Looking into converting 1990 c1500 383 MPFI/700R4 to 6.0 or 408/6l80e

[YenkoST]

Never said it was the best performance transmission. I just said that they have there place where they are undergeared like the G8 and where city driving will be 95% of the driving that it will see, it will make acceleration easy. Not trying to compare your truck to my truck or more importantly my driving style to yours.

And personally, I dont know you so how do I know what you know. Same can be said about me but back to the original question.

Has anyone done it and what can I expect? Dont want to go with the 4L80 due to the .75 4th gear and 2.48 first gear and the 4L60 is known to be weak unless to you want to spend 3k and have it built up by FLT, etc for a 600rwhp potential and even then they are suspect at times.

[bangbangskeetskeet]

Has anyone done it and what can I expect? Dont want to go with the 4L80 due to the .75 4th gear and 2.48 first gear and the 4L60 is known to be weak unless to you want to spend 3k and have it built up by FLT, etc for a 600rwhp potential and even then they are suspect at times.

The 4l60e is weak and needs good parts to last, the 4l80e on the other hand takes more power than you will make more than likely in its stock form.

I highly doubt you will want to do the 6 speed. As far as I know you will need an entire TCM, separate from your existing PCM, to control just the trans. I guess if you want to do it that way then do it. If you're worried about gear ratio and shit like that, why not just do a t56 and have your 6 speed and not need to worry about all the other shit involved with the new auto?