1999 1500 laramie 2wd lost the drive shaft after the rear u-joint went bad. We replaced both u-joints and all seemed ok until it was driven about 50 miles. There was a loud pop and now it makes a loud whining sound only when in gear and moving. It sounds like the transmission is whining but there's no lack of power or shifting problems. To be honest, its hard to tell if the whining sound gets louder under acceleration because the exhaust is too loud and I could only hear the whining when I let off the gas. Am I looking at a new transmission or is there an easy fix? It never whined before the u-joint was replaced. I also did notice that a bit of fluid leaked out from where the front of the drive shaft yoke went in when he first lost it and was on an uphill incline. maybe a 1/4 pt.

 

I'd try putting the truck on a lift and run it in gear to determine if the noise is coming from the transmission or the rear axle.

 

Did you top the tranny fluid off?

 

also remove drive shaft and double check your ujoint repair. is it still tight and smooth; or is it loose, catchy, noisey, rough? a needle bearing might have fallen out of place.

 

my dad had two sayings. 1. check the cheapest and easiest thinks first. 2. check the last thing you did.