67LimeCoupe

Just bought a 84 GT with a 302 and a T5, PO claims to have 3.31 gears in a 8.8 rear in this car but I am doubtful as he said it was the stock rearend, and 8.8 wasnt available until 86... Anyway, whenever I back up while turning I can hear/feel the rear jerking/clunking, it feels similar to turning in a tight circle with a 4x4 truck. I know that I need new shocks in the rear, assuming there are other worn suspension bits back there would that cause it? Or is it most likely the rearend ( I will identify it and update this thread once Im home). I also notice it when turning at low speeds while in 1st.

If its my U-joints, whats the best way to check these?

Urambo Tauro

Jack it up; get the wheels off the ground and put the transmission in neutral. Mark the tire and the driveshaft or pinion with chalk or something.

Turn the driveshaft back and forth to check for play. If the u-joints are the greasable type, check for play before applying any grease. Rotate and compare the number of driveshaft revolutions to the number of wheel revolutions and do the math to find your gear ratio.

88 orangepeel notch

Sounds like someone put a spool in the rearend if it was an open differential. Or they shimmed the clutch packs way on the tight side if it's a posi. If I'm understanding your description.

And when checking u-joints, just look for any play or slop in the joint. Any at all and it's bad. Check with no load on driveshaft. Car safely jacked up on stands.

67LimeCoupe

So I guess I have SOME good news, if you can call it that. driveshaft to diff flange allen head bolts were not even finger tight, I added loctite and torqued them down, this solved most of the clunk and eliminated the vibration at speed on the highway.

I still hear some noise but it sounds more liked worn rubber bushings moving around when I turn.

U joint looks good, although with the car in first and the rear wheels off the ground there is a bit of "slop" before the driveshaft will turn the wheels, is this simply due to lower looser tolerances ford allowed back then?

Here is a picture of the rearend is this an 8.8?

dawson1112

lol gotta love those second hand projects. I bought a car one time it was missing 3 of those bolts, and the 4th was so tight I had to use a breaker bar with a short pipe to get it loose. I guess they thought 1 would be enough if they put 85 ft lbs of torque on it lol

67LimeCoupe

Waiting for the day that I see someone post one held on by zipties and duct tape, its only a matter of time!

Boss_Hotrod

Yep gotta love someones else's projects. But yeah, that's not an 8.8. Its the 7.5.