BIG_D_74

Finished up my 4l80 swap into my 01 Sierra. The transmission is slow to downshift from say 3rd to 1st when driving at 30. It will shift to to second gear and flash the converter and then finally shift to first. Is there a way to make the transmission downshift faster? My 4l60 would downshift lightning fast compared to this 4l80.

I've attached my tune. Any input would be appreciated.

Vortec350ss

iTrader: (20)

I think thats just the nature of the beast... I finally have mine in and working right, and it behaves the same way.

03sierraslt

iTrader: (22)

Mine downshifts fast but not as fast as a 60e. It's the nature of them as they are much heavier and are designed differently. If yours is pausing in 2nd long enough to flash the converter then that sounds excessive.

Suburbazine

Mine sometimes pauses long enough to flash the converter as well (3rd-2nd at 25, 2nd-1st at roughly 40). I'm getting it looked at tomorrow but I'm thinking it might be the nature of the beast.

AKlowriderZ71

iTrader: (22)

The 80e has to downshift one gear at a time, it can't skip a gear like the 60e. At least that's what I've experienced and been told by builders.

03sierraslt

iTrader: (22)

This is in fact true, to help matters downshift manually to 3rd before punching it. Manual 3rd is stronger anyway.

BIG_D_74

Great that seems like the consensus from everyone. Makes me feel better! Thanks everyone for chiming in!

slow67

iTrader: (2)

There are ways to make them downshift faster (hydraulically).

black00chev

iTrader: (2)

What if your 4l60 sometimes downshifts like this?