Originally Posted by Maroon 300D

Could this be a job for Trans X?

I've never used it myself but others seem to have had good results.

I wouldn't think this is a vac problem; as far as I know the vac is only there to dampen the shifts and does not impact whether they occur or not. I wonder if this could have something to do with a varnish buildup in the valve body. That's what made me think of Trans X.

You might want to do a search on Trans X, Mr. Fix it.

Also...what is the trans switchover valve? Perhaps in my ignorance of this gizmo I'm missing the cause of the problem entirely.