I am running into trouble with a 6.0 4l80 combo hitting limiter on 2-3 shift it is not being commanded I've tried everything i can possibly think of wot set to 4800 I've tried 4000 it just wont command until 93mph I am running it in 4 low 5.13 gears reading from trans output vss wondering if its just not possible for the pcm to shift fast enough. tune and log posted 0411 512k cos