I have a 1996 Discovery that runs and drives fine but makes a roaring noise when I let off the gas pedal. Does anyone have any ideas what this could be?

 

Probably your fan/fan clutch. I don't know the severity, but I don't think it's anything to worry about.

 

I don't know but the noise is pretty loud. It almost sounds l.ike a jake brake on a big truck

 

Check your rotoflex on the rear driveshaft, look for cracks/tears, etc. . Mine was doing the same thing. Buy the OEM disc, $60, aftermarkets do not last that long. Almost positive that is it. You can remove the rear shaft, lock the CDL and test. Might as well redo the ujoint while you have it off.

 

I thought that might be it. I checked my local autozone and advance auto parts and they did not show that part, where is a good place for parts?

 

For that you want to either get it at the dealer or at www.atlanticbritish.com

It is called a roto flex also known as a flex coupler.

 

If the roto flex looks good, and even if it doesn't, check the oil level on the transfer case. If it gets low it makes a roaring sound under deaceleration.