sudden transmission problem

[shelfont]

Hi. I have a '90 Bonneville SSE and after coming to a stop at a red light on the highway, when the light turned green the car wouldn't move forward. There were no odd noises, the car had been in cruise control and there had been no problems up to that point. The car shifted crisply, there was no obvious slippage or hesitation going into gear.

I can feel the car engage in both drive and reverse, but it won't move at all.

[maxwedge]

Make sure there is no brake lock up, get the front and rear wheels off the ground see if the wheels turn freely, make sure the axle is not broken, basic tests, if all is ok it's done.

[shelfont]

Thanks. The car rolled freely to push it off to the side of the road, and there were no odd noises that would indicate a broken axle. My understanding is that there are various electronic parts that are prone to failure in this transmission. Do you know of any specific things that I should be looking for?

What makes me wonder is the fact that this just happened with no warning. Came off cruise control and that was it.

[maxwedge]

There is no electrical component that would cause the trans not to go into reverse or drive. If it is full it is an internal issue.

[Jrs3800]

Thats an internal issue... You may have blown a Lip seal and may not have enough pressure to apply the apply pistons or the clutches for that matter...

There are switches on the trans that the ECM uses to know that it can apply the TCC... The only electrical component on the THM440-T4( 4T60 ) is the TCC Solenoid... None of those will cause the trans to not apply... sounds like an internal issue...

[Tech II]

Assume you checked fluid level and condition?