So I got my car yesterday from my long time mechanic. He replaced my old tranmission with a "rebuilt transmission". When I started the car everything worked fine, as soon as I put the gear in drive and stepped on the gas the transmission lagged so bad!!
I stepped on the gas and it sounded like the transmission wanted to pull but there was no power at all. It's sluggish like a turtle but it eventually pulls slowly. All other gears work fine and don't slip and reverse has good power.
Is there anything I could check for myself that might be wrong?? Also the O/D button isn't functioning. Could it be that it is missing a bit oil? I couldn't check since I got it late at night but any suggestions would help!! My mechanic said he doesn't want to deal with it so he's returning all my money back...kind of suspicious to me.