Ok, this probably isn't Ford/Sterling's problem, but an idiot mechanic before me.

I went to drop the rear driveshaft so that I could get the center carrier bearing replaced. I went to disconnect the rear yoke/driveshaft connection. What do I find? 4 darn TORX head bolts. 2 are stripped. I had to work the driveshaft side to side to finally get these bolts out.

Does anyone know what size of normal allen head bolts I can put back in there? It's kind of impossible to get a socket on them. I assume that a regular hex head bolt won't work because of clearance issues.

Thanks for any ideas.

 

Ford put the 12-point heads on there, and used threadlocker (or interference threads), so they're super tight. They're also metric. I think they're 10mmx1.25mm, but I'm not sure.

 

Those maybe the ones that I have. I brought one in to work with me so that I can get some new ones. They have 6 points on the inside of the head, just like a TORX, they are 3/4" long, 5/16" diameter, fine threads. I don't have a metric size chart to stick them in. I guess it is off to the parts store at lunch to see if I can find replacements. Probably some special tool that fits in there without a problem to work these things, or some other shop replaced them with these.

Thanks Steve.

 

Steve, FYI

I just went to a parts house. Those bolts are 5/16" fine thread. Tried Metric, but I couldn't find a fine thread 8mm like these. All were coarse. I tried a 5/16" nut on it and it fit great. No play.

I don't know if they were changed or what.

Confusing. I'm gonna try a regular hex head bolt and see if it will turn with the collar in place. The only 5/16" hex head bolts I could find were stainless steel.

Thanks again.

 

0.31496 8 mm
0.3125 standard
--------
0.00246 difference

There really is no difference EXCEPT in the thread
pitch and a few estoric things about how SAE and
metric have slightly different mating surface actions.

If you use a die/tap set you can not tell the difference
when reaming a new hole, that is for sure.

You can not really tell the difference on this size
until it is torqued, loosens up, and then falls out.

Considering you are putting it in the rear end where
failure means sure disa$ter, I would look up the Ford
spec or bolt and get it.

Knowing Ford and having dealt with my Aerostar replacing
wierd size metric bolts, if you need five,
they are sold in bags of four.

I have gotten 8 mm 10.8 fine thread bolts from NAPA before.

 

I just called the dealership that I go to for parts.

The bolts are:

5/16"-24pitch

So, they are SAE fine threads.

Thanks for the help guys.

BTW, I need 4 and they have 5, sold individually at $2.

 

97 f150 4x4 4.6 auto esof:
I had my driveshaft assy off a few times with no problems with the TORX bolts.
That is as long as you are using a 12mm wrench and not a standard.
Those bolts have to be torqued to 70-90ft/lbs any other design head may not take the load. I would just replace them with some new ones.....their only $1 each.

 

97 - dealer said the only description was 5/16 - 24. That is 5/16", 24 pitch thread (i.e. fine thread).

Below is why I hate them. They were like this when I took them off. I knew if I stripped them even more, I was hosed.



Anyway, thanks all. I got some grade 8 same style, but allen head(sunk in like torx) to put back in it.

 

I don't think those are the originals. All the ones I've ever seen have 12-point heads - that a regular 12-point socket would fit over. I've got a handfull that I've collected recently in junkyards off of pickups, Explorers, & Expeditions. I had my rear axle rebuilt with a flange, so I'll be using them now, instead of the older yoke & U-bolts.

 

I agree, I think that someone has changed these before. Ford has used the 12mm 12 point headed bolts for years, At least the early 80's for sure.
Jimmy

 

These just thread into the yoke, with a horse shoe shaped braket that holds the pinion caps. Kind of like a pipe hanger.

Glad to hear that I might not be totally insane. I was really starting to wonder what the heck was going on. I tried a normal hex head 5/16" for grins last night. It won't go all the way down, as I figured.

I am going to get some bolts similar to these, grade 8, but with an allen head, instead of TORX.

Those Torx bolts really torqued me.

Thanks again, guys.

I do like the Corporate set up better, with bolts that go all the way through the pinion yoke.

 

Dude, those internal torx bolts you show are not OEM, it should be external TORX bolts that work perfectly. I had mine off two/three x with no problems.
Just go to ford and get the real OEM parts......their cheap.

 

You're working on the FRONT of the rear driveshaft, right? Where it connects to the t-case? Does it look like this? I'm using hex-heads on that bracket (in the pic) on my truck. I thought you were at the BACK of the rear shaft - that's where the 12-point heads go.

 

Steve,
I was working on the back driveshaft, where it connects to the rearend, at the pinion yoke. Where the rear driveshaft goes into the t-case, it has a slip yoke. I should have taken a picture. But, I don't have a digital camera at home, only at work.

It's similar to a front driveshaft, but instead of U bolts that go through the yoke, it has a half round bracket that is bolted directly to the yoke. The yoke is threaded.

I don't have a double cardon joint. I have a two piece driveshaft with a carrier bearing. Three piece if you count the slip yoke.

 

OK This is what it should look like.

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