me to sell the NG900S. Check the forum for other posts on issues with the NG900 design. Expensive repair points to look for: automatic transmission control module, GM V6 engine, AC system design, minor and major electrical failures.

H> What...you only get 30mpg??? Yes, I meant 70mpH.

Thanks. It's got 5sp manual, 4cyl 2.3l, but it does have an electrical and AC system.

Thanks Again.

MKW

Abbott Racing in the UK

sell a steering rack clamp kit for the 900/9-3; perhaps it is to solve this problem?

ma_twain wrote in news: snipped-for-privacy@yahoo.com:

I've got a 1997 900SE (manual, 4 cyl turbo). I've don't have a problem with shimmy at 70 mph. Or 80 or 90 mph or higher for that matter. Check air pressure and tires for signs of uneven wear.

Had exactly the same problem with a 96 model NG900 several years ago. Wheel balancing didn't help, the wheels weren't bent (had them tested for trueness). I was convinced that it was therefore a drive shaft problem especially since it seemed to be more pronounced on left hand turns than right hand turns and at certain throttle openings.

I was expecting to fork out largish $ for drive shaft surgery so I was pleasantly surprised when my mechanic told me it was just a loose pinch-bolt. Cheap fix for me - though your mileage may differ.

You were told a load of crap. I own 2 NG900's and an '03 9-3SS. None of them have any sign of a shimmy, slight or otherwise. There is nothing wrong with the NG 900 suspension design.

I had a 2000 9-3SE convertible for a while that had the original 16" wheels on it when I bought it. It had all sorts of shimmy and vibration when I bought it, which was one of the reasons I got it cheaply.

The OE wheels on those car were way too soft and in 60 k miles had become badly out of round. A new set of wheels (and tires) and it rode nice and smooth. I sold it soon after for other reasons...

NG900's do not always vibrate but they are very sensitive to any problems with the suspension. When everything is right, they are smooth at all speeds. Possibilities, in rough order of occurrence -

- out of balance wheels / tires

- bent wheel(s)

- bad tires

- outer control arm bushings worn (typically only vibrates under acceleration but there are exception)

- inner driver(s) worn (again, mostly under acceleration)

- stanchion arm bushings worn

- brake problem causing shimmy (most brake problems only occur when braking, typically at higher speeds).

- CV joint (typically has other common CV joint symptoms)

- subframe loose

- loose steering rack mounts

Unless the problems are only under braking, have the wheels and tires balanced on a Hunter GSP700. It doesn't matter if you had them done by a top-notch wheel guy - unless it feels perfect after that, you need to get the road force balance done on a GSP9700. Costs no more than other balancing and there _is_ a difference. Trust me.

to find one near you. The GSP9700 will not only fix any balance issue that can be fixed, but it will give you specs on wheel trueness and out-of-round. It will also give you numbers on the tire's problems (uneven road force). If you have problems after that, post again with most specific e.g. only under acceleration, braking, etc.

Great note...thanks for the thoughtful reply. I will follow thru in sequence and let you know what happens.

Thanks again.

MKW