Another broken Axle bolt

[Hog_Johnson]

Did it break going in or coming out?

Coming out

Sponsored

 

[Ed21]

Thanks for the picture.
I'm always wondering why all these pics with broken or removed bolts show the axle NOT flush with the hub. It seems like as you torque the bolt it would draw the axle up against the washer and hub shoulder.
Or put another way, I have yet to see anything about the axle shaft itself that would stop it from coming outboard enough to seat against the bolt. So why are most of the pictures showing the axle inboard a few centimeters?

I guess it's possible that the axle wants to move inboard if the fastener/bolt isn't holding it from moving?

I keep coming up with the questions:
1) Is the axle supposed to be flush with the hub after assembly or does it work itself inboard over time. It's supposedly a press fit into the hub. If the axle can be moved in the hub easily and it's not flush with the hub that bolt is going to break every time from the microscopic flexing in the gap IMO.
2) Was the bolt tight in the axle upon backing it out for replacement? (I assume it was).
3) Is the washer at the inboard part of the spline bottomed out against the hub before bolts were backed out or at any time after assembly? It would be nice if somebody could examine this stuff if they get the opportunity. IMO even if the shaft is a press fit and not flush with the hub that gap poses a problem for that bolt.

 

[Hfyvr]

Is it me or does this axle bolt seem way undersized for the application?

I’m pretty new to the powerboost and F150’s but I’ve been around the VW world for a long time and the axle bolt used on a Golf looks to be around 2-3x the size of that bolt. Something to think about is whether they’re actually applying the right torque specs. For the MK5 VW’s there were a total of 3 different axle bolts available for the same application. Hex head, 12 point with ribs on the mating surface and 12 point without ribs. Took anywhere from 70nm to 200nm plus a quarter or half turn. Huge variance in torque depending on what you received from the dealership and many got over torqued if you didn’t look up the right one.

 

[FirstFord]

Well, it's my turn in the barrel. Just learned moments ago. 14,980 miles. I was really hoping that I was going to be one that skipped past this issue.

 

[Buyer2021]

Well, it's my turn in the barrel. Just learned moments ago. 14,980 miles. I was really hoping that I was going to be one that skipped past this issue.

Bummer.

What's the build month on your door frame sticker, please?

 

[FirstFord]

What's the build month on your door frame sticker, please?

It was built Feb '22. Max Tow Package equipped.

Edit: I did not physically check the door pillar sticker, because it wasn't necessary. I custom ordered my truck, and followed the process closely. If I recall correctly, it was built between the 21st and 24th of February. I took delivery March 17.

 

[John861]

Finally.... A recall for this issue. I'm interested to see what they will replace.

 

[AndreB]

Just linking 2 threads on the same subject.

https://www.f150gen14.com/forum/threads/axle-bolt-sheared.14689/

 

[Gros Ventre]

These axle bolt failures still look to me like a brittle fracture type of failure. In other words a poor alloy bolt or a poorly annealed bolt. As a check, you could get the bolt specs (thread & length) and go buy an off the shelf bolt of the required harness at say, NAPA, or another auto parts store you trust. Put it in and see what happens... Of course, you may want to hold Ford's feet to the fire... on the guarantee... but how many times do you want to keep going back in...?

 

[RossRR]

These axle bolt failures still look to me like a brittle fracture type of failure. In other words a poor alloy bolt or a poorly annealed bolt. As a check, you could get the bolt specs (thread & length) and go buy an off the shelf bolt of the required harness at say, NAPA, or another auto parts store you trust. Put it in and see what happens... Of course, you may want to hold Ford's feet to the fire... on the guarantee... but how many times do you want to keep going back in...?

Since Ford has announced a recall, discussions have died down on make-shift DIY solutions. We are all waiting for Ford to disclose what their final recall solution is going to be.

 

[Snakebitten]

It's definitely become a quiet issue.

Which seems a bit odd because forum members would likely still post if they were experiencing broken axle bolts. I would assume anyways.

I haven't put a lot of mileage on my truck since I used my own approach. (using non-Ford bolts)

But I did just finish a 2200 mile trip and all is well.

 

[Gros Ventre]

It's definitely become a quiet issue.

Which seems a bit odd because forum members would likely still post if they were experiencing broken axle bolts. I would assume anyways.

I haven't put a lot of mileage on my truck since I used my own approach. (using non-Ford bolts)

But I did just finish a 2200 mile trip and all is well.

Roger that Ford has acknowledged a fix... If RossRR thinks about my words above, I'd bet they (Ford), perhaps among other things, have included a replacement bolt of the correct ductility... Hence I'm wondering if Snakebitten's fix above did just that...
I've observed this issue for awhile... And my training in the submarine world says this just looks like bolt that is too brittle. This would parallel my conclusion on Ford batteries seemingly having a bad active material alloy... In this modern world (think Boeing) shaving a penny here and a penny there can appear to add up to savings in the corporate front offices...

 

[Henfield]

I always read threads concerning Axle bolts since my max tow hasn’t had the problem yet but I’ve purchased a new pair of bolts as a quasi shield against it ever occurring. I wish there was a direct cause and affect explanation as to why it occurs but I have an idea.
I have a close friend with years of experience and a very active diagnostic mind and although he has never repaired a max tow axle he offered a theory based on my explanation of the result and the design of the axle. Right or wrong I can see his logic…I’ll pass it on…his theory is that the slight spline/hub looseness is producing a ratcheting effect that over time tightens the bolt since the head of the bolt rubs on the large washer and the perimeter of the washer rubs on the hub. He can give you 30 minutes on theory here but over the years I have learned so much from him that I tend to listen when he speaks. Since all I hear is how to remedy the result of the problem and almost nothing on its etiology, maybe this a start. Perhaps a different washer or sufficient lubrication at the bolt washer/washer hub interface might ward off the breadage of the bolt. Or maybe it’s just bad juju.

That's really interesting. Usually you get afraid of a bolt loosening. Locking washers are the solution in that scenario.

I believe that this is a problem that will afflict vehicles equipped with these axles throughout their lifetime.

Unless there is a design change.

 

[Ed21]

Yeah, like this basic design.

 

[scott011422]

Yeah, like this basic design.

This is basically what we have. Only real difference is that taper on the end of the axle shaft? Thats a press fit spline on our trucks.

Sponsored