8L90 Shift Torque Factor?

[lucas287]

Do these fields even do anything for the 8L90? Stock Shift Torque Factor values are "1" across the board, nothing in the Adder cells, and nothing in Shift Torque Adder Modifier table is empty too.

Does it work just like with the 6L80? I've seen some great threads explaining the formula and how to reduce TM on upshifts.

Also, my Shift Torque Adder Modifier table only goes up to 148 lb ft on the Y axis. Odd.

STF.JPG

[ahmedabri97]

Just put 1 in the adder in gears you want to modify.
Put the percentage you want to decrease in the adder modifier table and you are good to go.

[lucas287]

Thanks, exactly what I thought.

Any thoughts on why the modifier only goes 148 lb ft,...

[cmitchell17a]

I've never noticed any change or difference when I change these tables. A lot of people I see just increasing the MIN timing table which puts a cap on how much timing the ecm can pull during upshift torque reduction, but I think this is the completely wrong "band-aid" and "lazy" way to fix it which really dosent fix anything.

I really wish we could get more support and tables that work for the 8L90.

[lucas287]

I agree. There's an abundance of information on 6Lxx, 4Lxx but this darn 8 speed....

So I tried these tables and they definitely work! In the adder modifier table itself you should put the reduction you want from a 0.00. For example 20% would be -.20. I made the mistake of forgetting the decimal at first. The shifts were unbelievably harsh at anything more than 50% throttle. Like barking the tires at 3 grand getting on the highway violent.