please help with a noise i can hear.

[dan1989]

hey i recently bought a 75 beddy cf. i have noticed a sound which seems to be coming from the rear of the car - perhaps the wheels. i hear the sound when i need to hit the gas to maintain a speed of roughly over 65km p/h. if i am traveling at arund 70km p/h and dont hit the gas i dont hear the sound but i obviously start to slow down. then if i hit the gas to maintain the speed i can hear the sound. please and help on what it may be and is it and easy and or cheap fix?? thanks all

[Numnutz]

put the van in neutral when you can hear the noise, if you can still hear the noise, most likely the diff gears are worn and may be close to failing. 

[Warren]

What sort of sound ?

Things it could be.

exhaust 

Wheel Bearings
Diff bearings
Diff backlash
Universal Joints
Gearbox bearings

The Passanger screaming

Park the van, put the hand brake on, gut down on the ground and try to twist the tailshaft there sould be very little twisting, if there is try twisting back and forth the tail shaft while holding the yoke (one at a time) at each end of the tailshaft if there is any movement replace the uni.

If no movement then look at the backlash in the diff - do the same twisting motion to the tailshaft and see how much the yoke on the diff moves, a degree or two is OK any more can indicate a worn crown wheel and pinion.

Wheel bearings on the way out usually whine in a constant way increasing in pitch/noise as you go faster.

If your unsure allways replace the cheapest bit first ie uni joints before diff etc

I would hazard a guess and say the uni between the tailshaft & diff though.

Warren 

[Worzel]

If you have just bought it then you want to go over everything and get to know it.
Everything that you haven't checked is suspect
I would replace the unis and put a strap under the front end of the driveshaft, this one is just 30x3 steel.
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