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Is there a difference in width between a 57-60 9" rear end and a 61-64. I used the info from a post in the 48-60 forum that lists usable axles for a bolt pattern swap. I got two driver side axles from a 77 and 78 Tbird. They are too short . I'm going to go ahead and narrow the housing 1" each side to get it right and also make my fat tires fit under the fenders. I just wanted to know if the info is correct or not. Also to put out a warning to others wanting to do this swap. Rich
57 thru 72 are the same width, but the drums & backing plates are not the same. so the difference can appear between the bearing and axle flange making certain years have greater track width and others less track width.
The variation in track width can be overcome by using the correct axles & drums & backing plates from the truck the replacement rear/housing is going into.
I don't believe the axles from a Dana or integral rear, like a 77-78 T-Bird are gonna fit a Hotchkiss style 9" FoMoCo rear end though.
Thanks for the info guys. Like I said I'm going to narrow it a bit anyway to fit wider tires and the tbird axles are just under an inch shorter so it should work out fine. Just wanted to let anybody else who was thinking about this supposed to be bolt on swap that it may not work so easy. Rich
Cobraguy, I think I see a kink in the line here. Your original post
Is there a difference in width between a 57-60 9" rear end and a 61-64.
If you add, Is there a difference in width between a 57-60 9" rear end and a 61-64
for the F series pickups, the answer is no, but the Ford 9" was offered in other vehicles that did have a different width.
I think you may be crossed up a bit on that issue.
John that was the question I was asking. I'm using the recepe I got from the 48-60 forum and it don't work. I did make one discovery though. I pulled my rear end apart and did some comparing last night. I found that the side gear in my trac lok is narrower on the driver side than the passenger side. The driver side axle does not reach the spline but the passenger side does. Just for fun I stuck an open pumpkin in and both sides reach the spline. The axles only engage 1/2"-3/4" of spline in this setup. So if anybody is using this setup be aware that the axles are enaging only halfway into the side gears of their differential. Under normal daily driver use this shouldn't be a problem but throw in some extra horsepower and a heavy foot or load it could become one real quick. Rich.
I have done this axle swap and it worked great. The truck is a 1955 with a 72 F100 9" rearend. It has been driven over 10,000 miles since then. I wonder what the difference is?
Rich, I havent read the reference that you point to, and I am wondering if the axles may have been replaced along the way. While the chunk is offset to the passenger side, the axles are the same length. When Ford increased the size of the rear brakes in 68, while using the same parts internal, this caused the axles to not engage the chunk as deeply as before.
Maybe Greg aka the truckfarmer has a little more info.
Guys I found the answer to my riddle. My trac loc has a 31 spline clutch hub in it with a 28 spline side gear. I guess I gotta check closer when I get those really good deals on parts at the swap meet. Oh well I was gonna rebuild it anyway.