On my son's truck, it doesn't seem to rev up much at full throttle. It always shifts at 4,000 RPM's too, so is that the right range?

I've removed the throttle body and thoroughly cleaned it, ran warm water through the vacumn port and added a K&N filter with a larger MAF. I've checked to make sure the pedal pulls the throttle blade fully open so I'm wondering if there's anything else I can do.

Great site - you've always had great advice and you are an impressive resource when working on or trucks!

Thanks,

Hondo21