Does the 4r70 trans have a lockup type torque convertor. I got a 02 Screw with the 5.4 engine and 4r70 trans and was wondering if it had one??

Thanks
Jake

 

Yes, the 4R70W has a lockup torque converter.

 

Yes. It will lock up in any gear besides first.

 

Thanks guys

When I bought this truck I had no infor on it. I did do a test run today and at 70 mph with the overdrive on RPM was 2K. With it switched off the RPM at 70mph was 2800.

Now if I'm doing 70mph at 2K and give it alittle gas the rpms will jump up 300rpms before the mph starts to increase. I'm thinking thats the lockup unlocking providing more torque.

I guess you could say we have a 5 speed automatic

 

That'd be the torque converter unlocking...and all automatics are designed to do it....

 

i realize this is a dead thread.... but uh, i feel like mine unlocks way too easy. is there an aftermarket one that doesnt unlock as easy? or one that doesnt unlock?

 

You can get an add-on performance chip with it programmed not to unlock as easily, but keep in mind that driveability may be adversely affected. The TC is unlocking because your accelerator pedal input is telling it "hey, I want some more torque to the wheels"

The cheapest thing to do is just to ease into the accelerator pedal more gently so the trans won't unlock the TC. You may have to unplug the battery so that the PCM can learn and adapt to your new driving style more quickly.

 

bleh, my driving habits change daily, minute to minute... sometimes i just cruise, others i nail it and show what i do have left at 185k lol. guess i will have to talk to troyer more about my tune he has in progress.

 

Mike can handle what you need with no problem. Just let him know what you are after.

Darrin