what is that noise

[bigchris2005]

ok i have a 96 fullsize bronco with a 302. when i am driving it down the road i hear a load humming/buzzing noise (almost sounds like jumbo mudders running on the pavement) when i hold the down then i can let off of it and i goes away what is the problem here i am at a lost. it does this at all speeds over 20 mph but gets louder and louder as you are increasing your speed but as soon as you let off of it it goes away.

so here is what i want to know

has anyone had this problem before

if so what was it

and where should i start first

 

[Seabronc]

It is sort of hard to diagnose from here, do you have an idea were it is coming from, ie. front, rear, under the truck, etc.?

Good luck,

>-

 

[nelbur]

A whine that increases in frequency with speed, and stops when you let off the accelerator, is the classic symptom of a noisy rear end (worn ring and pinion). Make sure you have oil in the rear end. A thicker oil may reduce the noise somewhat. Mine makes the most noise around 35 mph, but that may just be the frequency these old ears hear best.