3500 Vibration and hum

DuraVette · 11-05-2009, 04:46 PM

Just traded 2500lmm for a 3500lmm and noticed that between 1700-2000rpm there is a slight vibration coming from what feels like the front of the motor that i didnt feel in the other truck. the only difference motor wise between the two is dual alternators on the 3500. Any thing i should look for?

DuraVette · 11-08-2009, 04:59 PM

NO ideas from anyone? Some more information worse at 55-60 and only when pulling my gooseneck when acclerating. at cruise at 55-60 cant hear or feel. I doesnt feel like an out of balance wheel. im stumped.

**Johnasara** · 11-08-2009, 05:05 PM

How many miles are on it???? You could just have a problem with a U-joint or possibly the drive shaft is out of balance. That is about all I can think of.

DuraVette · 11-08-2009, 10:54 PM

sorry forgot about mileage, truck has 36k miles. could u-joints or driveshaft cause vibration in front end?

**Johnasara** · 11-09-2009, 05:21 AM

Is it a 4X4???? I was just throwing out ideas of problems that come with a certain speed. It could be tires too.

DuraVette · 11-14-2009, 05:10 AM

its getting worse can hear a hum at all times louder when accelerating. sounds like cooling fan is slightly engaged. how easily should it spin with the engine off?

**Johnasara** · 11-14-2009, 06:01 AM

They have a clutch so you can spin them with the engine off. It sounds like your fan clutch may be bad or out of round.