The Ranger XLT @ Holley Ford Fest 2024 in Bowling Green KY After Missing HRPT 2019 and Power Tour 2021

[Manny]

Yep it is a 28 spline. Bronco graveyard assured me we had the correct bearings for the tru trac.

Yep only trouble with 9 inch is all the bearings one them. They are super easy otherwise so guess you cant complain!

[DuckRyder]

Yes all the bearings are confusing, props to Bronco Graveyard for putting up with my questions, answering them quickly and shipping parts fast.

I went back and re-decoded my door tag and it has Axle 08 (3.50 (3.3M) Ford) (non-locking) just as I remembered and in fact 3.25 non-locking does not appear to have been an option. Scratch that it would have been 17 (3.25 (3.3M) Ford)

My truck is low mileage and the interior of the diff looks low mileage, as you can see the outside of it was quite dirty. So I think the pumpkin was changed early in the life of the truck. I do know the chunk has been out due to the silicone that was on it, but the diff itself does not appear to have been apart. If this is like a day 2 modification I wish the old farmer had sprung for a detroit locker too

I suppose it is also possible I have somehow miscounted the teeth on the pinion (three times) by 1

[Manny]

No probably not. Mark the pinion at the top and count the rotations of pinion to one full ring rotation. Gears can stink that way.

[DuckRyder]

Yup, 3.25... Guess I just need to reach the acceptance phase. Really in the long run I will probably be happier with this...

[DuckRyder]

Other side of ring.

[Manny]

Looks really good. What gear set where you wishing to have???

[DuckRyder]

I had based all my figuring on the 3.50 I thought it was, in retrospect, I noticed recently that the speedometer was off and it currently has a Dana 44 with a 3.54 gear, so it shouldn’t be off, but with a 3.25 > 3.54 difference that mystery is solved. Then too I had always thought I would eventually put a low gear like a 3.89 in it and a gear vendors or a 6 speed manual... That is not happening before power tour though and if I’m realistic with myself the 3.25 will work fine and perhaps even a little better...

So it wasn’t so much I was hoping it was a 3.50, I just always thought it was because I figured it was the original gear per the door tag. It never even occurred to me that someone had changed the gear, I just figured the silicone was due to someone changing the gear oil. It wasn’t until I started cleaning it up and saw the black paint that was sprayed on it that it occurred to me that there might be more to it.

[Manny]

I had based all my figuring on the 3.50 I thought it was, in retrospect, I noticed recently that the speedometer was off and it currently has a Dana 44 with a 3.54 gear, so it shouldn’t be off, but with a 3.25 > 3.54 difference that mystery is solved. Then too I had always thought I would eventually put a low gear like a 3.89 in it and a gear vendors or a 6 speed manual... That is not happening before power tour though and if I’m realistic with myself the 3.25 will work fine and perhaps even a little better...

So it wasn’t so much I was hoping it was a 3.50, I just always thought it was because I figured it was the original gear per the door tag. It never even occurred to me that someone had changed the gear, I just figured the silicone was due to someone changing the gear oil. It wasn’t until I started cleaning it up and saw the black paint that was sprayed on it that it occurred to me that there might be more to it.

SOOOO if i said i have 3.50 gears your welcome to have does that mess you up worse??

[DuckRyder]

If you have a nice set of 3.50 you’d be willing to trade we could do that... I can hustle up a speedo gear...

[Manny]

If you have a nice set of 3.50 you’d be willing to trade we could do that... I can hustle up a speedo gear...

No trade needed so many times bronco guys bring a 9 inch with 3.50's by and then want 4.10 4.56 so there you go.

[DuckRyder]

Sweet! I’ll take care of you on this!

[DuckRyder]

Boy...

So speedometer gears... Seems it should have an 8 tooth drive gear. I believe it came with G78 15. G78 15 roughly equal to 215/75/15 which is on it. (~27.6”). The calculator on Cobra Jet registry comes up with Driven gear: 20 teeth, C8SZ-17271-B (Orange) for a 3.50 gear.

What I can find a
1972 F100 with G78 15 would have come with Driven gear: 21 teeth, C4OZ-17271-A (Red)
1972 F100 with 700 15 (~29.5”) would have come with Driven gear: 19 teeth, C0DD 17271 C (UNK)



Guess I’m crawling under it...

[DuckRyder]

OK, it has an 18T, white. I believe it is not OEM, has 18T and 1D or D1 or similar on it. Green is sharpie used to highlight.

I’m kind confused about if it is type 3 or 3A from NPD catalog.







I can’t find the page of the MPC that shows the 3.25 part of the chart for C6 (Section 172, page 59 I believe) but the page I can find (60) which list the above for a 1972 F100 also list a 18 or 21 for a 71 with G78 15 with a serial number change at L000001 which is rather confusing since the drive gear teeth are listed as the same.

I think I will put a 20 tooth in it and see what happens...

[Ranchero50]

I have a bunch, but no 20's. Last time I needed some I went to the dealer. I think they were around $15 each. Been a decade or two but it's an idea.

[DuckRyder]

I ordered a few from NPD, I need a couple other things anyway.

I’m still a little confused about the Type 3/3A deal but it looks like Type 3 are long snout which I don’t believe is correct for a C6.

Looks like a RH 3A 20T gear is black.

They were bout 5 bucks each, so I just got a 19,20, 21T...