Just wanted to get some input regarding my ford 8 inch rearend in my 64 Falcon. It's a posi with 3.25 gears. My car has sat for a couple of years and has been on jack stands raised in the garage due to the flooding we suffer from occasionally here in Houston. Didn't want to get caught off guard, if you live here you know that with thunderstorms you just don't know what you're going to get and I couldn't take the chance that I would be at work and something like that should happen. With that being said the last time I drove the car all was fine, didn't beat up on it or anything like that. It was basically driven around the block a few times trying to sort out an issue with the carb popping and fouling the plugs. So I parked it and left it as such. Well the itch came back to get it on the road again and I started to pull the motor over the winter. So today I pushed it outside to make it face the garage door in a effort to pull the block and when I was pushing it around by myself I could hear a knocking in the case. You can actually see a slight wobble as it moves but I was doing this by myself by hand so it was kind of hard to diagnose it and move it around at the same time but it appears to be coming from the rear. Any ideas what would cause this? All was well when parked and now all of a sudden it now has the knock? Does anyone think maybe that an axle may have become unlocked from it's position? I am going to finish the engine build but in the coming months I will move onto the rear and I am just trying to figure things out. Thanks in advance, Mark
Knock knock. Who's there? 8 Inch. 8 Inch Who? 8 Inch ya glad I done responded to yer thread? Knocking or clicking? My Olds posi clicks after sitting all winter, A buddy suggested doing some figure 8's to distribute the lube and he was right, mine goes away after doing so. Not very scientific I admit but it works every spring. I also added a bit more posi additive last year, this year it was was just fine.
Yuppers, if if the posi has a clutch pack, I'd have to belive that Billy nailed it. Dry clutches in the posi.
Tell everyone it has a Detroit locker... Seriously though, dry clutch pack, mine does this as well. And I use posi additive.
I changed the oil in my posi 2 years ago and added a friction modifier. It is essentially pretty quiet aside from sharp turns while moving slow. I agree on the clutch discs being dry.
I don't know the type of "posi" you have in your 8" but I have a "posi" in a GM G-body (factory posi and gears) and am aware of the need for a posi lube. That being said, outta the blue one day, (as I am backing into a parking spot for an uncles funeral actually) the rear end suddenly starts making a racket ... it never did before this and I had owned the car for years at that point (as a daily driver). I recognized the noises as being posi related so the first thing I did was drain the rear and put in fresh oil/lube, some posi additive and the noise was gone. The only thing I can think of is, somehow the original posi lube wore out/failed and needed to be replaced. It may be (based on my experience described above) that you just need to do an oil/lube change. My posi uses clutch plates, I don't know what yours has or requires as far as lubricants.
Yup its dry clutches in the Trac Loc. If you haven't done it in a long time, change the grease in the rear and add limited slip additive. I always use 2 bottle of Mopar Brand Limited slip lube, just my preferred type. Yes you might only need one, but I never heard of Posi clutches burning up from too much limited slip lube, but I have from not enough.
Also once you change the oil, gently take it to a open parking lot, and do figure 8s slowly with the car for 10 or 15 min to get the lube with additive really worked in the clutches, it makes a huge difference.
i had an 8'' in my 37 ford years ago and the ring gear bolts stated backing out. Luckily i caught it before something happened.
If both tires are aired up the same and you are moving in a straight line I don't know if it as the posi unit.
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