9" Ford Ring Gear Bolts.....

[Sean]

I took an open differential apart today with the intent of putting a clutch-type posi unit in it. I got the ring gear off the open diff and when I put it on the Posi diff, I found that the Bolt heads are too big. They will fit into the counterbores on the posi, but don't leave enough room for a socket. On the open diff, the flange is flat with no need for counterbores.

Does anybody know what kind of bolt is required for this? Can I just go find some grade 8 socket head bolts, or are ring gear bolts special?


(and the posi is in a lot better shape than it looks in the pics, just the outside is rusty)

[Sean]

I have been looking all over the internet at these Trak-Lok differentials and now I'm not so sure I want it in there anyway. Seems like the main problems are ineffective "posi" action, and short lifespan on the clutch packs. A couple websites said 30,000 miles was the life expectancy of the Clutches.

Maybe I should just pull my Locker apart and use it with the 3.08 gears instead. At least I would already have the right bolts... :?

[enjenjo]

Socket head cap screws will work. The stock Posi bolts have a smaller head, if you are not in a hurry, I could probably find a set around here, and send them to you, but you never can tell, an "old" guy like me may not remember where they are.

[Sean]

I could probably find a set around here, and send them to you, but you never can tell, an "old" guy like me may not remember where they are.

Old Guy....Hehe


Thats mighty nice of you, thanks for the offer. Last night I decided to just take the Locker out and use it instead of the TrakLok. The Clutches in the traklok look to be about half worn out, where on the other hand, I know the Locker is in 100% condition(and the right bolts are already there). I'll just set the open diff up with lower gears and a Mini spool for the off chance that I might actually take it to a dragstrip.

Doctor has released me to 5lbs and no bending, and my boss called yesterday afternoon to tell me to be at work Monday morning. Looks like I need to get off my Butt and get that Diff swapped over today or tomorrow.... Good thing I have a little brother that owes me a couple of favors, I can get him to do all the heavy stuff.    

[Phil55]

As you know by now, the TracLoc uses different ring gear bolts.  But, now that you aren't using the TracLoc, that's a bit of trivia for future use.

I might be interested in the TracLoc.  Is it 28 or 31 spline?

[Sean]

As you know by now, the TracLoc uses different ring gear bolts.  But, now that you aren't using the TracLoc, that's a bit of trivia for future use.

I might be interested in the TracLoc.  Is it 28 or 31 spline?

28 spline. I was going to run it like it is, but it could definitely stand a new clutch pack in it.

[enjenjo]

It's an easy rebuild, the hardest part is getting the ring gear off. Parts run about $40 for a clutch pack. FWIW, the posi case in not as strong as an open case.

If you look to the right side of your second picture, you will see a hole where the clutch pack is visible. If you look at the edge near the bolt hole, you will see that the case is only about 1/8" thick at that point. It will break using the 4 holes, and the counter bores for the ring gear bolts as a guide. It's not pretty at that point.

Why not take the open case and put a minispool in it? Of course if you still have the 66 axles, you might want to change to the later F100/150 31 spline axles, even the later 28 spline axles are stronger than yours.

[Phil55]

Drop me a line at phil.bennett@juno.com if you want to part with the TracLoc.

[Sean]

Drop me a line at phil.bennett@juno.com if you want to part with the TracLoc.

Well, I would have, but I ended up having to use the TracLoc anyway. I swapped the 3.08 Ring gear onto the Locker, then when I went to put it in the other carrier I found out it had smaller Bearings than what was on the Open diff.

I ended up using Grade 8 Bolts from Ace. They had a 5/8" head instead of 3/4" like the originals. I was able to get a socket on them allright, hopefully the smaller head doesn't make a major difference in strength. I'll just make sure I have the Cell phone with me for the first week or two....

So whats the deal with the Bearings? The open Diff Carrier was the original one that came on my Truck. So does the smaller bearings mean the Locker came out of a Car?

[Sean]

It will break using the 4 holes, and the counter bores for the ring gear bolts as a guide. It's not pretty at that point.

I can see why. Looks like when it was machined on the inside for the Clutch Pack, something wasn't quite centered up and they cut through on about three of the counterbores. You could actually see the clutch pack in those spots.

Too late now, its in there. I'm not very happy with the higher Gears, after driving it around a while. I didn't realize how much difference there was between 3.90 and 3.08.  I think I am going to have to split the difference and order a 3.55 gear set. They will go on the Detroit Locker though.

[enjenjo]

The factory bolts for a posi have 5/8" heads, it shouldn't be a problem.

The small bearing, big bearing carrier doesn't mean much outside of the date it was built. Ford used both in pickups. There are bearings available to use a big bearing gear case in a small bearing housing, and vise versa. the only real difference, you can't use 31 spline axles in a small bearing carrier, the hole for the axle is too small, and can't be opened up to clear a 31 spline axle without weakening the case too much.

You can use the 3.90 gears, just switch to 36" tires  

[Sean]

You can use the 3.90 gears, just switch to 36" tires  

Yeah, that would make quite a difference. I think the tires on it now are around 27" tall. I don't think that would help the "needs to be lower" issue though...