So I have a 97xj inline six I just dropped a new engine (3000 miles Ago) a new cat and O2 sensor and just did my transmission services (flush both torque converter and new fluid) Anyways if I'm driving down the hwy I have to get it over 3000rpm to get it to go over 75mph and I have to keep it at 2700 just to keep it at or above 75 now this wasn't happening before the new engine, now I know yall would say "take it to the people that did the engine" but I have and they don't think there is anything wrong with it. This problem has beat me, any of yall have any ideas? Thanks for the help

 

Is the transmission fluid at the correct level?

 

Yeah everything is good fluid wise

 

Could it be the transmission slipping?
Flushing the AW4 transmission can cause problems. It is recommended to not do it.

 

It was happening before the trans draing and it's not slipping it's just having a hard time at high speeds