Does it feel like a u-joint thunk?

I've got the same sort of clunk, only between 20-35 mph, letting off the throttle after babying it.

 

No it does at when you slow down kinda quick and at almost a stop its a hard jerk.

 

And what is a upgraded sonnax tcc switch? I looked at it on patc website.

 

Does it do it if you coast down to very low speeds? (foot off the brake)

TCC switch just gives better flow to apply/release circuits. Designed to reduce/eliminate apply shudder, and a few other issues.

 

Will I have to disassemble the vb to put that in? I haven't tried like that but it doesn't seem to do it if I take a long distance to stop. It's when I stop somewhat abruptly.

 

Wonder if you just have some bushings in the suspension that are marginal.

Not sure just where it goes.... I would think it just replaces the TCC solenoid in there now. It is *possible* to change those solenoids without dropping the vb, but, not sure if that would apply in this case.

 

I don't mean lock up the brakes, like my road the speed limit is 55. If I'm doing that and slow quickly to turn in right around 5-7 mph by my GPS I get hard jerk. Like its slamming out of gear or tcc.

 

#6. "Improved Torque Converter Lock-Up Clutch Switch Valve." The circuit timing of applied vs. release pressure exhausted is critical for proper TCC operation. The OEM valve stroke contributes to soft TCC apply, shudder complaints, and increased damper spring loads. Replace the OEM switch valve with this Sonnax’s switch valve. The new Sonnax switch valve improves the timing and flow to the apply and release circuits. Fits 42 / 46 / 47RE / RH . Cost $17.00

 

Every bushing minus the sway bar is new also.

 

If you were closer, I would have you take me for a ride.

You could disable TCC, and see if that made the problem go away. (cut one wire. will set a code though.)