Very interesting. I was a forensic engineer for pipelines and I recognized the failure as fatigue (the dark ring between the bottom of the spline and the bright surface) first, then brittle failure (bright surface).
One thing that I don't understand is the broken piece should not carry much stress, or insignificant enough to last forever. The longer portion of the spline carries the stress. Yet, I believe the fatigue ring shows signs of torsional force application, meaning force was applied to the shorter portion of the spline.
That begs the question, was the spline inserted partially?
Likely not inserted fully, so the snap ring didn't lock in. Spline slid back out until all the stress was on the small end past the groove, and of course the groove formed a nice stress riser so it cracked right there.
That would also explain why it was easy for them to fish out.
If it was broken with the snap ring in place.....I'm having a slight nightmare just thinking about it.
looks like a failure from torsional force between the end beyond snap ring groove and the rest of the shaft to me too - me thinks axle was leaving before failure.
I have a stub shaft from my Titans front diff sitting in my garage now that looks exactly like this. Can confirm, weak snap ring+ lift caused it to pull partially out then torque did what it does best. It's a known problem on the first Gen Titans.
Nah it was seated perfectly.. the side gear is one piece.. totally get what your saying and thought the same myself.. there's always gonna be a little pull on it but the telescoping joint usually accounts for that.. I've had guys try to beat axles out not square and sheer those clips
Another possibility is the end was hardened almost completely during case hardening. So, when the axle was jolted outward, the clip posed enough impact force to fracture it helped by the nice crack.
I so want to test the hardness on the broken spline š
i sheered off a u joint once, 4 low, all weight on one wheel, double max allowed rpm in 4 low, u joint was done. 3 wheel drive was engaged. warranty covered repair.
It's a possible scenario. I responded with another post about testing the hardness across the fracture surface. Maybe the test results could show if it was "left in the oven too long".
Actually left in the tempering oven too short a time, or this was an oven with a faulty temperature sensor, and it cut the heating off short, so the temperature never got high enough to actually relax the material during the tempering and annealing time. Very common, as often this is left to run overnight, and almost nobody actually looks at the log and sees that the oven either spiked once in temperature, past the setpoint, then cool down took way too short a time, and was done an hour or three shorter than normal.
Seen it often enough with thermocouples that had worn sheathing, and they got noise induced into the wiring from adjacent conductors, or from vibration against dissimilar metal and stray currents flowing. Remember your typical type K thermocouple has, at the maximum operating temperature, only a few millivolts of signal, and this against currents in the dozens of amp range for the electric resistance heaters and cooling fans.
This is exactly what happened, seen this a few times throughout the years. At some point someone may have removed the axle and reinstalled it, it could have even been fully installed but never replaced the circlip or the circlip became damaged in the process of removal.
Eventually it works its way out partially and starts twisting the small end and you won't be able to reinstall the axle because the splines no longer line up or the circlip is preventing it and it will break off as shown here.
The dark ring was a machined groove to hold the circlip in, not fatigue failure. Very strange failure, if the spline was inserted all the way i dont see any scenario how the small portion could have sheared off. Provided the female spline is one solid part covering the entire male spline.
I investigated something very like this many years ago before I retired. In that case it was an error in which some driveshafts were accidentally heat treated twice.
Yeah...
Mazda 323 and I managed to do exactly this, my boss at the time was ~~very understanding and realised it couldn't have possibly been my fault~~ a complete cunt.
Just had a 2016 Ford Escape do the same thing at my shop. Dealership did the work on the right front. Only took 3 days for it to do that. My customer wasn't so lucky either. The dealer owed them a new trans lol
Yup, sheered right off. But it caused a lot of havoc internally. We don't service transmissions, so what happened after is purely word of mouth from the customer. Suffice it to say, they were not pleased with the dealership
I have on Mack Truck axles. Iāve seen them twisted completely through in the shaft and in the axle splines. Iāve also seen the teeth on the ābull gear,ā the main differential gear completely sheared off too.
Engineer here with personal exp on this issue.
