Okay, I hope I don't get flamed too much for having a V6 700R4, but here goes nothing:

I've been having a problem with the lockup clutch on my 700R4 for a while now. Sometimes it will lock, sometimes it won't. The problem is worst when trying to maintain around 60 MPH, but it also happens just about anytime the TCC engages. I have checked the fluid level and topped that off, replaced the ECM, adjusted the TPS and TV cables, and I am getting kind of PO'd now because the clutch disengaging at 60 means that I am riding around at around 2500 RPM and using way more gas than I should be.

How do I troubleshoot the clutch, and/or what hardware is involved in the engagement process?

 

Could be a bad solenoid or pressure switch inside the trans pan, have to drain fluid but not hard to replace. First try pulling back on the brake pedal when the TCC is acting up, if you're real lucky, it could be a mis-adjusted release switch on the brake pedal arm.

 

Check the connector at the tranny, mine was corroded, spray with a electrical contact cleaner. If still corroded or rusty clean contacts with a very small screwdriver or scribe. Do not flatten contacts.

 

Whew, been a few days here...

Anyways, I adjusted the brake switch to a point where it works correctly. Now, I still believe that this is somehow temperature related. If I am crusing down the road (just a plain, flat road) at 60MPH, with the temp needle sitting between the third and fourth marks after 100*, there won't be any problems. Now, if I end up stopping for traffic and the temp rises above that next line, even ever so slightly, the TCC will act up again. If I pull up on the brake pedal (damn difficult BTW), nothing happens. Since I am probably going to have to change the filter soon anyways (WTF knows when it was last done, if ever in all 207K the trans has on it?), what do I need to do down there?

It also seems like the TCC is locking when it shouldn't be and unlocking when it should be locked. The clutch kicks in if I am at 45 MPH and want to accelerate rather quickly. The same happens at 55+, when I am sure the TCC is supposed to unlock for torque multiplication, right? At 60, if I accelerated from 45, I can be in either 3rd gear locked-going at a constant speed around 2900 RPM, fourth gear unlocked-also going a constant speed around 2500 RPM, or fourth gear locked (still depending on temperature), accelerating at around 2200+ RPM . I don't get it.