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Max tire size for a Ford 8.8 rear axle???

atomicjoe23

Well-Known Member
What is the max tire size you would recommend running on a Ford 8.8 axle. . .let's say two scenario's:

Scenario 1: stock 8.8 from a '96 Ford Bronco

What is the weak point in the 8.8. . .i.e. what will break first from using large tires?

Scenario 2: upgraded 8.8 to remedy the weak point above.

Thanks!
 

Ryabac18

Member
What gearing do you want to run? example 4.11, 4.55 etc thats a big factor. The bigger tire you are going to run the slower the acceleration so you have to factor in for that.
 

isdtbower

Well-Known Member
Vehicle use and weight and HP?? They have survived in some lite weight sand buggies with reasopnable paddles, but not much offroad or sand with weight.
 

atomicjoe23

Well-Known Member
1996 Ford Bronco. . .stock 5.8 engine; haven't thought about the gearing yet. . .figuring out gearing will happen after determining tire size so the two are complimentary.
 

isdtbower

Well-Known Member
If you are thinking KOH like your other posts, a 8.8 won't work for any of it. Minimum is probably a 9" and built to accept 37-40" depending on class. $16k+ axles are not unusual. A $40K rig was a good number for the first couple years. Now, I doubt that is good for any competitive/finishing rig in any class.
 

atomicjoe23

Well-Known Member
isdtbower I won't be running in a KOH event ANY time soon, but with the '49 Willy's pick-up body I think that is the build direction I will be going. . .

. . .I've flip flopped about solid axle conversions back and forth so many times it's not even funny; wondering if it woudl be better to swap the D44HD front (Dana 60 would be better I know, but I don't have one right now)/GM 14-bolt rear that are under it now onto the Bronco chassis or keep the D44 TTB and go with a Ford 9' (like a TTB Ultra 4 car instead of A-arms). . .

. . .I think I need to get the body swap done first and foremost just so I can actually enjoy driving the thing for a little while before I sideline the project for even longer. After I get to enjoy the truck for a while I will upgrade the rear axle to a Ford 9" at the very least. . .what I ultimately do with the front end will determin what rear axle I end up going with.
 

Josh 8

Well-Known Member
8.8 are notoriously weak. I have blow the spiders gears out of one in a bronco doing some "mild" prerunning. swapped to a 9" out of an old pick up with 28 spline axels and it was way stronger. This axle had the old Edsel housing. Total junk yard find. I even preran the b1k with this axle setup once years ago. Of course I took it easy on it on it and ran about the same pace as i did with the 8.8 and it always got me back.

A few years back I built up a real 9" rear end using grand national parts from speedway engineering.

Any way, when I blew the 8.8 up it was a basically stock bronco with 35" tires and 3.55 gears. The spiders made holes in the back cover. They cant take any shock load.
 
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jon coleman

Well-Known Member
What is the max tire size you would recommend running on a Ford 8.8 axle. . .let's say two scenario's:

Scenario 1: stock 8.8 from a '96 Ford Bronco

What is the weak point in the 8.8. . .i.e. what will break first from using large tires?

Scenario 2: upgraded 8.8 to remedy the weak point above.

Thanks!
ran one in stone stock, 35×12.50. not properly truss'd, 4.56 c6, ford gt 40 crate 400hp. ran perfect at parker but ate a r& p.stole one out of chase bronco & finished.bronco made it home fwd.still not truss quite right and didnt check axels 31spl after parker and broke axle at san felipe, then after driver swap, ( fixed first axl), second broke.in the nasty wash.dnf.8.8 set up right can work decent.its all in right foot & what part of earth u hit....
 

jon coleman

Well-Known Member
ran one in stone stock, 35×12.50. not properly truss'd, 4.56 c6, ford gt 40 crate 400hp. ran perfect at parker but ate a r& p.stole one out of chase bronco & finished.bronco made it home fwd.still not truss quite right and didnt check axels 31spl after parker and broke axle at san felipe, then after driver swap, ( fixed first axl), second broke.in the nasty wash.dnf.8.8 set up right can work decent.its all in right foot & what part of earth u hit....
junkyard hot find e ford van ,9", 31 spline, wider, big bearing& i believe big bearing housing, can go 35 spline max before after market housing
 

Travisfab

Well-Known Member
The weak point (externally) is where the axle tubes slide into the cast center section.. Weld the tubes and more importantly, add the truss from Desolate. Internally, you have c clips to deal with, 31 spline axles, and the factory limited slips seem to just be ok. With a truss, and 35" or smaller tires, I would be totally comfortable in a mild prerunner.
 

jon coleman

Well-Known Member
The weak point (externally) is where the axle tubes slide into the cast center section.. Weld the tubes and more importantly, add the truss from Desolate. Internally, you have c clips to deal with, 31 spline axles, and the factory limited slips seem to just be ok. With a truss, and 35" or smaller tires, I would be totally comfortable in a mild prerunner.
also sleeve inside of axle tubes w- cro mo into center cast , roset weld in place, tie outer into big bearing cups and Ditch c clips!!!!!, they are outlawed here!!!!
 
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