drive shaft moves
 

i have a 88 tll and when i drive easy it is fine but when i drive hard it maks a loud clunking noise tranny fluid is good diff fluid is good but when i was under there i played with the drive shaft in 1st gear and it moved about 3/4 of an inch and i dont know why please help

1: Bad U joints.
2. Broken rear diff mount.

on my 89 GTU i had the same clunking noise. does your car make your teeth rattle? mine felt like that and it turned out that my u-joint had died(which is somewhat common)i had to replace my driveshaft :(

the u joints are good and the diff is not moving the hole shart moves and the stops if any thing it might be some thing in the tranny or diff maybe

i would just go ahead and replace the drive shaft, but get and aftermarket one with interchangeable U joints considering the stock mazda ones dont. this will save tons of money in the long run.

where can i find a aftermarket one

Does the shaft move side to side, or does it slightly rotate? If it moves side to side, then that indicates bad U-joints. If it rotates slightly, that generally means a worn pinion/ring in the diff.

Aftermarket shafts are available from Mazdatrix, or any driveline shop.

I am throwing up the bullshit flag on the "non-replacable U-joints"

I was selling them all day long about a year ago and now have a 1-800 number people can call and order their own replacement OE u-joints for roughly $20 a piece

I would pull the driveshaft off the car and rotate the U-joints around in a 360 degree circle. Normally, the front U-joint goes bad on these cars and will make some noise and alot of vibration. Plus, it won't cost you anything but a couple hours of time (2 tops). If you end up with a bad U-joint, PM me and I will give you the number to call to order a new one.

Otherwise, I have no idea what is causing your problem. Maybe the pinion is sloppy in the differential or something....

^ It is a comon thing to clarify stacked joints as non replaceable. You can order replaceable ones but they are a bare to get out. There is a few threads on this. You can even search my name for it and come up with a post that has #'s you can call for them and price.

pittbulls - You said the front moves?? I would not normally say this off the bat to someone but check the tranny mounts. The reason I say I would not say that to someone is b/c I doubt you are lifting your tranny and half of the motors weight with your hands. But hey wiles you are down there check it anyhow.

thanks guys i will try the stuff you said and see what happans thanks again

Even when you rotate the driveshaft back and forth with the car in gear or with the parking break on there will be a little slop in the trans and diff. As you move the driveshaft back and forth, just pay close attention to the joints to make sure there is no slack in the joints. If they look ok, I would guess its the diff mount. The diff is probably pushing up under hard acceleration and hitting metal instead of its rubber mount. Just a guess...