Can a modern Saab gearbox seize?

Hi

Just wondering whether it's possible for a modern (1991) Saab gearbox to actually seize? The box on my 9000 cs 2.3t has been whining for a while, and now it's louder and more like a hum. Happens at all speeds, in all gears and even when coasting and with the engine off.

As the car's done 210k miles, it's not worth replacing, I'll just run it until the box fails ... however, obviously I don't want it to sieze and lock the wheels while I'm driving.

So, can the box actually seize in such a way as to lock the wheels?

Cheers

Gary Cook.

Reply to
cook_gary
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My guess is if it seizes at speed, the gears will get get destroyed. The momentum of the car is to large to be stopped by it.

Reply to
yaofeng

Gary,

Let us know how it goes. I had a '95 9k which had drop throttle whine. Apparently, that can go for a while before it dies. Your problem sounds like it is in the final drive portion of the box and is probably much more terminal. Yes, It can seize and lock the wheels. If it is really loud, it may be trying to tell you something. This is the only way mechanical beings can communicate ;-) What is the condition of the car otherwise?

KeithG

cook snipped-for-privacy@hotmail.com wrote:

Reply to
KeithG

Keith

It's not really loud ... yet ... but it's definitely on it's way out. Other than that, apart from a crackshaft position sensor that I'm having changed soon to cure an intermittent stalling problem, the car is fine ... a little bit tatty but it still drives like a dream....

It's a tricky one this, because how loud is loud?!? I mean, it could last another 10 years or 10 mins....who knows!

Cheers

Gary

KeithG wrote:

whine.

gearbox

Reply to
Gary Cook

It'll skid nicely though !

Graham

Reply to
Pooh Bear

Does it quiet down if you engage the clutch (assuming it's a 5 speed)?

Reply to
Dexter J

seize solid. Gear whine is not a positive indication of impending complete failure. Have you noticed the gear whine from some commercial vehicles? Gear whine used to be common on all forms of gears if they were rotating quickly enough, with modern gear cutting machinery annd modern gear forms we have come to expect quiet running. I think the eventual failure will be loss of drive.

Reply to
John Hudson

My 1991 9000T gearbox didn't seize, but it remained in first gear even when the shift lever was in neutral. It made for quite a surprise when I wanted to come to a stop, although the grinding noises (most likely from a broken shift fork) should have been fair warning.

This happened about 2 years ago at 130K miles. I was able to replace the transmission with a warranted rebuilt unit for US$2000. That includes the cost of replacing all the bits I broke along the way, a new clutch, pressure plate, slave cylinder, and flywheel resurfacing. If the car is otherwise sound, it would be a shame to chuck it.

Walt Kienzle

Reply to
Walt Kienzle

Hi

No, no difference when clutch is depressed...it's purely speed dependant.

final drive stage by the sounds of it ...

Gary

Dexter J wrote:

speed)?

Reply to
Gary Cook

yeah, I understand what you say ... but isn't it likely to be a bearing rather than gear whine? or is it possible for one of the gears to be deteriorating and causing the whine instead of the bearing? If it's a bearing instead of a gear failure, then if the bearing siezes or, more likely, disintegrates presumably there'd be a hell of a noise and at somepoint something would break catastrophically, or it'd seize????

Really, if I'm doing 80mph I'd like it to lose drive instead of freeze!!!

Gary

Reply to
Gary Cook

Hi

So did your start off quiet and then gradually get worse to the point where you got the grinding noises?

To be honest I'm reluctant to spend anything on it now ... it's done

210k and anything could go next! I'll run it until it stop basically...

Cheers

Gary

Reply to
Gary Cook

and the oil seals will not cope with a shaft thrashing about. If you have loads of noise and oil on the floor a bearing has failed. You will have a car that cannot be driven but not, I believe, a car that has seized in its tracks. It is usual to replace a noisey bearing before it breaks up to prevent the damage it will eventually cause, if you are not concerned as your gerabox is elderly then carry on. Good luck and enjoys your cars last days!

Reply to
John Hudson

Unless the engine is noisy or the thing is rusting out I don't really understand that mentality. 210K is just not astronomical by today's standards, my car has 265K and is still going strong, wouldn't hesitate to replace the gearbox in the unlikely event it was needed.

Reply to
James Sweet

Yeah, I know what you are saying ... but I just get the "feeling" that it's on it's way out ... not sure I want to keep sinking money into it ... especially as I've just changed jobs and have a 140 mile round trip ... petrol being expensive (and likely to get worse) I could really do with a car that does over 50mpg ...

Won't be half as much fun to drive though!!

Gary

Reply to
Gary Cook

How do you know it's a gearbox problem? If it's speed dependent then maybe it's a wheel bearing....worth a look I think especially after 210k!

Tim.

Reply to
<tim.rickettsNOSPAM

I haven't been following that closely - does it change when you go from flooring it to coasting, both while in gear?

Reply to
Dave Hinz

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