Hey folks! I bought a 2004 F-150 that had 12k miles. It has been driven around 100 miles per year for the last 2 or 3 years.

I am hearing a loud whinning noise coming from behind. This happens when only when turning under acceleration. I am thinking of changing the rear end fluid. Any thoughts?

 

That would be a good place to start.

 

I went with Motorcraft 75w-140 and the XL-3 friction modifier and the noise has gone away.