I put a bully dog triple dog on my 4.6 and noticed it had a firm shift option. i put the firm shift on yesterday and you can tell the difference in the shifts. i am wondering if this shift hurts the trany.

 

It is better for your trans. The quicker the clutches engage the less ware you will have on them.

 

^^^^X2 I have my Evo shift firmness set to +10 on all gears

 

This is true but, what does it do to the planetary gears and thrust washers? Any added stress do you think?

 

mine are smooth as silk after 60k miles of firm shifts.. matter of fact just changed the diff oil and all looked great inside..

 

Awesome. Still curious if it stresses the planetary gear sets and thrust washers in the trans?

 

I guess I always thought it wasn't too great for the Trans to run the firm shifts also. Might have to try it for a little while.

 

You'll love it just have to figure out how firm you want them had to adjust mine a few times now I have it at +10 on all gears and I like it.

 

i had got the programmer to save fuel on my truck but its so fun to drive! it feels like a whole new truck!

 

Ain't that the truth - "like a whole new truck". Same for mine but with an Edge Evo.
Better mileage??? Some say yes. I couldn't measure any improvement although I do get better than the Ford estimates. I average 18.5 combined.