1986 nissan 300zx Rear end metal on metal noise

[eonblu]

my z has a problem I need help fast, when engaging drive or reverse, then push accelerator, I hear a metal on metal sound, car also has vibration at 1500rpms and smooths out around 2200rpms is the drive shaft shot or is it something else

[spiderwebfx]

Check your brake pads. If they're worn down, the little still clip will be rubbing on the rotor to tell you they are worn down.

[OriginalWheelman]

If the Z31 has a carrier bearing in the drive shaft I would check it. If it's a clunk look at your universal joints. If it's a grind, look at anything that spins. Does it happen in all gears or just at low speed?

[eonblu]

Thanks for the response, I took it in and they diagnosed the universal joints, it would only happen as I would start out, forward and backward, as long as I don't gun it. if I start out at idle speed it won't do it. If you have anything else feel free to comment. Thanx

[OriginalWheelman]

That sounds like universals. They are very strong solid X shaped pieces of metal. On the end of each part of the X, a cap is fit with roller bearings on the inside. This allows the x to spin within the cap. The drive shaft is split so that one side connects to one line of the X and the other side of drive shaft connects to the other line in the X. The caps are pressed into the drive shaft. It allows power to transfer through the X without the two parts being in the same alignment. When the U-joints get old, the bearings inside the caps often disintegrate and fall out. This leaves a gap and the clunk you hear is the X hitting the inside of the cap. It's a very simple fix and the parts are generally cheap.

[Dattebayo]

It's simple and cheap just as long a you don't have to remove the exhaust to get to said U-joint. Just FYI.

[eonblu]

I truly thank you for you expetrise, I get what u r saying thanx for all of your advice you guys are awesome!!