Have a 62 f100 with 31 spline rear. Wanting to change the axle to 4.5" lug pattern. Car is at the spray painters right now so I can't pull the axle to check. From memory (factory) 61-66 f100 9" rears are 61" That would make each shaft 29 15/16"? That sound about right?
I don't think so. I had 2 of those and I remember left and right being different lengths. Seems like 3.5-4 inches different from side to side. Good luck, Mike.
Really? I thought F100's had offset pinions so therefore equal axle lengths? I really need the thing to have a look at now!
This is a really good link on measuring your shafts: http://www.jalopyjournal.com/forum/showthread.php?t=255093 If you have a centered housing, yes. Of course from the factory they are off-set.
If they are not gonna be hooking a set of 13.5, or so, M/T's to the ground, I'd just do this to the stock axles, too. Hell...I even saw a thread, I think, about clocking them, and doing it yourself on here once...( ? ) My '58 9" had 31 spline axles, in my F-100, non-centered pinion. I hear lots of racers, however, are now going TO the lrg. ( early Ford ) bolt pattern, no? Damn hard to find a Cragar or Torque Thrust for 'em, though...
I read over on the Ford truck enthusiast board, that the short(right?) axle out of '77-'79 torino/t-bird/cougar is the right length for '57-'72 ford truck 28 spline 9". You just use the truck bearing/retainer plate. I was going to try this in my last '56 F100 that had a '57 F100 9", but is hard enough to find 1 of those cars in the junkyard, that they're willing to sell just the axle shaft, much less 2. I just kept the 5.5" pattern.
The brake offset between the two different years of axles will most likely be different. The T-Bird/Torino brake offset is 2 3/8" and the early F-100 brake offset is 2-2 1/4" depending on the year.
I believe the guy doing the swap was using '67-'72 era backing plates that worked with the t-bird drums.
Pull them and measure them, or you are sure to be adding a fail post to this thread. Guessing at this would be the equivalent of betting on black at roulette. Do you feel lucky?
Yep, I was trying to avoid pulling them, but sounds like it the only way to go. Thanks for the replies guys, I'm in Australia and redrilling the axles in not legal unfortunatly. I don't know how guys go using multi pattern axles, but re drilling what I have will fail inspection