I've got a '01 4.6L w/ 193K. When driving up a hill/pulling trailer/etc, the trans downshifts from 4th to 3rd and engine rpm's exceed 3K, when all the instrumentation gauges spike, then drop to "home", then return to actual
/normal readings. The vehicle shudders for a second after the gauges return to thier actual readings after the vehicle rpm's return to about 2K. Also, all the instrumentation lights illuminate (airbag/check engine/etc.)

Any clues as to what's happening here? Again, only happens when vehicle is under load. The Check Engine light doesn't stay on, so I don't think there's a code to read, right? HELP!

 

take it to auto zone(or napa i think). they can check and see if its throwing a code.