Be aware --- the #1 cause of failures in AOD's is misadjustment of the TV. I've heard of it causing a newly rebuilt AOD to fail within 50 miles!! Do the factory procedure for setting it, or pay a trans shop to do it (with a pressure gauge).

Also, some AOD's (mostly earlier than cable-type TV) were an 85% +/- overdrive ratio, in other words not much OD. Later ones are like 72%. That could explain the apparent disparities here.

Good reading Bobby, thanks!

 

1957/67 F100 9 Inch 2WD rear axles are identical. Right/left are the same: B7TZ-4234-A

1968/72 rear axles ARE NOT THE SAME as 1957/67. 1968/72's used 3 different 28 spline axles (2 are right or left specific) and two different 31 spline axles.

I just listed all the differences yesterday. Forum 1948-60 F1, F100; Thread: Nick in axle shaft.

Mcdonaldm = This is the second time you've typed this mis-information regarding all axles interchanging between 1957/72.

The axles WILL NOT INTERCHANGE between 1957/67 and 1968/72 PERIOD!

 

Bill,

I get more and more confused the more I mess with with these danged 9" diffs. (I think thats why I put off swapping my gears out) The diff in my truck is a 1960 unit that I pulled out of a truck I drove in high school and had setting behind shed for all these years. It has the offset third member so it has two different lenght axles but the truck was not a 4x4. Maybe on the day they put my truck together they ran out of the 2wd diffs and I got the offset one.


I have always been confused as to why the offset the rear pumpkin anyway. Anybody got an answer that makes sense?

From what I remember about reading up on these danged axles is that there are several different lenghts as well as several different daimeters at the outer wheel bearing.

Like I said before, it all started making my head swim and I decided that for now I can live with my 4:11's. Maybe this winter I'll try again at going through all the info

Good luck
Bobby

 

In trucks, the pumpkin looks offset in order to have the axles equal in length. This allows for equal axle wrap under heavy loading.

Auto diffs have unequal length axles to put the driveshaft in the center of the frame and run it down the tunnel in the floor.

That's my story....and I'm sticking to it!

 

1960 F100 2 or 4WD

1957/63 Ford Truck Parts Catalog. Rear Axle: Section 40; Parts List #64

2-B7TZ-4234-A .. Axle Shaft

Only axle shaft listed.

Are you sure you have two different length axles?

 

Easy NumberDummy, I don't think he's trying to post inaccurate info. I think he said the differential will swap out as long as the splines are the same. Blue57 doesn't have to change out the axles. He just needs to change out the differential. the 28 spline axles from the earlier years will fit into the 28 splined differential from the later years. He can use his original axles and housing. As long as the new differential fits the housing, all is good. My diff. came from a 70 cougar and I used the original 58 axles and housing.

 

Thanks for that "from the book" solid info NumberDummy. My only concern as to the spline count on the axles was so that I get a "Punkin" that is the same count as my axles, so I wouldn't have to change anything BUT the punkin.

BTW, my friendly local tranny shop owner agreed that the TV is too loose, when I called to see if he could set it for me with a guage. He told me that the guage doesn't always nail it perfectly , sometimes it does, and other times it gives him a starting point for the fine tuning process, he said. A process that could cost me $25 bucks, or $125 depending on how much time he spends tinkering with it.
I had originally set it where the TV was full out at full throttle. He suggested that I set it from the idle position, and adjust the TV where it needs to pull out 1/4" to clip onto the carb linkage. Then play with it from there to get the first shift at about 19 mph and OD ingagement at 45 to 50 MPH. He said that if it is loose and shifts too soft and too early it WILL smoke the bands (due to low oil pressure at low RPM), but if you have it too tight and it chirps the tires with a 25 mph 1-2 shift it will be OK, just rough driving.
That makes sense because I have always heard that a shift kit prolongs the life of a trans because of the cleaner shifts .

 

Bill,

Its 2WD

I'm not even sure where I'm at on most days. The reason I was thinking I had two different length axles is that the center section (pumpkin) is offset to one side. Although now that I think about it that would make the axles the same length. If it were centered then one axle would have to be shorter to account for the ring gear being off to the side of the pinion.

Sorry about that, it turns out its just my backward thinking screwing me up.

Thanks for all the info, its a HUGE help!!
Bobby

 

Yes, you are correct...my apologies mcdonaldm and to y'all. Sometimes I get a bit carried away when I see things I feel aren't right. In this case, I shoulda read the post more thoroughly.

 

According to that I should be cruising at 1828 to 1968 RPMS at 65-70 MPH with my 27 inch 225-75/R15s and 2.26 rear gear, although I like cruising at 60 most of the time (1687 RPM). Thanks for the link!

 

Your Very Welcome.