I have an 87 that was did a lot of sitting in the garage while I worked on it (in between the honeydo lists and repairs to our other vehicles), recently I got it to the point I can do my long missed weekend rides but noticed that when I slowly back up and sometimes in the corners notice a binding taking place (I can see the tire actually slightly bump as I hear the clunk or what I would call binding sound). I jacked the car up and checked all the u-joints and spun the tires both ways and hear not a thing, everything is tight. any ideas on where to start on this one?

 

Try changing the diff oil and make sure the oil you have has the LSD additive, or add some along with the oil. It sounds like the diff is binding. Check your U-Joints while you're under there too.

 

When jacked up you should turn the tire back and forth and watch the axle and U joints. The axle and U joints must rotate and reverse exactly like the wheel does, any lost motion when reversing the wheel direction is a sign of either defective U joints or the wheel bearing. Also put your hands at 9 and 3 and try to wiggle the wheel, do it at 12 and 6, there should be very small movement. Wheel bearing make a grinding grating noise, U joints make a squaking noise and at a rate about twice the wheel rpm. You have a bad wheel bearing if the wheel rotates some degrees before the axle rotates and you see the outer U joint and axle move together. You have a bad U joint when you see one U joint yoke turn some degrees before the other yoke turns.

Clunking noise is usually due to excessive ring gear to pinion gear clearance (U joints also make clunking noise) and you can see this by lifting one wheel and rotate the wheel back and forth and watch the drive shaft. A little lost motion seen in the driveshaft moving back and forth is normal, but not a lot of lost motion. turn the driveshaft back and forth and see how much play there is, a very little is normal, but not a lot.

 

thanks for the help, much appreciated.