How can you identify the FAT halfshafts?

MTTod

Registered User
From what I've dug up here the fat shafts came on the 5 speed cars. Does anyone know the diameter of the fat shafts? Also, are the CV joints different or just the shaft itself?
 
Actually I think the fat shafts were stock on all the SC's. I think they were just put on the drivers side only. Well to describe it easily, they are fatter. Sorry can't tell you diameter of shafts but it is a noticeable difference. Problem is that the shaft isn't what goes when you snap them.
 
Mine had the fatter shaft on the passenger side, it is noticablly bigger. Like Aaron said the part that breaks is the other side of the CV joint. Failure may be because of stress fracture and or bearing failure. I just put 2 brand new halfshafts and rebuilt all the bearings in the carrier. If it breaks now I will have to try another route.
Gary
 
Here is a pic of a Raxles and a Ford fatshaft:

rxvsfs.jpg


The regular shafts do not neck down where they enter the boot, since the whole shaft is the same diameter.

If you are looking for more strength from the Fat shafts, you may be barking up the wrong tree. They are not stronger where it matters and were originally installed from the factory to help dampen vibrations and potentially guard against wheelhop.

The Raxles are really strong, but curently are not being produced. Good news is that very few have broken half-shafts on these cars.
 
Actually I think the fat shafts were stock on all the SC's

From what I've been able to gather on the factory supplied fat shafts, they were only installed on the righthand side of the 5 speeds. The shaft is larger, but the CV joint and splines are the same as the left side or those that come in automatics. The reason they are fatter is not for added strength, it's for added mass to reduce wheel hop.

Now that Raxles is no longer able to supply fat shafts with larger CV joints, we are pretty much stuck with the stock shafts unless we go to a larger spline like the Cobra uses. I'm hoping something is offered soon, because I believe the halfshafts are now the weakest link in my drivetrain.

At the SC/XR7 Shootout later this month I'll be racing with real slicks for the first time and keeping my fingers crossed that the stock halfshafts hold up.

David
 
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At least the 89 autos got the passenger side fatshaft. Mine had one from the factory. I'm not sure which year they stopped putting it on the autos. Probably was there 89 and 90 on the autos.
 
I didn't figure the shaft itself would be the problem, the CV would be the weak point. Since they're the same guess it doesn't make a difference.
 
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