I just bought an SRT6 with 65K miles on it. It drives and runs well, but after it warms up it refuses to accelerate normally when I floor it, but very slowly gains speed. I have noted that it also is slow to shift out of 4th and into 5th, OR the torque converter is slow to disengage in 5th gear, one or the other.

Anyone have any thoughts? Needs a transmission filter and fluid change? (I have the right stuff on order.) OR could this be a fuel pump failure or other engine-related problem?

EDIT: One other factor; mechanic believes intercooler pump is failing. i plan to install a Johnson pump.