Why do you need lockers front and rear?

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Mar 19, 2013 | 06:18 PM
  #46  
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Mar 19, 2013 | 07:48 PM
  #47  
Quote: Huh?
Didn't you just say you were a mechanical engineer? How do you not know what EE means? I find that a zero possibility.
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Mar 19, 2013 | 10:23 PM
  #48  
Lmao. Where did you get your engineering degree, Belford University? I've never met any engineer, P.Eng or otherwise, that was so confused. Your incorrect usage of terminology and grasping at mathy-sounding rationalizations is screwing you up.

Revving the engine has nothing to do with increasing the applied torque. The reason it works (which is circumstantial) is because the tires wear enough crap out of the way and finally grab. The rate at which this occurs is determined by how fast the crap shows up, and how much crap your tires clear. EG: stuck in mud.

Like McCaffery said, power distribution isn't static. The whole thing is about AVAILABILITY: differential gearing provides full availability to each output. A locker fixes this by effectively turning an axle into a single output. A wheel in ice or in the air becomes no different then your tires' sidewalls. You can think of this in terms of power distribution as a SINGLE wheel. The fact that there are multiple contact surfaces is a convenience to the driver. If you apply 100ft-lbs @ 100 RPM to a locked diff with two wheels on the ground, you get 100ft-lbs traction and 100 RPM. It you apply 100ft-lbs @ 100 RPM to a locked diff with one wheel on the ground, you still get 100ft-lbs worth of traction, and still turn 100 RPM.

With two lockers and a locked transfer case, The whole system operates as a single unit. All of the engine's torque can be applied at any point on this single unit because as one wheel has traction, there is resistance on the entire drive train. There's no math involved.
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Mar 19, 2013 | 10:38 PM
  #49  
Quote: Well I have a mechanical engineering degree, although I'm workin for and electrical company right now. So my engineering physics aren't that fresh
How long does it take to get a mechanical engineering degree? 2 years min? Because your last thread, you had stated you were 19 years old....... And you have a degree, and working at a company and your physics aren't so fresh???? I took college chemistry junior and senior year of high school, stoichometry, kilo jewls, etc... It's been 5 years since doing that and I still remember very clearly how to do it.... Sounds kinda like someone's isn't telling the whole truth of their knowledge
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Mar 19, 2013 | 11:10 PM
  #50  
Quote: How long does it take to get a mechanical engineering degree? 2 years min?
Up here two years gets you a college diploma - engineering program is a four year specialization with an accredited university. To get the title is four years relevant work + a final exam.
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Mar 19, 2013 | 11:14 PM
  #51  
Quote: Lmao. Where did you get your engineering degree, Belford University? I've never met any engineer, P.Eng or otherwise, that was so confused. Your incorrect usage of terminology and grasping at mathy-sounding rationalizations is screwing you up.
I didn't want to call the guy out but I seriously doubt he's an engineer.

Quote: How long does it take to get a mechanical engineering degree?
4 years.
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Mar 19, 2013 | 11:15 PM
  #52  
Quote:
With two lockers and a locked transfer case, The whole system operates as a single unit. All of the engine's torque can be applied at any point on this single unit because as one wheel has traction, there is resistance on the entire drive train. There's no math involved.
Exactly right. That's what I was trying to explain but you did it better.
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Mar 20, 2013 | 12:18 AM
  #53  
Quote: Lmao. Where did you get your engineering degree, Belford University? I've never met any engineer, P.Eng or otherwise, that was so confused. Your incorrect usage of terminology and grasping at mathy-sounding rationalizations is screwing you up.

Revving the engine has nothing to do with increasing the applied torque. The reason it works (which is circumstantial) is because the tires wear enough crap out of the way and finally grab. The rate at which this occurs is determined by how fast the crap shows up, and how much crap your tires clear. EG: stuck in mud.

Like McCaffery said, power distribution isn't static. The whole thing is about AVAILABILITY: differential gearing provides full availability to each output. A locker fixes this by effectively turning an axle into a single output. A wheel in ice or in the air becomes no different then your tires' sidewalls. You can think of this in terms of power distribution as a SINGLE wheel. The fact that there are multiple contact surfaces is a convenience to the driver. If you apply 100ft-lbs @ 100 RPM to a locked diff with two wheels on the ground, you get 100ft-lbs traction and 100 RPM. It you apply 100ft-lbs @ 100 RPM to a locked diff with one wheel on the ground, you still get 100ft-lbs worth of traction, and still turn 100 RPM.

With two lockers and a locked transfer case, The whole system operates as a single unit. All of the engine's torque can be applied at any point on this single unit because as one wheel has traction, there is resistance on the entire drive train. There's no math involved.
X3. Read this, and let it be settled.
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Mar 20, 2013 | 05:17 AM
  #54  
To confuse no4x4yet even more, when one wheel is on the ground not spinning, the wheel in the air is spinning 2 times as fast since it has to make up for the stationary one.
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Mar 20, 2013 | 08:23 AM
  #55  
Quote: I understand how diffs work. seems likes its better than most here. I wanna know how they transmit power.
The link I posted shows exactly how a diff works and transmits power to the wheels.
A locker simply locks the axles together.

Each wheel gets equal amounts of power applied.