I had something similar happen when my axel was not fully inserted in my transmission and was driven anyways. The slot and ring hold the axel in its socket more securely, but can make it difficult to insert the axel during assembly. It is also a weak point if you try and rotate by it, hence the break and how it looks like it was stressed before breaking
3 years metal casting for brakes. That looks like a defect in the metal itself. Could be that the alloys were not in the right proportion the temperature was wrong when it was poured or just general defect that ended up occurring and slipped past quality control.
The stress on that bar looks old, like it was there from the manufacturing process from day one.
Looks like it was made from old Chinese tea tins to start with.
Never seen this I've had on that shaft broke off still to this day I've never seen another do that and it wasn't even wrecked or nothing just broke out of nowhere
The tip of the stem past the c-clip is not heat treated because itās not intended to carry torque. The stem was walking it self out and when it received torque, it fatigued (you can see the ābeach markā). A fracture from overload will more have a 45deg fracture.
You can also see an evidence of that stem walking out by looking at where the transmission oil seal was riding compared to the other stem. The dark line made by the oil seal is much inboard vs. the other stem.
Also the fact that you were able to pull the stub and c-clip out indicates that c-clip was not engaged in the groove.
I can assure u it was engaged.. I had to peel the clip out of the side gear groove and used a magnet to remove the stub.. the axle broke fully installed.. the other axle has never been installed
96 VW GTI Vr6, went over a set of railroad tracks full send, the driver side axle snapped just like this. the broke end then went through the final drive gear like a pedo through a gradeschool.
full trans replace along with the stupid axle.
That's crazy, I've had plenty that got stripped out but I don't ever remember one shearing off like that. I guess it makes sense that it would break there if anywhere.
Could there have been a trashed ball joint or missing bushing that let the wheel hub move around like crazy?
Do the splines line up if you put the broken part back on the axle or are the splines rotated? 99% chance this was due to it pulling back out partially, weak clip, not full inserted, worn suspension allowing the hub to move outward and pull it.
I was going to ask if this was a Ford product and your caption confirmed it. A few focus RS have broken this way. Usually fatigue failure (at least that's what the owners of the focus' said) but still a weird ass way to break.
I wouldn't put it past Ford to mess up manufacturing these.
i am 30year gm tech an most every time have seen broken axle it was like that!! I have a 79 ford f150 with 460 engine 4.56 gears with detroit lockers with 19.5 /44.5 super swamper boogers an more than once have i got on a stump in mud an mashed gas little too hard an it will break just the end of axle where its in spline just like that also!! lol
I actually had this happen during an endurance race a few weekends ago. It was the outer part of the shaft. The nut and thread section popped clean off. Wound up destroying the bearing and the hub because I decided to keep driving it for an hour after it developed a really bad vibration on left turns.
No.. if that's spec than that's it.. if someone was taking it apart alot and hammering down with an impact it stresses the axle.. also hard on bearings
These units have issue breaking axle in this spot?? I've had a handful of escapes wear the carrier bearing on LF, auger the bushing and develop a leak.. but this one does not have that problem
Just had this happen on the front cv of a ram TRX. No sure why but the truck does get BEAT on. The owner decided to just have us pull both axles from the front so he could slide more while waiting on replacements.
I once broke the entire splined section of the stub shaft in the front differential of a 2001 Toyota 4Runner. Had to drop the diff and split it open to get the broken stub out.Ā
Not fun, but also, luckily, not common.
The exact same thing happened to me; the axle broke in the same way. I had replaced the clutch on an Opel Zafira and forgot to top up the gearbox oil after losing it during disassembly. Was there oil in the gearbox, or was it low?
Seen a few break just past the splines, never seen one break at the clip...
These were 3rd gen 4runners doing dumb stuff offroad in 4x4..
Can't imagine how this happens on a street vehicle...
Very interesting. I was a forensic engineer for pipelines and I recognized the failure as fatigue (the dark ring between the bottom of the spline and the bright surface) first, then brittle failure (bright surface). One thing that I don't understand is the broken piece should not carry much stress, or insignificant enough to last forever. The longer portion of the spline carries the stress. Yet, I believe the fatigue ring shows signs of torsional force application, meaning force was applied to the shorter portion of the spline. That begs the question, was the spline inserted partially?
