What is this tc lockup yall talk about. Sorry I'm a newbie

 

for automatic transmission, there is constant slip, unlike the solid connection of a physical clutch on a manual transmission.. this lead to lower fuel mileage (wasted engine revolutions)..

some engineer came up with the idea to put a little clutch in the auto converter and act just like a manual trans when the clutch is engaged (ie locked up)..

so, the computer (or some electronics) sets a signal to cause this clutch lockup to occur.. thereby increasing the use of the engine rotations as much as possible.

the sooner u lockup the better the mileage... but the sooner you lockup the less usable 'power' you have too.. (imagine trying to accelerate from a light in 4th gear.. eventually you will get up to speed..).. lock too soon you hurt performance, driveability, lock too late and u waste engine revs (and thus fuel).. finding the balance is an engineers struggle..

as an example, the Spartan tuner changed lockup to 40-45 mph.. for me towing my trailer, this is too soon.. I lost useful acceleration.. but if it were to lockup only at 65 (when on the highway) then I would loose engine revs during my mostly 55-60 mph drive to town and back.

Sam

 

Thanks, so if not pulling and only setting a mild tune what lockup is preferred or best.

 

darn good question..

you want it locked up as much as possible while you are at steady speed.

there is no one single value that is right.

Sam

 

the lockup could be different depending upon your driving conditions. Mine locks up at around 50 mph from the factory and I find that just right for where I live.

It also works well with towing applications.