just install 4th super servo few days ago.
it was working fine when I first installed it. i felt 4th gear.
now i have no 4th. i have to let off gas to get into 4th gear, and as soon as i put light throttle it will slip down to 3rd and stay there until i let off gas again!
Please help!
could it be tuning issue? because my truck has been tune several time before servo due to other mods. or is it mistake during installation? had hard time pushing in servo cover.

 

Your tune should not be effecting your servo. Look at your trans data to see what the computer is telling the trans when your truck does what it does. I would pull it back out and make sure that one of the seals is not cut. I do have the seals in stock if you need them. Vince

 

Like Vince said, the seals can easily rip when inserting it pack into the trans. Make sure you use liberal amount of trans fluid when putting them in.

 

trans gel is your friend here.....

 

Stp oil treatment + trans fluid = very slippery assembly lube. Sounds like an install problem though. How many miles on trans?

Dave

 

got about 42,000 on the truck, put back stock servo, works fine. but I got another problem. when I floor gas. down shift to first gear and come back up to second and downshift again.