Ford 8.8 Clutch Pack Minimum Thickness

[DuckRyder]

Any one have a Ford Document that gives a minimum thickness for a clutch pack? I'm finding videos than mention minimums in the workshop manual, but don't find anything in Alldata or TSBs.

It is a 2001 Ranger 8.8 Track Lock, Door Code R7 Axle Model S333W (at least I think thats what the tag says, someone undercoated it for all the good it did the housing...)

TIA

[jmlay]

I could not find a Ford document but I keep seeing these numbers in all of my searches.:

Ideally you want the entire clutch pack, including the shim, to be about .640 to .645 inch for a stock clutch pack and as thick as .655 inch for a performance pack (bottom).

https://www.diyford.com/ford-8-8-inch-traction-lok-differential-assembly-guide/

[DuckRyder]

Thanks Mike.

Preparing for a discussion with a recycled supplier so looking for something published.

They are neither one anywhere near even .640...

[Rory428]

Years ago, when I ran a 8.8 rearend with a factory traction Lok unit, we chose to install good used clutch packs, which allowed an extra friction disc per side, which provided a tighter package, but with more of a tendency for dragging/chattering around corners, but with greater holding capability. So good for performance duty, but not so much for normal street driving. I don`t recall what the package thickness was, but as long as it will physically fit together, in the carrier, more clutch discs provide more surface area, so better holding power.

[pbf777]

      The "stacking-height" of the clutch packs really isn't that critical, though reasonable is required, and the function doesn't change dramatically just based on this dimension value.  The O.E.M. designed it that way because this makes it easier in the manufacturing and assemble process and then the resultant dimension changes as the clutch pack wears in service.

      There is though the undesirable effect in the "side to pinion gear" relationship in that as the clutch-pack wears and experiences a loss in the stack-height, the gears move away from one another; this allowing the load conveyance path to move away from the root and climb the gear face towards the toe which results in a weaker setup and possible failures.  And this is probably the biggest consideration in setting the stack height so as to drive the "pattern" as low on the gear sets as possible, but without incurring binding lodging in rotation.   

      Also, when attempting to "add-a-plate" pay attention to where on the side-gear splines that the "extra" plate might ride, as often it is not well positioned for engagement.   

      Scott.