Tuning questions: 4.3, nv4500 to th400

[Redmansfield]

I purchased a 97 c1500 extended cab. Was originally a 5spd, the guy converted to an automatic, shifter on the floor. Th400 trans.
He had 32s on the truck, I recently went down to 28s. +1 to stock size. I am Noticing a pretty significant difference in the speedo. And I am also going through the truck and fixing pretty much anything that's wrong.
I want to do a tune, and fix the speedo. But I'm wondering since the transmission isn't electronic, is a tune going to do anything for me?

 

[chillman88]

I had mine tuned back when it was still an auto and it had better response all around, not just pertaining to shifting. did mine and even for a stick shift id have them do it again. Made a noticeable improvement.

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