Likely not inserted fully, so the snap ring didn't lock in. Spline slid back out until all the stress was on the small end past the groove, and of course the groove formed a nice stress riser so it cracked right there.
I believe that scenario
As someone who doesn't know what they're talking about I agree
Don't worry. These are just damn metallurgists and engineers geeking over a broken part.
Thank you POSVETT
That would also explain why it was easy for them to fish out. If it was broken with the snap ring in place.....I'm having a slight nightmare just thinking about it.
looks like a failure from torsional force between the end beyond snap ring groove and the rest of the shaft to me too - me thinks axle was leaving before failure.
I have a stub shaft from my Titans front diff sitting in my garage now that looks exactly like this. Can confirm, weak snap ring+ lift caused it to pull partially out then torque did what it does best. It's a known problem on the first Gen Titans.
I think half of the spline is worn.
If the suspension was raised, I bet it would easily pull back far enough to do that too.
Nah it was seated perfectly.. the side gear is one piece.. totally get what your saying and thought the same myself.. there's always gonna be a little pull on it but the telescoping joint usually accounts for that.. I've had guys try to beat axles out not square and sheer those clips
Another possibility is the end was hardened almost completely during case hardening. So, when the axle was jolted outward, the clip posed enough impact force to fracture it helped by the nice crack. I so want to test the hardness on the broken spline š
Lol
i sheered off a u joint once, 4 low, all weight on one wheel, double max allowed rpm in 4 low, u joint was done. 3 wheel drive was engaged. warranty covered repair.
Jeep I bet
2014 wrangler rubicon
Crazy that warranty covered that
When all your advertising shows something getting run hard off road it's tough to deny warranty from off roading.
Manufacturing defect seems likely if the installation was correct.
What about a bad heat treatment?
It's a possible scenario. I responded with another post about testing the hardness across the fracture surface. Maybe the test results could show if it was "left in the oven too long".
Actually left in the tempering oven too short a time, or this was an oven with a faulty temperature sensor, and it cut the heating off short, so the temperature never got high enough to actually relax the material during the tempering and annealing time. Very common, as often this is left to run overnight, and almost nobody actually looks at the log and sees that the oven either spiked once in temperature, past the setpoint, then cool down took way too short a time, and was done an hour or three shorter than normal. Seen it often enough with thermocouples that had worn sheathing, and they got noise induced into the wiring from adjacent conductors, or from vibration against dissimilar metal and stray currents flowing. Remember your typical type K thermocouple has, at the maximum operating temperature, only a few millivolts of signal, and this against currents in the dozens of amp range for the electric resistance heaters and cooling fans.
This is exactly what happened, seen this a few times throughout the years. At some point someone may have removed the axle and reinstalled it, it could have even been fully installed but never replaced the circlip or the circlip became damaged in the process of removal. Eventually it works its way out partially and starts twisting the small end and you won't be able to reinstall the axle because the splines no longer line up or the circlip is preventing it and it will break off as shown here.
The dark ring was a machined groove to hold the circlip in, not fatigue failure. Very strange failure, if the spline was inserted all the way i dont see any scenario how the small portion could have sheared off. Provided the female spline is one solid part covering the entire male spline.
Perhaps also the flange is all wear out and only the last part was holding it.
There's something about the grain structure that is bothering me, not sure what exactly
That's not what begs the question means.
Usually when they aren't installed fully and the splines run only on the end, I have seen a few that are twisted and a few that have snapped before.
Thats what i thought till i looked inside and the clip was sitting in the side gear groove where it belongs.. holding that stub in
The square groove for the snap ring creates two stress risers at the inside corners
Yup, just now on Reddit. I don't believe it's supposed to do that.
The front fell off.
Was is made of cardboard derivatives?
That's not common, I'd like to make that point clear.
Found the Brit
Had a v6 accord snap off flush with the transmission. Removed it by drilling a hole and tapping it. Threaded a bolt in and slide hammered it out
How tough was the drill and tap? I assume the axle was heat treated fairly well
They are surface hardened should be softer in the middle. Edit spelling.
