Torque Converter lockup

[SMOKNZ]

I was wondering what controls the TC lockup feature, is it the ECM or is it controlled in the transmission? I have had an issue with my truck with the converter locking while I'm accelerating on either the 1-2 shift or the 2-3 shift. This is just normal driving not WOT or anything. I was under the mpression that the TC would/should lock after you've attained your desired speed and let off the throttle some. Having the TC lock so early makes driving not real enjoyable. I have an Auto, I'd like to utilize the converter

Bill

 

[Got Diesel]

I have the same proplem sometimes. When slowly accelerating it wants to lock up at 40 mph, thus taking the rpm's down to 1200, makes it a little sluggish. If I am really tiresd of it doing this I kick it out of overdrive using the button, and kick it back in when I reach my desired speed.

 

[Ford_Forgotton]

Its controlled by the ECM, and its variable what engages it.

Typically, under light load, it will try to lock up around 45mph.

Under heavy load, it will try to lock up earlier. Slippage under WOT or heavy load is bad.

Each computer code is different. My NVK4 will lock during the 1-2 shift under WOT conditions. Otherwise it locks at 45mph regardless of gear.

If you have a PMT* code, then the locking strategy is a little different.

If you want 100% control of your TC, you'll need to cut the TC lock wire and put in your own switch. Not really recommended tho, as the computer is *usually* smarter than you are. I say usually, because there are some stupid times when it tries to UNLOCK that we dont like. (like when you touch the brakes on a downhill slope while towing).

Jody Tipton custom tuned chip and a BTS tranny and your problems are solved.