possible easy fix 4L80e converter unlock

[Vetal]

Keeping it locked and allowing the engine to break will greatly improve fuel mileage if you have DFCO parameters setup properly!

I don't think it can improve mileage more than a few % on automatic car, that has to unlock converter and go through gears when slowing down

[LSxpwrdZ]

Anytime you coast and the conditions are met to shut the injectors off it helps. This is a huge gain on mileage with alot of the truck tunes I do. You get free mileage while coasting in DFCO. Stop and go traffic you wont notice it as much due to not coasting but combined driving habbits, correct shift points, correct TCC lockup points and DFCO will greatly improve fuel economy.

[Frost]

Anytime you coast and the conditions are met to shut the injectors off it helps. This is a huge gain on mileage with alot of the truck tunes I do. You get free mileage while coasting in DFCO. Stop and go traffic you wont notice it as much due to not coasting but combined driving habbits, correct shift points, correct TCC lockup points and DFCO will greatly improve fuel economy.

I do it on my personal truck, but VERY VERY rarely do it to customers' any more... they all complain after they realize when they left off the throttle they feel engine braking vs. the truck just still driving itself on it's own down the road as OEM... I have done a fleet cal like this though.

[LSxpwrdZ]

I always make it a point to ask. So many personalities with drivers to make a one hat fits all deal. Same with shift points. Some like more aggressive than others etc. But yes you are right it does make it a little more "clunky" but if MPG goes up most are all for it.

[Vetal]

I do it on my personal truck, but VERY VERY rarely do it to customers' any more... they all complain after they realize when they left off the throttle they feel engine braking vs. the truck just still driving itself on it's own down the road as OEM... I have done a fleet cal like this though.

Do you slowdown in DFCO only in highest gear? At what speed does it shift back to 3rd?