Powerboost has different tranny, well not different but extra parts...sounds expensive to me if it has any issues. It does hall ass, had one when the replaced my back glass motor and glass under warranty as well.Any thoughts on the 3.5 vs the Powerboost? I don't really want the powerboost I don't think.
With all the warranty claims I have had on my truck I have gotten to drive all flavors of F150...3.5 is nice, too many moving parts for me..5.0 with the tow package was my favorite.
To answer the OPs question...Hell no, unless you can verify the transmission has been replaced.
My '21 has 98k on the motor and 38k on the replaced transmission.
