I have an 03 Supercrew 5.4L with the 4r70 tranny, lifted 6 inches and 35 inch tires, what should I do if anything to the transmission?

Im sure the lift and tires put more stress on the transmission and dont wanna blow it up. only have like 80,000 miles on it.

 

Since heat is the big killer in a tranny you could add a bigger trans cooler or even one with a efan.

 

And you better have larger gears in the rear & transfer case to relieve stress on the powertrain, if you have not done so already.