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Diff question

Track T-4

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Supporting Member
I'm relatively new to the site and to owning a T. Bought mine a couple of months ago and am getting it ready for the upcoming season. The PO owned the car for several years so I'm working through undoing some of his "tweaks" and discovering the origin of some of the parts - differential, engine, brakes, etc. :confused:

My question here is what diffferential is under the car - an 8" or a 9"? The PO said it is an 8" but I have a feeling it is a 9". The car does not have an e-brake and I plan to install a pinion-mounted e-brake from TP so need to know which diff it is. I tried to post photos here but wasn't able to so there are a couple in my vBPicGallery, they're not the best and there is still some dirt and missing paint but hopefully the're clear enough. Any help would be appreciated. Thanks!
Not a hundred percent, but pretty sure thats an 8" rear.
The easiest way for me is to look at the lower bolts that hold the 3rd member(chunk) in the case. There is one bolt on a 9", under the pinion bearing housing, that can only be turned with an end wrench. A socket won't fit. If you can get a socket on all the lower bolts, it's an 8".

This method has always worked for me, especially if you're wandering around a junk yard.

Thanks for the feedback guys and for posting the photos. :dance: I checked with TP and the suggested socket test is used on the lowest bolt on the passenger side of the differential which, unfortunatly, is not in the photo. I can't get a socket on that bolt so it appears to be a 9". Interestingly, the yoke measures as a Chevy instead of a Ford (smaller dimensions). Pete at TP said in certian years Ford used Chevy yokes on some of their differentials so that is not unusual. I have the e-brake kit on order now so I'll see if everything fits when it arrives. I haven't had any luck finding a part number yet so I'll crawl around somemore and see if I can find it.

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