Ford-a-tude

Yes it will do it in reverse. I was trying a few things last night and found that with only one tire on, dosen't matter which side, it does not do it. If I decide to break into the diff case again I'll check the pinion bearing to be sure.

Ford-a-tude

I am not going to call this solved yet, but I think I am finally on the right path.

I realized that I had a "DUH" moment while messing with the pinion angle. I had the front on ramps but the rear was on stands that were on the frame. That meant the suspension was at full droop when I set the angle. DUH, I knew this already. So last night I put the stands under the rear axle and did it with a loaded suspension. MAJOR reduction in banging and rebounding! It will still do it a little bit, but I have to be doing something stupid to get it to happen now. During normal driving it is hardly noticeable. I will see if I can dial it in even better next time I get it on a lift.

moosestang

Sounds like clutch chatter to me. How many miles on the spec 3+? Have you changed the stock clutch line to a stainless steel braided line? Believe it or not, changing the clutch line really helped make my spec 3+ more street friendly.

Ford-a-tude

I did the clutch last summer, so only several thousand miles on it since then. I am not ruling anything out at this point, but fixing the pinion angle has actually lessened it. Not sure if there is some kind of interaction between clutch chatter and pinion angle though.

Simon1

If fixing the pinion angle helped it then I would guess it was the differential. It was my first guess too. But clutch was my second guess.

Where is the noise coming from?

They make a mechanics stethoscope you can use to listen for the noise.

Simon1

If it's the rear end, take it to a pro.

808muscle

Cause if its out of whack it will get worse and posssibly grenade the entire rear end. My PA was out which gave me lots of vibration but nothing like the noise you have. Thats something way more involved than just your PA.

Ford-a-tude

That is the deceiving part, from the drivers seat you would swear it's the rear end. From outside the vehicle it sounds more like in the middle and when I am under the car with my ear against the drivetrain, it is loudest right where the transmission connects to the driveshaft. I just had the driveshaft out and there is no play in any of the U-joints. I also checked the output flange of the trans and the pinion yoke of the rear end, both are rock solid with zero play in any direction. I'm stumped.

Joecls

Just drive it until it breaks lol

Simon1

You need to take the cover off and look, and I would also disconnect the DS from the rear end and spin it by itself.

I had a detroit locker in my car and one day I got a strange clicking sound that was just like you described. Then, a light howl from the diff. I took it to the shop and only one bolt was left in the ring gear, there was one broken spring in the diff and because of the broken pieces, it had made a few holes in the diff out of round. Instead of repairing, I replaced it. Everything except the axles were replaced. I now have a Auburn gear driven LSD.

The only way to really know is to pull the cover. You probably will have to pull the panhard bar and buy a little bit of RTV or whatever is used to seal the rear end up.

Again, take it to a pro. I don't mess with rear ends.