I figured everyone would get a kick out of the headline but here's the problem. I just bought a 97'. High miles on body. Less than 100K on a Ford Reman engine. I had a tranny service done on it and it runs and drives great. The problem I'm trying to pinpoint is this. When I start out from a dead stop it feels like something in the rear end is loose and stretching and then going back into place but only without the thumping, creaking, cracking etc,. that you would expect from U-joints and such. Without having any pics, I noticed that the rear leaf springs are missing both their front retaining clips that wrap around the springs to hold them in place. It also looks like the bottom leaf on both sides is off canter with the rest. My theory is that when I apply the gas, the torque is causing the read axle to rotate or move enough that the springs are sliding some direction a little bit then returning. I know it sounds like a long shot but so far the U-Joints seem solid, the yoke doesn't move or make noise and I still have good limited slip (I tested it on a dirt road and looked at the tracks left behind). The diff is full and has had the fluid changed. The guy said everything looks alright in there too. The strange thing is that it doesn't do this all the time. I have to look closer to also see if there's something cracked or broken. I had the thing up off the floor and all the leafs seem to be unbroken. Sometimes I can come to a stop and go again and there's no noise or loose feeling at all. Any opinions out there?

 

how far twisted are they? a very slight twist is not abnormal with out clips

It cost $10 to put those clips on to check your theory. Either way they are a good idea as they keep the leafs aligned and prevent a single leaf from inverting

 

They're not too bad. Maybe 1/2 to 3/4" twisted off center on the ends. I just can't think of anything else that would cause that problem. I found a place that sells aftermarket retainers that have the little pin on the bottom to hold them in place. They're only about $4-5 apiece. Small investment to try to solve a larger problem. I would say you have the right idea too.

 

my leafs are off too but i dont get the clunk you do... Although when i put my truck in gear i can get a CLUNK, also when its in park i can move it back and forth 6 inches before any action in the drive shaft. Put your truck in park, (don't set the brake) on flat ground and see if you can move it and get the results i did. it may not look wore down when you go take the diff cover off, but its due for a ring and pinion is my bet.

 

Thanks lariat 4.6. I will look into that too. My guessd is that it won't be anything simple.

 

I tried this and I could move it back and forth about 4-5 inches. Sounds like it's time for some new parts inside.

 

Just service it. Its wear. You can run it for awhile.

 

Sorry about the absence here. I had a dose of PMS (Post Marital Syndrome) going on. Anyway, I figured I would get another shop's opinion on the rear end gears just to be safe and I was told that they're fine. The mechanic told me that he believed the noise was coming from my slip yoke so I took it to Ford to do an oil change and to check it and they told me that I should have it greased. They did just that and a couple other minor repairs and recall fixes and that noise went away. I also replaced the missing two clips on my leafs and that sound/ feel went away. So far, no problems and GOD willing no more slip yoke noises. Thanks for all the input everyone. I appreciate the help.