suspension question (c900)

Hi,

I'm concerned that the suspension on my 1992 900 might be on the way out. First of all, the rear of the car simply looks lower than the front. That's not normal, is it? Unless all those corpses in my trunk are weighing it down :)

The other thing is that when I have passengers in the rear seat, the rear suspension seems to bottom out regularly.

So, I'm wondering what I should be doing. Should I replace the rear only or also the front? And what parts exactly need replacing? What special tools would I need?

On a related note, I noticed that the front tire on the left side seems to be wearing on the outside edge, whereas the right front tire isn't as much. Could this maybe be a ball joint issue?

I don't know a whole lot about the suspension, and would appreciate any enlightenment.

Thanks,

John

Reply to
John B
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I've noticed this a bit with my car (1983 900S), but I do know that the bushes for the compensating links at the back are shot and will need replacing soon. However that shouldn't cause too much of a problem with normal driving. It probably depends what 'normal' means. 8-)

Something I'll be doing later this year is replacing all suspension bushes with poly ones. Superflex makes bushes for C900's so you could look at using them in your car too if you're going to do a full suspension upgrade at some stage. In my case I was looking at replacing the shocks and the springs too, but that's a very expensive proposition to go 'whole hog' with heavy-duty Bilstein's and one of the many springs kits that exist. We have a really good spring manufacturer here in Australia (Lovell's) that lists C900 springs in their catalog.

Have you checked the balljoint boots lately? Like CV joints, the boots protect the workings and once they get compromised the workings fail quickly. I know about that from the CV joint problem I had with my car a few months back. 8-)

Neither do I, but there are some very good websites that cover general suspension issues and some saab-specific ones as well.

Regards,

Craig.

Reply to
Craig's Saab C900 Site

The CV joint does not affect the angle of the wheel, camber or toe.

But old 900s like yours like a lot the boots. No wonder they had a tight turning circle. By the time I understood I had to change them too regularly it was too late to see if SAAB original parts would have lasted longer.

Regards Charles

Reply to
Charles C.

A common look of many classic 900s. The rear springs are likely to need replacing.

Consistent with the springs gone.

From the sound of things I would say you cannot handle it yourself. Sorry.

[NB. The most knowledgeable on the recent c900s correct me].

It is an easy job to do if you have been doing other work on cars. When I did this on a 1983 900 I needed two of everything. 2 hydraulic jacks and two pairs of spring clamps/compressors. You also need stands which you could use to support the car with (not the axle).

From memory you have to remove the bottom bolt of the shock absorber and then remove the bolt of the trailing arm.

Are you in a left hand or right hand drive country? The left tyre is more likely to do what you say on a left hand drive country.

How many miles has the car done?

Yes it can be a ball joint ... it can also be:

- a steering knuckle joint (the ball joint at the end of the steering rod);

- simply incorrect toe alignment (could happen with use and occasional meets with curbs etc);

- other much more expensive things.

Basically the wheel is having to turn slightly to the right in order to keep the car going in a straight line. On a left hand drive country the camber of the road + wear and tear on the ball joints (all 3 of them on each side) is enough to produce the results you see.

I would look for a bad ball joint and replace. It can be on either side of the car. It can be more than one joint.

Hope it helps a little.

Regards Charles

Reply to
Charles C.

Ok, good to know.

Oh, I've done lots of car repair projects that I can't handle myself. It usually makes for an interesting mix of frustration, excitement, and rapid learning :)

Ah, Ok. I am in the US. And these are old tires which will need replacing soon anyway.

Roughly 126k miles.

Thanks for all the input. I think I might have a go at replacing the rear springs and shocks, and decide what to do about the front end after that.

John

Reply to
John B

There might be two kinds of springs. Ordinary and heavy duty. I chose the latter, the car stood higher than normal but gave a lot firmer ride. It was good fun to drive but not "normal" looking.

Then it is easy then ... but that is not the impression you gave. Unless you have a real large spring compressor you will need two pairs. Clamp the spring before you release the suspension but once you have it out you will not be able to release enough the clamps to take them off the spring. This is where the 2nd pair will be needed. ANd the reverse for compressing enough the new spring.

You need two jacks ... one to control the axle and the other for the trailing arm. Necessary for refitting as it is not easy to get the trailing arm back in position.

I think you have to look at the front too. If you are in the US and the front left is wearing then there should be something a little bit faulty ;-)

Reply to
Charles C.

I might take this opportunity to upgrade to better-than-stock springs/shocks. Being that this is a non-turbo, it seems like perhaps the best possible upgrade for the car. I've heard lots of good things around here about combining Koni "Special" shocks with Eibach progressive springs, so maybe I'll go that route..

Yeah, I'm definitely no pro, but everything I've replaced (clutch master, V-belts, brake pads/rotors, exhaust, heater valve, headliner, other misc. things) is miraculously still working.

Ah, thanks for that! You probably just saved me a fair bit of frustration.

I'm guessing that I'll need a ball joint fork when I do the front end. The Bentley manual mentions something about a "special tool" for that purpose, which I assume (like many of the Saab special tools) is not 100% necessary.

John

Reply to
John B

springs/shocks.

Take extreme care when using any form of spring compressor, a compressed spring is lethal if it escapes.

Reply to
John Hudson

I can well imagine. Thanks.

John

Reply to
John B

Standard practice is to put a loop of chain through the spring and connect the ends with a bolt while you compress/decompress.

Reply to
gw

Could you clarify that a bit? Do you mean that the chain is just long enough to allow complete decompression of the spring, but no longer? Or is the chain shorter, keeping the spring fully compressed if it were to get loose?

Thanks,

John

Reply to
John B

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