There are a lot of factors that can affect gas mileage but I would think that is a bit on the low side. You did not mention if that was around town or highway mileage ? I would think that you should be getting a lot better highway mileage any way. I am comparing it to my 85 Blazer with 305 that will pretty regularly get over 20 mpg highway if driven at around 60 mph with the 700R4 in over drive. Around town I get about the same as you 13-16 mpg again depending on how many 5.0 Mustangs I try to out run at the lights ! One of my employees has an S-10 truck with a 4.3, I will try to remember to ask him in the AM what his does. It is fuel injected so it may not be a fair comparison.
Advanced Automotive Machine
I am geting that M.P.G. with a combo of side roads & Hwy.. I am not pushing it to hard (take off a little faster than most & 75 M.P.H. Hwy.). It's just that the old motor had the same M.P.G. and it was old & tired. I figured that the new motor would get better.
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