just wondering whats best to keep it in around town under 60 mph, i dont think there is anything wrong but sometimes when i slow to 20ish then give it gas it isnt smooth all the time, not really a clunk by kinda like that maybe its between shifts

 

around town I prefer 3rd because in D it ends up running at 1200-1500 rpm all the time which is too low IMHO. also 3rd gives me a little engine braking when I back off the throttle which I don't get in D. sometimes when I want to get the revs up a little I'll even slip 'er into 2nd and upshift manually. the stock shift points seem awfully low to me.

 

Yeah, there's nothing wrong with cruising around in D (3rd) all day long. Obviously on the highway you won't get the optimum fuel mileage, but before transmissions were built with OD (4th) they were only ever 3-speeds (ie, TH350 & TH400).

 

True,before OD they were just 3 speed,but they didn't just "add" a gear.The gear ratios were diff.

 

You're right, 1st and 2nd gear ratios changed, but 3rd gear has always been, and is still 1 : 1 .