Rough Shifting Automatic Trans '98 NG900S

Salutations:

On Tue, 01 Nov 2005 14:25:16 -0400, Malt_Hound not*yahoo.com">

I also bought a NG900 for my daughter to drive, only I made the mistake of buying

the GM V6. The engine (if you call it an engine) is the reason I am selling it. However, I must say the automatic transmission has been flawless. I still prefer a C900 with a manual tranny and short shift kit, especially when it is teamed up with a Red Box turbo, but this is not the car for new driver.

Fred one assumes knowing your posts that you have filled it correctly. At

Those ZF boxes are pretty good and are used in other car makes apart from GM Saabs. They should go for way longer than 90k without major problems.

Sounds like you might have trouble with the electric servo operated valves. Could just be varnish causing a valve to stick, or worse a broken or bodgy spring, or worn bore. You can damage the transmission pretty quickly operating it with faulty shifter valves.

I thought they were Aisin Warner on NG900's.Mine certainly is.

Glad to hear it, and yes, received the shipping money by PP kust fine.

Well, the good news is that it does not seem to be getting any worse. The bad news is that it does not seem to be getting any better even after 2 fluid changes.

This is a 2.0 liter FPT. It's not so much the "new driver" syndrome. This daughter is 21 y/o and commuting to her internship (college). It's the route that she's driving that makes the auto box a good idea. Rush hour in the city anywhere in the Eastern US is gridlock.

But I must say that, having driven the car on the highway a bit, it is a very comfortable interstate cruiser as well.

Thanks for the kind words. Yes, it is certainly filled to the right level. That was my hope initially, that the symptom was just low fluid level. I have even tried running it at different points on the dipstick within the "normal" range in attempt to see what it liked the best.

I am wont to bring it to a transmission shop as they usually give you the same diagnosis regardless of the actuals (rebuild). And I am boycotting the one SAAB specialist that I used to go to as he attempted to overcharge my daughter when I was away on business last year, even knowing that she was my daughter. Too bad for him.

I guess if the symptoms get at all worse I will have to find a new one (specialist, not car). In the meantime, I'll just be monitoring it closely.

Thanks,

That's encouraging.

OK. That would be nice since those should be easy to replace in situ. But could you expound on how a sticky servo valve would cause the rough shifting? I am not really up on my automatic transmission theory, but I just figured the valves re-route the pressurized fluid through various circuits to affect the shift, and the shifting seems to happen at the right time(s), just not so smoothly when it does. To me, it feels as if the clutch(es) were a bit too tight, or not slipping enough.

Are there any diagnostics or tests one can run on those servo valves?

You are correct - brain fart on my part dunno why ZF slipped out of the fingers. That same AW is also used some Toyotas.

The information about the valves is still the same.