I understand that, but increasing the strength of the shaft by heat treating it will still make it more resistant to yield and fatigue failure. It will still break in the same place, but it will take a lot more beating before it does. For the cost vs a billet shaft I think it's a good solution.
Broke my output shaft at the track
- Thread starter BUST'EM 504
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I understand that, but increasing the strength of the shaft by heat treating it will still make it more resistant to yield and fatigue failure. It will still break in the same place, but it will take a lot more beating before it does. For the cost vs a billet shaft I think it's a good solution.
There was a company that was making billet shafts and they left the void in both the input and output shafts. They consistantly broke.
If you break a shaft, why not go with a quality billet. Figure if it has to come out again you are losing money and time.
If you break a shaft, why not go with a quality billet. Figure if it has to come out again you are losing money and time.
I went with the billet shaft. Told them stock first then the more I thought about it I knew it was a bad decision. Thanks guys for the words of wisdom
My guess is it had to do with either the material or the heat treat they used. Just making a part from billet doesn't automagically guarantee it will be better.
Believe it or not a radius that is the minor diameter of the splines makes for a more fatigue resistant shaft than one that runs the splines out to the major diameter. It has to do with stress concentrations and building of stress risers at the male-female spline interface. That said, I completely agree with you that the stock fillet is too deep (about .100" smaller than the spline minor diameter), so eliminating it would make for a stronger piece. Reducing it to the spline minor diameter (1.350") would be even better yet. Better still, the splines don't need to be as long as they are, so reducing their length to one diameter (1.475") or a tad less would cause zero loss in strength at the splines, but having an inch or so of minor diameter shaft between the splines and the threads would result in a HUGE stress concentration reduction. Instead of the torsional stress being concentrated over a .050" wide area at the bottom of the fillet it would be spread over an inch or so of shaft, which would reduce the stress concentration over any point of that section of the shaft by 95%.
Here's an example of what I am talking about:
That is a 32 spline shaft I made, but it illustrates the concept. There is about an inch of minor diameter shaft between the splines and the threaded area, with large fillets at both ends. Also, the male splines are completely inside the mating female splines, so there is no stress riser from a male-female interface. This is the strongest way of making a shaft.
BTW, is the 2011 LML trans still 29 spline output, or did they go to 34 spline like the Fords? The easiest way to make a stronger shaft is to make it bigger
EDIT: I agree that using a QUALITY billet is a good idea. I was just offering an alternative. :hug: The stock shafts are actually made of good material, but they simply aren't hardened to their full potential.
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Seems what you don't get is doing it as you suggested, the failure will cost a lot of money. The tow bill will cost more than a quality billet shaft. the labor will run 1'000.00 dollars depending on the shop and you still have to fork over 600.00 for the new billet shaft plus fluid. What about what you spent for heat treating and the labor to install the shaft? You have an engineering mind and most engineers are idiots when it comes down to common sense. When you guys make a mistake; the best we get from you is an oops and I will go over my figures again. You guys take no responsability for your screw ups. I love when you guys say, " On paper it looks great " Bet you would be more carefull if YOU had to pay the bill for your screw ups. But you don't and you guys still throw your crap out there.
I just got done working with Raybestos engineers on a clutch project and they totaly screwed it up. They did not take the information and tech that I gave them because they know better. After all, they have a degree, like you. Oops.
I just got done working with Raybestos engineers on a clutch project and they totaly screwed it up. They did not take the information and tech that I gave them because they know better. After all, they have a degree, like you. Oops.
Friday night in Baytown, TX..We plan on being there of all goes as planed. so come on if you comen.:driving:
That plus not everyone has the ability to pull the equipment they need to make the shaft out of thin air! And heating any kind of metal what so ever makes it stronger true.....but it also makes it brittle so if there is any kind of play what so ever it makes it that much easier to snap off!
Well, shit, I guess I was wasting my potential. Time to go back to good ol' redneck engineering. After all, the fact that you have to even fix a trans used at a mere 3 times it's designed ratings shows those dumb ol' Allison engineers screwed it up big time, eh?
I've got news for you - those billet shafts that cost $600+ are heat treated. No steel, no matter how bling, will have strength for crap if it isn't. You can take the finest 300M, but without heat treat it will be barely stronger than 1018 mild steel, and much weaker than a stock shaft. The whole point of all the cool alloying in those high strength steel alloys is to allow them to be heat treated to higher levels. Yes, steel becomes more brittle as it gets harder, which is why you don't make it too hard. There is actually a science and, dare I say it, engineering that goes into it.
First of all engineers are the cheapest people I have ever meat. I hang out with many of you guys. You pinch pennies even if it cost you a grand to make something on your own that would have cost you less to buy. And, your homemade crap never works. Show me your 6 speed conversion. You can't because it doesn't work and you can't make it work.
If I built you a trans you would pick it apart and bitch about every little thing. If you built it your explanation would be " they will have quirks "
Instead of doing the usual engineer B/S with big words and pictures; put your idea behind a 1,000 hp truck. Do it a bunch of times.
You sound just like killer bee. You live in the same place. You may even be him. You preach the same crap.
i noticed something in my truck today that made me think F'N engineers! Why the hell are my cup holders right in front of the speaker on my back doors? wtf!
You know, I think I have you figured out. You're insecure. Somebody knows shit you don't, and it pisses you off because your supposed to be the super guru. You don't like what I'm spewing? Then prove me wrong. Explain in detail WHY it won't work. You won't because you can't. Once your lack of knowledge about anything other than trans building starts to show you resort to flinging shit like a petulant chimpanzee.
The cup holders are placed there so the ultrasonic waves from the speakers actual have a cooling affect buy removing heat from the air and pushing cooler air over your drink. :spit: