10.5 Posi Spring Question

DART505

DART505

WFO ALL THE TIME
Joined
Jun 1, 2006
Messages
1,198
I have a new posi the heavy duty 3 or 4 pinion I forgot what I was told.The problem is it not aggressive & have 1 wheel spin sometimes.I shimed the spring that applies the clutches & now it hooks up so much it pops loud during corners.I tried 2 extra bottles of friction modifier with no luck.I remember seeing something about the Lightning had a stronger spring but need a part # & want to know if they innerchange in all the clutch posis?
Thanks!
Chris
 
I read on another forum that if you put less friction modifier in, it will actually make the limited slip more aggressive. Try 4oz first and add more if it is to aggressive on corners. I plan on trying this when I replace my diff fluid...my LS sucks!!!
 
modifier won't help you have to go back in and make your shim a little smaller it's the only thing that will fix it.
 
I was told to restack the clutch pack metal, clutch, metal, clutch, since the factory makes them soft for gramps and grannies.
 
The first steel you put in is a spacer you can shim this in or out to set how fast it engages. any time some one comes to the dealer with the posi (noise, jurking, grandpa stuff) my buddy at Ford puts in the smallest shim so it won't engage. He redid mine to make it hit faster. hits fast no popping. I can pick his brain if you need more info.
 
I tried to find some info on making the factory l/s unit work better but I found very little other than restacking the clutck pack and using the belleville washer out of a Lightning truck which will give more preload to the clutches.

The best soulution is to upgrade to a unit that actually works as it was intended to do.

FWIW I will have a factory l/s unit with a new in box rebuild kit for sale very soon.
 
i think i saw you "over there" too..

now this bellville washer...is that for a 9.75?... will it fit a 10.25-.5 ?

and does stacking metal/friction/metal require more parts to be bought?..more friction?..and is it hard to do?

i can have my dealer do this on a complaint, to take care of me till my Detroit gets here in a few years.

and main bearings go untouched with this right?...axles and spiders only
 
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This is all the info I have.
http://www.alldieselmotorsports.com/forum/showthread.php?t=1349

MachinistOne said:
Basically with the 3-pinion posi, you can split the case and remove all the parts, keeping them where you can put everything back in the same place. Soak the clutches and plates for an hour in 90-140W synthetic. Then stack the clutches and plates until they are all used up, now the bevelle washer is the key to pre-load. My posi has a belvelle washer from a lightning truck in it, it has more lb/in pre-load. you need to make it so that when the assembly is bolted back together that you can insert a .015" feeler guage in-between the belvelle washer and the first shim. Basically get it as tight as possible without flattening it. Then when you set up the diff, only use 2oz of the friction modifier, add a little more if you get chatter.
Click to expand...
 
When I get it going again I will have to redo it.It is awful,at least with a spool it would not pop.:pop:
 
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