ATRAC damage, discussion.
- Thread starter zimm
- Start date
proper4wd
Expedition Leader
As I explained I agree that at the limits of torque application, the locking differential has a greater propensity to break parts. However, over a lifetime of varied usage the traction control system will place a lot more wear and tear on items like differentials. The spider gears in the average open diff used in a traction control system are not designed for infinite service life when asked to transfer that much torque between wheels.
Capt Jon
Observer
The strain on the axle will always equal the difference between the force applied at the differential and the force required to turn the wheel. Thus if ATRAC is forcing the loaded wheel to turn, then it is applying as much strain as a locker. Maybe I am not explaining it well, but there is no way to apply more strain than it takes for the wheel to turn. If all four wheels are off the ground, the differential may be applying the 16,000 lbs of torque menioned above, but there is zero strain. The strain/load/ whatever you want to call it, will always be limited by the traction. If the wheel will not turn, either system will break the axle if it applies enough force. If the wheel does turn, then both are applying the same force.
proper4wd
Expedition Leader
Yes, however in order for the differential to transfer the amount of force necessary to turn the loaded wheel, the traction control system must apply an equal resistance to the non-loaded wheel by applying the brake. You have now doubled the amount of total resistance in the front axle, requiring the engine, transmission, transfer case, front driveshaft, and front differential to transmit twice the force.
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upcruiser
Perpetual Transient
This has been an interesting read. Being new to Atrac myself I had been wondering specifically what kinds of stress it would be putting on the drivetrain. It has been my go to setting in the FJC and I have been really impressed. I use it in a similar style to how I try to drive anyway, more along the lines of slow as possible, fast as needed. What I have found is that even with a momentary loss of forward momentum it would almost always find traction and proceed. The feeling that you get in the drivers seat is a bit unusual at first due to the sounds and almost unnatural way the system finds traction. It is damn impressive though. In tests I have done on loose surfaces and wet rock, Atrac vs locking the rear diff has been easily advantage Atrac. It seems to more than make up for the lack of articulation in an IFS rig. While not as seemless in its application of traction as say an LR4, it works remarkably well.
Thats not really what the conversation is about but it has made me wonder a couple of questions. First off, is the Atrac in the FJC's different from the 100 series? Does one function better or worse than another? Secondly, are there many documented cases of drivetrain failure due to Atrac? Would like to read about the instances and variables that could lead to drivetrain abuse with the system.
Thats not really what the conversation is about but it has made me wonder a couple of questions. First off, is the Atrac in the FJC's different from the 100 series? Does one function better or worse than another? Secondly, are there many documented cases of drivetrain failure due to Atrac? Would like to read about the instances and variables that could lead to drivetrain abuse with the system.
also I think most manufacture's are going with some sort of traction control instead of lockers; These guys spend millions on research and development; so I really do think they know what they are doing. Now FJ's (older ones) did not have a really good ATRAC like the new 4Run or LC have now. I know Scott is getting lockers in the LR4 and would love to see a camparo of one with and without the lockers! same tire, same PSI, etc but also same year truck! The new systems are very good! I'm not saying lockers don't work but you have to take into consideration the cost or the product and install etc. Lots of us don't have that kind of money; so you either go with a old truck that needs the lockers or a new one with the fancy electronic gizmo's. I'm not an expert but I feel that if a vehicle manufacturer is putting out a product today that is being presented as a 4wheel drive what would you do put in a locker? or a fancy sophisticated traction control?
Douglas S.
Adventurer
I'd go with the locker, just as OEM's choose to do on the more rugged 4x4 models (Rubicon, 7x Series Cruisers, Y61 Patrols, etc.). Traction control systems are better for people who don't understand how their driveline works (the majority of 4x4 owners fit into this category) so it's a better choice for most models.
I Leak Oil
Expedition Leader
Adam is right about differential wear. Side gears and spiders, cross shafts don't run on bearings but use bushings or the castings themselves. When one wheel is braked and one spins, those components all turn relative to the braked shaft, and turn fast. This generates heat and accelerates wear.
Signifacant or not depends on how much it's done. Something to consider.
Signifacant or not depends on how much it's done. Something to consider.
no way with the aded cost to manufacturer. You know much work goes into these programs for traction control?? Just look at the evolution of ATRAC from the first being offered in trucks. Ford actually bought Land Rover for this technology which is being used in the ford explorer etc. a few years back. This stuff is mucho money! It would be easier and cheaper to just throw in a locker. Now I do understand the locker is stronger and probably better certain instances but traction control can be used in much more areas
ask anyone who had a tight locker in their vehicle- its damn near scary when the locker locks up on you as your doing 30 around a turn on a wet road.
E- lockers and air lockers bridged this, but how many e lockers were factory provided? Not all that many. In addition, they had to program in speedo readings to turn it off under certain conditions.
adding lockers requires assembly line work- or at least to stock two different parts. For mass produced vehicles, electronic traction control is safer and cheaper to implement. I'd take atrac over a rear locker/posi anyday, because it would provide me with more ability up front.
E- lockers and air lockers bridged this, but how many e lockers were factory provided? Not all that many. In addition, they had to program in speedo readings to turn it off under certain conditions.
adding lockers requires assembly line work- or at least to stock two different parts. For mass produced vehicles, electronic traction control is safer and cheaper to implement. I'd take atrac over a rear locker/posi anyday, because it would provide me with more ability up front.
Douglas S.
Adventurer
No. The per unit cost of adding lockers to an individual vehicle is much much higher than traction control. A traction control program needs to be developed and updated, yes, but the cost can be spread out over thousands of units and the cost to add the system to individual vehicles is immaterial.
I Leak Oil
Expedition Leader
Vehicle manufacturers are generally in business to sell to the masses. Traction control is easier to use and somewhat seamless and mindless for the average buyer. To try and rationalize that the system is targeted toward "us" is delusional.
proper4wd
Expedition Leader
Including "ATRAC". Just Toyota's attempt at increasing the appeal of what is a standard feature on most other 4wds.
njtacoma
Explorer
Perhaps this is off topic, if so I apologize.
What about sand? I recall many years ago when the first traction control trucks came out it was necessary to turn them off in sand, because they tended to cause you to get stuck with the braking etc necessary for the system to work.
Does the Atrac or any system do better with that now? Is it currently a non issue?
Just curious.
What about sand? I recall many years ago when the first traction control trucks came out it was necessary to turn them off in sand, because they tended to cause you to get stuck with the braking etc necessary for the system to work.
Does the Atrac or any system do better with that now? Is it currently a non issue?
Just curious.