I have an 03 gt with an automatic. What mods should I be doing in preperation for my turbo 5.4. I have Sniper software so I can adjust shifting and firmness, and preasure, aside from a converter, whats next?

 

there are a few tranny places. the only names i know of are Performance Automatic and Lentech.

since your gonna have lots of torque with the 5.4 and a turbo than i recommend nothing less than a race application with trans-brake and manual valve body. im sure your power level will be too much for the mid level transmissions they sell. that stock tranny stands no chance against 500-600 torque.

 

I'd start with a low stall torque converter, 24K GVW trans cooler, oil cooler, cobra brakes (seriously...get em) hardened rear axles, PHB or Watts link, 255lph fuel pump, EGT guage. That's about the minimum. Your turbo application adds importance to most of those.

Replacing the tranny with a built c4 or even a c6 would probably go a long way to saving your day and a 9" rear might be a good idea. Stanger is right... 600tq is going to shred your 4r70w

 

plus 1 on the C4. I have been running my for the last year and havent thought about goin back to a stick. Your looking at 1/2 the cost of a built 4r70 with everthingto install it. If your looking for 550+ i would buy a performance Automatic Super Comp.

Shawn

 

If you want to do it correctly, then putting together a tranny should be one of the last things you do.