04 Chevy Colorado Vibration

A friend of mine has an '04 Chevy Colorado 3.5L 5 cylinder 5 speed 4x4 with 185k miles.

He is getting a fairly mild vibration that you can feel through the gas pedal and floor boards. It doesn't sound very loud at all but it is noticeable to the ear.

It is intermittent and not constant. It happens while in gear but coasting down hill the most often. It happens at speeds above 50-55 mph while in gear, in neutral, clutch in or clutch out, and at any engine rpm while in 2wd tc mode.

Any ideas? I was thinking maybe just putting some new diff, tc, and tranny fluids may help out.

 

Sounds like its a driveline or carrier bearing issue. Especially if you can feel it in the pedal. Also deceleration is the dead give away

 

the carrier bearing was one of my initial thoughts too but I don't know if he has one. It is an extended cab. I know double cabs have them but do extended cabs also have them?

my taco being a single cab and not having one i've never paid much attention to others issues with a carrier problem.