Just wanted to ask I have got my ECM programmed but I'm still not happy with the way the truck responds some times. It seems like sometime when Im crusining at 75mph I step on it and it responds good but most times it lags. Will this go away if I put a vett servo it seems to me like the truck doesn't down shif sometime and sometimes it does. What do yall think?

 

Oh I forgot to mention I have a 2003 GMC Z71 5.3 with the wait-4-me program.

 

bump bump

 

vette servo i think only affect the 1-2 shifts. go invest in a transgo HD2 shift kit that might help. if it doesnt down shift sounds like you might be having bigger problems than just lag though

 

The tranny is gonna take about a full second almost to downshift...theyalways do when there stock in these trucks.The vette servo will help you on hte upshift on the 1-2 and 2-3 but it won't help you downshift any faster.If it will sometimes downshift but at other times not then you need to have it retuned to downshift at a hgiher mph.I have my downshift points set to 40mph for 1st gear and 80mph for 2nd gear.
Hope this helps some.

 

so you downshift back into first when you hit 40? seems like that would be a pretty nice rpm jump when you are trying to slow down. like a manual letting engine slow you instead of using brakes

 

I had my trans set like this too, it really went on the highway when you punched it doing like 70 and it drops back to 2nd.
But I changed it back because I've heard the 4>2 shift kills a stock 4L60 real quick. I think its just too much of an rpm change for the trans to handle.

 

Try a Superior(sp) shift kit.. they are cheaper and you get the same thing as a Transgo.
Im gettin a Superior SK and Billet Servos from a local trans builder, $180.

 

Nonononono it only downshifts back into first at 40mph if i floor it.Those numbers are if i floor it...it willl drop back into first if i am goin 40 or slower and second if i am goin 80 or slower.

 

I still have mine like that because my tranny is built.If not then it would make me a little nervous probly.I love doin 40-42..since the built unit went in it downshifts a little higher than the ecm tells it to lol...andi it drops to first.Makes for a nice wtf look on the other guys face.
It is set for an 80mph drop into second but like first it will go as high as 82.
Its fun i can tell ya that.
Now if only i had the money for a LQ4.......