Good Day! My brothers 2003 Jeep Grand Cherokee lost its trans on a trip from ME to MD.The unit was rebuilt by a reputable ATRA shop in CT.When he retrieved the Jeep today and started south all went very well with the exception of the fuel mileage,It is off by about 30%! This is a 4.7 HO with the (pseudo) 6 speed auto and never attained great gas mileage anyway (16-18 mpg at 60-80 mph in the worst traffic corridor in the US) but today the best he was getting was about 12-13 mpg and there were no excessive tie ups thru the GWB or the NJT. So my question is thisoes this seem normal for a freshly rebuilt unit?
I have had much experience with GM tranny rebuilds from Powerglides,all TH models and the 700R4 and never experienced this! Any Ideas? Thanks in advance! step66!

 

Could very well be our crap fuel. I'm pretty sure CT does the same thing MA does - put a sticker on the pump that says "10% ethanol", but in reality it's closer to 20% at many stations. Kills your mileage & performance. Makes them rich at our expense.

Either that, or they forgot to re-connect wiring for the torque converter lockup. You'd notice that pretty quickly on the highway though.