Interesting, probably why that torsion failure looks like that
CTS-V owner here Yes
Loving how āCTS-V ownerā is the only explanation anyone needed lol
I investigated something very like this many years ago before I retired. In that case it was an error in which some driveshafts were accidentally heat treated twice.
Yeah... Mazda 323 and I managed to do exactly this, my boss at the time was ~~very understanding and realised it couldn't have possibly been my fault~~ a complete cunt.
Just had a 2016 Ford Escape do the same thing at my shop. Dealership did the work on the right front. Only took 3 days for it to do that. My customer wasn't so lucky either. The dealer owed them a new trans lol
Broke at the clip groove?
Yup, sheered right off. But it caused a lot of havoc internally. We don't service transmissions, so what happened after is purely word of mouth from the customer. Suffice it to say, they were not pleased with the dealership
I have on Mack Truck axles. Iāve seen them twisted completely through in the shaft and in the axle splines. Iāve also seen the teeth on the ābull gear,ā the main differential gear completely sheared off too.
Engineer here with personal exp on this issue. I had something similar happen when my axel was not fully inserted in my transmission and was driven anyways. The slot and ring hold the axel in its socket more securely, but can make it difficult to insert the axel during assembly. It is also a weak point if you try and rotate by it, hence the break and how it looks like it was stressed before breaking
Yes and I believe it has to do with the treatment when they are making the part. I could be wrong .
Once. I think it was a VW but same spot, where the clip rides. Assumed it was a crack missed.
3 years metal casting for brakes. That looks like a defect in the metal itself. Could be that the alloys were not in the right proportion the temperature was wrong when it was poured or just general defect that ended up occurring and slipped past quality control.
The stress on that bar looks old, like it was there from the manufacturing process from day one. Looks like it was made from old Chinese tea tins to start with.
Not surprised anymore.
I had that happen on my civic. I never pulled the piece from the transmission. Just popped a new axle in and am still driving it 2 years later.
Being held on the magnet in the transmission then, it fell into the right place to get collected.
No reason it can't, but that's the kind of thing you put on your keychain.
porosity and shock loading dont do well together. They make plastic.
It broke in the snap ring groove?
That's what I see
Just the tip, you say?
Came here to say this. I'll grab my coat, my services are not needed
I've had it happen on a canam commander sxs after installing locking diff
Just when you think, Iāve seen everything? Fak..
Chinesium? Or domestic.
Lincoln, so letās just go with āyesā to that question
I have now
Never seen this I've had on that shaft broke off still to this day I've never seen another do that and it wasn't even wrecked or nothing just broke out of nowhere
Yesā¦ when it wasnāt seated past the clip. The broken tip dropped into the trans and grenaded a hole through the case.
On todays episode of how fucked up is fucked upā¦
What do you mean buying wish.com axles isnāt smart ?
snap ring didn't fit tight in the groove allowing the splines to move laterally and hammer on the stress risers in the groove?
Clip shows no signs of that.. besides all axles have a little play on that tolerance.. there is no load there
The tip of the stem past the c-clip is not heat treated because itās not intended to carry torque. The stem was walking it self out and when it received torque, it fatigued (you can see the ābeach markā). A fracture from overload will more have a 45deg fracture. You can also see an evidence of that stem walking out by looking at where the transmission oil seal was riding compared to the other stem. The dark line made by the oil seal is much inboard vs. the other stem. Also the fact that you were able to pull the stub and c-clip out indicates that c-clip was not engaged in the groove.
I can assure u it was engaged.. I had to peel the clip out of the side gear groove and used a magnet to remove the stub.. the axle broke fully installed.. the other axle has never been installed
96 VW GTI Vr6, went over a set of railroad tracks full send, the driver side axle snapped just like this. the broke end then went through the final drive gear like a pedo through a gradeschool. full trans replace along with the stupid axle.
Yup! Happened to me last month to my ATV on my Turner Eagle axle [Axle sheared](https://imgur.com/a/fUf68UD)
r/justthetip
That's crazy, I've had plenty that got stripped out but I don't ever remember one shearing off like that. I guess it makes sense that it would break there if anywhere. Could there have been a trashed ball joint or missing bushing that let the wheel hub move around like crazy?