You're making this far more complicated than it needs to be.
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Mar 20, 2013 | 08:40 AM
  #56  
Quote: Up here two years gets you a college diploma - engineering program is a four year specialization with an accredited university. To get the title is four years relevant work + a final exam.
Took me and everyone in my class roughly five years to achieve a mechanical, chemical, civil, environmental degree. That's from Michigan Technological University, where they do not **** around. After that you have to work under a licensed engineer for four to five years, when completed you can take an 8 hour exam to try and get your professional license. Unless you've received countless hours of in the job experience or taken the time to learn calculus, dynamics, thermo dynamics, and differential equations. You're not an engineer, and still have a long way to go. Just my two cents, cause I worked my *** off for my degree (civil/structural engineer) !
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Mar 20, 2013 | 08:59 AM
  #57  
Quote: Didn't you just say you were a mechanical engineer? How do you not know what EE means? I find that a zero possibility.
Its depends what you are relating it to. If EE means Electrical Engineering, it makes ZERO sense to my comment you quoated. Which is why I asked what you ment.

Quote: Lmao. Where did you get your engineering degree, Belford University? I've never met any engineer, P.Eng or otherwise, that was so confused. Your incorrect usage of terminology and grasping at mathy-sounding rationalizations is screwing you up.
I didnt realize this concept was so foreign when introduced it. I was confused which is why I am asking the questions. The fact that some people refuse to believe that braking, while not a great idea can help with an open diff says a lot.

Quote: Revving the engine has nothing to do with increasing the applied torque. The reason it works (which is circumstantial) is because the tires wear enough crap out of the way and finally grab. The rate at which this occurs is determined by how fast the crap shows up, and how much crap your tires clear. EG: stuck in mud.

Like McCaffery said, power distribution isn't static. The whole thing is about AVAILABILITY: differential gearing provides full availability to each output. A locker fixes this by effectively turning an axle into a single output. A wheel in ice or in the air becomes no different then your tires' sidewalls. You can think of this in terms of power distribution as a SINGLE wheel. The fact that there are multiple contact surfaces is a convenience to the driver. If you apply 100ft-lbs @ 100 RPM to a locked diff with two wheels on the ground, you get 100ft-lbs traction and 100 RPM. It you apply 100ft-lbs @ 100 RPM to a locked diff with one wheel on the ground, you still get 100ft-lbs worth of traction, and still turn 100 RPM.
Now your using terminology incorrectly. I didnt say the applied torque, just torque. Applied torque, thrust or POWER is the limiting factor.

Quote: With two lockers and a locked transfer case, The whole system operates as a single unit. All of the engine's torque can be applied at any point on this single unit because as one wheel has traction, there is resistance on the entire drive train. There's no math involved.
This is the simple explanation which I already know. This doesnt answer my question however.


Quote: How long does it take to get a mechanical engineering degree? 2 years min? Because your last thread, you had stated you were 19 years old....... And you have a degree, and working at a company and your physics aren't so fresh???? I took college chemistry junior and senior year of high school, stoichometry, kilo jewls, etc... It's been 5 years since doing that and I still remember very clearly how to do it.... Sounds kinda like someone's isn't telling the whole truth of their knowledge
NEVER did I say Im 19 cuz I am not.

Quote: The link I posted shows exactly how a diff works and transmits power to the wheels.
A locker simply locks the axles together.

Each wheel gets equal amounts of power applied.

You're making this far more complicated than it needs to be.
I know how a Diff works, open, locked and LSD. I want to know how any why they work as a system with the engine. Yeah I dont need to know this but I want to. It can only help.
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Mar 20, 2013 | 09:05 AM
  #58  
Quote: Took me and everyone in my class roughly five years to achieve a mechanical, chemical, civil, environmental degree. That's from Michigan Technological University, where they do not **** around. After that you have to work under a licensed engineer for four to five years, when completed you can take an 8 hour exam to try and get your professional license. Unless you've received countless hours of in the job experience or taken the time to learn calculus, dynamics, thermo dynamics, and differential equations. You're not an engineer, and still have a long way to go. Just my two cents, cause I worked my *** off for my degree (civil/structural engineer) !
It certainly is not easy. Maybe you can clear something up then. How is your knowledge on subjects not in your field? Im sure you can agree that engineering is a broad field with many different disciplines and those not in your field aren't as fresh in your mind.
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Mar 20, 2013 | 09:19 AM
  #59  
OK let me add to this mess...with the NP242 transfer case, it features Full-Time four-wheel drive, which allows the transfer case to act as an open differential between both axles. Will braking in this fashion magically transfer more power to one end or the other in an offroad situation?

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Mar 20, 2013 | 09:31 AM
  #60  
Quote:
Here's my question. Since the transfer case is locked and splits power 50/50 if the engine is sending out 100 ftlbs, 50 to the rear thanks to the locker and 50 to the front. Now the open diff splits power equally so both tires get 50ftlbs. Now all tires front and rear receive 50ftlbs, so what are the benefits of a locker front and rear?
Now you are contradicting your self because this ^^^ is your question that you posted. It has been answered. What don't you understand at this point?

The benefits of a front locker are that it makes your axle one unit so you have 100% of the engine's power going to both wheels. Not a 50/50 split. Also, if you have a locked t-case the then You do not have a 50/50 split of front and rear torque as you suggest in your question. That would only be the case if you have an open t-case. Think of it this way: if you only had one tire of a locked axle on the ground and that tire had 100% traction, and the one in the air obviously has zero traction, then your thrust would still be 100% of what your engine can put out.

You are confused because you've gotten your info from Wikipedia and you think that because an open diff splits torque, locked axles must also. Not so because a locked axle can apply the same thrust with one tire having traction as two, as long as the one tire indeed has traction. That would be impossible if there was a 50/50 torque split, wouldn't it?
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