HELP! new transmission and problems

[Preacher]

Have a THM 400 (Summit) and it has less than 1000 miles on it. It has now started slipping bad in 3rd gear - especially at WOT

1. vacuum modulator good, not leaking and receiving vacuum from back of intake
2. kickdown wired correctly 12v @ WOT
3. trans fluid good, clean and full
4. ??????

 

[LS6 Tommy]

Screen is dirty?

Tommy

 

[SSedan64]

A pressure check will help locate the problem.
0-300psi Pressure Gauge. Test Port is on driver side about mid pan area.

http://www.amazon.com/s/ref=sr_nr_n...=1358032851&rnid=15690151&tag=maliburacing-20

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