Any 8.8 gurus around ? Basically my question involves the interchanging of spider gears between open and L/S diffs.
My truck has a 3:08 open. OK on the highway but kinda sucks around town.
I've got a 3:55 posi, kinda high miles but the ring and pinion look ok. Pulling it apart though, I found a couple chunks missing out of a couple of the spider gears.
I was going to order new spider gears when I order clutches for it, but I just ended up with a really low mileage 3:55 open.
I was told today that the spider gears out of that open diff will fit the posi carrier. That would save me a few bucks if they will indeed work.
Anybody know about this ? 8.8 interchangability isn't my strong suit, so I'd appreciate some opinions.

 

eBay search Ford 8.8 Spider lists gears and in descriptions it says "open" or "posi" on listings so I would say non interchangeable.

 

Not sure of your budget but check out American Axle Manufacturing. The sell a helical style posi unit for reasonable price. They modify a stock posi casing for the unit, that's why it's priced decent. I have two F150's both 2wd, one is LS factory style and the other Helical. The Helical walks all over the LS off-road and in snow, it uses a 3 to 1 side to side ratio when wheels slip so it's like having traction control only with full power. Easy to stay straight when slipping, no slide out.
AAM is an original equipment vendor for Dodge and others so it's high quality.