OK, this is the first problem I have had with my 98. Everything has been going great with it until the other night. I got in the truck after work, started it up and let it warm up for a bit. Drove out of the parking lot and got on the freeway where I accelerated up to 55MPH and noticed a vibration.

I promptly turned off the radio and air vent fan to better understand what this was. All I can offer is that it is a vibration/hum that is coming from what I believe to be the transmission area of the truck. I can further add that the noise only happens when the truck is in gear and rolling, usually when under a load. The faster I go, the worse the vibration/hum. Under 15 MPH it is unnoticeable.

Any ideas?

 

U-joint......................



also, i see you have a QC, check the carrier bearing

 

Mine did something similar and was the front drivers side hub bearing.

 

I will definitely look into both of those, but I might have missed stating that the vibration/noise goes away while rolling and I put the transmission in nuetral... Would that still cause you to be thinking carrier bearing or U-Joint?

 

yes, that actually makes it more likely a driveline problem.

 

Thanks Timmy! I am so glad I am not focusing on the transmission! I am trying to locate the part/source for the carrier bearing, figuring I will try that first before the U-Joint. Or, do you think I should go the other way?

Any options here for an upgrade/BOMB?

 

slide under the truck first, grab the driveshaft and give it tug and twist. you will be able to see the play in the carrier or the u-joints.

also, when carriers go they usually get hot! slide underneath after you just had it out on the road. carefull because they get real hot!