I recently purchased a '38 Pontiac with a Ford 9" rear installed and I'm having difficulty identifying it. I've seen numerous posts with tables listing years, models, and widths but nothing seems to match up with mine. There appears to be a lot of confusion over housing width and overall axle width (wheel mounting surface to wheel mounting surface). Well, at least there is on my part... Its not clear if the dimensions listed are the housing widths or axle widths. My axle housing has the dimples and a level plug (not a drain plug). The tubes are 3-1/4" with flat tops and step down to 3" at the flanges. The overall axle width is very easy to measure and is 63". The housing width is more difficult to measure with the brakes installed but I estimate it to be roughly 57-1/2". The wheel bolt pattern was originally 5x4-1/2". The axle ends have a small circular hole in the center with two other circular holes in line. The housing has small bearing flanges and is setup for leaf springs on roughly 45-1/4" centers. It does not look to be modified in any way. It is not possible to put a socket on the 6 & 7 o'clock center section nuts so it must be a 9". The center section has a single vertical spline and no drain hole. There is no tag present. It tests to be roughly a 3:1 ratio. According to the tables I've seen (which appears to be the same information in many locations): - The dimples and level plug indicate it is from '60-'67. - The 3-1/4 tubes with flat tops indicate a Ranchero or Torino. - 63" width indicates '70-'79 Ranchero or '72-79 full size. As you can see, the dimples and level plug contradict the width. Am I mis-intrepreting the width in the tables? Does anyone have any further information to help me understand what vehicle this rear came out of?
looks 70s to me....the 60s rears had but welded tubes, they were not lap welded to the center part of the housing. Although I don't know what year they changed. What exactly do you need to know about it, which makes ID so important? Besides curiosity?
Since its missing the tag, sounds like someone has removed the differential at some point in time and maybe they installed one with a different gear ratio.
I can't help other than advise to take the internet axle width tables with a heavy dose of skepticism. They often have contradictory information within the same chart.
I doubt that it's 'out' of any specific car. You're ***uming it's a unmodified rear which I strongly doubt. By 1960, Ford built very few that narrow so yours has likely been narrowed from it's original width. The only 9" that narrow in that time frame would have been the '59 Ford (the '57-58 housing had a drain plug), '63-65 HiPo 289 Fairlane or the '65-66 GT350 Shelby Mustangs, neither of the latter two being very common and the Mustang used big bearings. The small-bearing ends limits it to cars; no Rancheros or full-size wagons. Also keep in mind that 8" and small-bearing 9" 28 spline axles directly interchange, so a 'budget narrow' could consist of a narrowed 9" housing with off-t******lf 8" axles out of a Fairlane/Mustang/Comet to get the desired width. Most were narrowed at the very ends, so depending on how the individual did it it can be impossible to tell if it's modified. The pumpkin looks like a typical mid-'60s-'70 'standard' unit, you could narrow that down somewhat by pulling it and looking for a casting number inside.
I guess it's mostly curiosity. I just bought the car and I'm going through it trying to understand what I've got and then decide what I'm going to do with it. Its also my first experience with a Ford 9".
That's interesting because the posts containing the tables listing the widths made this seem like a wide axle, unless the tables incorrectly state the housing widths as opposed to the overall axle width, which would agree with your response. The build on this car appears to have started in the '60's-'70's. Its got a 62 Chevy I6 with a cast iron powerglide so the Fairlane/Mustang rears do seem possible, ...with the exception of the small bearings...
What size brakes does it have on it? That sometimes helps narrow things down. I've got a Torino rearend but it's buried under some snow right now so I can't check it.
AFAIK, most all the charts give the axle housing width, not wheel flange-to-wheel flange. There is also two axle offsets, depending on which brakes were fitted, so for a given housing you could have different overall widths. 11" brakes on a small-bearing housing is a bit rare, most were 10", but somebody could have checked the 'HD brakes' box on the order form too. Or somebody did some mixing and matching. There's also three car center hub diameters. '49-67 were all the same, in '68 Ford bumped it up about 1/8", then in about '70 they bumped the full-size car hub up some more so the older wheels won't fit the newer axles/front hubs. This is important when buying brake drums for correct drum register on the axle, and may give a clue as to the axle year. I don't recall the different sizes off the top of my head, some research should turn that up. Again, if parts have been swapped it may not tell you much.
Here is a chart showing various Ford rear ends. Yes, it is hard to read but it gives you some idea where it came from. Good luck!!
That's great information Steve. Thank you! I'll check the hub diameters. The hubs were actually re-drilled to 5x5 so the original Pontiac wheels both the front and rear.
This appears to be the same data I see all over the web. Are these housing widths or overall axle widths?
I say that chart is overall width, wheel mounting surface to wheel mounting surface. The reason I say that is because the Granada width rear at 58” has been used a lot in 39-40 fords, and I know for a fact that the overall width of the banjo rear in my 39 is 57.375”.
Outside of obscure bragging rights knowing exactly what vehicle the rear end came out of is insignificant. Some Bubba factor at the spit and whittle club if it came out of something like a big block Mustang but otherwise the pages that Ekimneirbp posted. pretty well tell it all. Wheel bearing size, axle spline count and brake size are the main concerns as most of the rest is just 9 inch Ford as far as gears or differential bearings go. It's a hell of a lot prettier than those F150 nine inch housings I have though.
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