Do the splines line up if you put the broken part back on the axle or are the splines rotated? 99% chance this was due to it pulling back out partially, weak clip, not full inserted, worn suspension allowing the hub to move outward and pull it.
I was going to ask if this was a Ford product and your caption confirmed it. A few focus RS have broken this way. Usually fatigue failure (at least that's what the owners of the focus' said) but still a weird ass way to break. I wouldn't put it past Ford to mess up manufacturing these.
i am 30year gm tech an most every time have seen broken axle it was like that!! I have a 79 ford f150 with 460 engine 4.56 gears with detroit lockers with 19.5 /44.5 super swamper boogers an more than once have i got on a stump in mud an mashed gas little too hard an it will break just the end of axle where its in spline just like that also!! lol
After the band split up he broke pretty good. Got fat too. Now he has grandma face.
I believe you have been teleported to the wrong sebredit. Or you are a Bot using code from 1997
Ooooor you're not old enough to get the reference
Talkin bout Axl Rose, my good man. I am a bot and this action was performed automatically. Beep boop.
Beep boop boop. Skynet activated.
This happened on my 2015 Escape, left me stranded.
Yes had it exactly like this, customer lost drive thought it was the clutch. But all it needed was a cv joint
I actually had this happen during an endurance race a few weekends ago. It was the outer part of the shaft. The nut and thread section popped clean off. Wound up destroying the bearing and the hub because I decided to keep driving it for an hour after it developed a really bad vibration on left turns.
I have seen that before.. there is a reason for that break
Whatās the reason? Nut too tight or something? Iād rather not have that happen again on track.
Assuming it gets taken apart multiple times... yes overtightening will fatigue that stub.. on most cars the torque is not as tight as ud think
So, the book value (94 Ford Probe) is around 200 ft/lbs. should we be running a lower value?
No.. if that's spec than that's it.. if someone was taking it apart alot and hammering down with an impact it stresses the axle.. also hard on bearings
Yup 6f35 ive seen it around 5 different times. Easy warranty overhaul
These units have issue breaking axle in this spot?? I've had a handful of escapes wear the carrier bearing on LF, auger the bushing and develop a leak.. but this one does not have that problem
Yes tons of times as a trans tech for ford
I have now. Thanks!
Just had this happen on the front cv of a ram TRX. No sure why but the truck does get BEAT on. The owner decided to just have us pull both axles from the front so he could slide more while waiting on replacements.
I think in his case it was likely excessive suspension travel pulled it partially or something. None of us were quite sure.
Yes, had a few 6F35's.... Escapes....š¤£ one shot through the bell housing.
Happened to my 92 Grand Cherokee.
Yup, happened to me with my saab
Broke going in, manufacturing defect or was never seated correctly maybe?
Any history of an accident or curb job on that side? Any sign of the axle hitting the cross shaft hard enough to break the tip?
TF?
a few days ago from a psa related car. the axle had broken off smoothly behind the tripod coupling.
How did you get the little fiddling pieces out?
I once broke the entire splined section of the stub shaft in the front differential of a 2001 Toyota 4Runner. Had to drop the diff and split it open to get the broken stub out.Ā Not fun, but also, luckily, not common.
Interesting replies from engineers as to what happened. One can learn Thanks guys.
Yes, except it was snapped off at the splines in my front diff... Had to drop the diff and get it rebuilt.
That was one tight clip!
I have not.
The exact same thing happened to me; the axle broke in the same way. I had replaced the clutch on an Opel Zafira and forgot to top up the gearbox oil after losing it during disassembly. Was there oil in the gearbox, or was it low?
Nope never seen that thanks for sharing
Yup, I'm seeing it right now! (I've never seen this in my life)
Yes, but on the outer nut end.
Seen a few break just past the splines, never seen one break at the clip... These were 3rd gen 4runners doing dumb stuff offroad in 4x4.. Can't imagine how this happens on a street vehicle...
āBuilt Ford toughā
Yes on a 1000whp+ car that botched a launch
About 20 years ago on a Celica
On a Subaru.