If you turn on your rear diff lock, does the ECU activate the Haldex to fully engage?
Thanks Loz, so if your on soft ground by turning on the diff lock you engage the 4wd.
The reason for asking the question, is last week on a grass slope in the rain I could feel the the rear diff engage, and dis engage once I had good front wheel traction. When I engaged the diff lock it appeared to provide constant drive to all wheels.
The reason for asking the question, is last week on a grass slope in the rain I could feel the the rear diff engage, and dis engage once I had good front wheel traction. When I engaged the diff lock it appeared to provide constant drive to all wheels.
You must remember to dis-engage the diff lock as soon as you are back onto a grippy surface, otherwise you risk damaging drivetrain components!
The T6 4Motion is a part time all wheel drive vehicle. Just like most of it 2wd siblings, it is usually being propelled by its front wheels. The Haldex, essentially engages the rear axle, converting the vehicle front front 2wd to 4wd. It achieves this very rapidly just a fraction of a revolution of a wheel. It detects and reacts to a speed differential between axles. It disengages as soon as it feels both axles are turning at approximately the same speed. I am not up to date and do not know which version of Haldex the T6 operates with or if any electronic sensors from the ABS assist in its deliberations. Depending on the version results in how efficient it is and how smooth or partial in its execution.
The diff lock does not engage the rear axle! Only it is sited in the rear differential and locks both rear wheels together, preventing differential action. Perhaps, I am unsure how it is all put together in the T6 but that is all it does. Not all 4Motion vehicles have a diff lock It prevents one rear side or other from spinning aimlessly away under adverse conditions. Most of the time off road or unless very adverse it may not be necessary to engage. That need a little experience to judge when and when not to use it. For the most part the Haldex will look after most people most of the time. The diff lock just adds that little bit more. For instance when towing off road when off road when very slippery, particularly up or down steep slopes, more extreme conditions, negotiating cross axle conditions, that is where one wheel might wave in the air preventing traction.
Axle diff locks can compromise turning sharply. They have a tendency to push a vehicle on, causing understeer. With frequency of use one learns what the effect is on a particular vehicle. Basically, avoid deployment then if the surface has good traction. Haldex is a good compromise for most in many situations but it is not perfect and can be beaten. It may need a bit more activation of the accelerator peddle sometimes, to get it going. That is, deliberately causing the front to slip slightly so loosing traction, temporarily and so engaging the rear axle. Again a little experience and different makes and models of cars feel and behave slightly differently.
My preference would have been the Ferguson or Quattro concentric geared systems. Far better but very much more expensive and not many people would need want or afford the price. I do wonder if one could easily buy one of these for this vehicle. They are availavle from the likes of Quaife Gears but I am not aware if they fit our vehicles directly. They are not only better, in my opinion, than diff locks, but also better than Haldex. If I had more disposable cash I would approach Quaife or similar. One in each axle or even one in a transfer box. Its good to dream occasionally.
That will do for now, I can already feel the weary eyes blinking with my boring asides and scribbles must try harder to be more susinct.
The diff lock does not engage the rear axle! Only it is sited in the rear differential and locks both rear wheels together, preventing differential action. Perhaps, I am unsure how it is all put together in the T6 but that is all it does. Not all 4Motion vehicles have a diff lock It prevents one rear side or other from spinning aimlessly away under adverse conditions. Most of the time off road or unless very adverse it may not be necessary to engage. That need a little experience to judge when and when not to use it. For the most part the Haldex will look after most people most of the time. The diff lock just adds that little bit more. For instance when towing off road when off road when very slippery, particularly up or down steep slopes, more extreme conditions, negotiating cross axle conditions, that is where one wheel might wave in the air preventing traction.
Axle diff locks can compromise turning sharply. They have a tendency to push a vehicle on, causing understeer. With frequency of use one learns what the effect is on a particular vehicle. Basically, avoid deployment then if the surface has good traction. Haldex is a good compromise for most in many situations but it is not perfect and can be beaten. It may need a bit more activation of the accelerator peddle sometimes, to get it going. That is, deliberately causing the front to slip slightly so loosing traction, temporarily and so engaging the rear axle. Again a little experience and different makes and models of cars feel and behave slightly differently.
My preference would have been the Ferguson or Quattro concentric geared systems. Far better but very much more expensive and not many people would need want or afford the price. I do wonder if one could easily buy one of these for this vehicle. They are availavle from the likes of Quaife Gears but I am not aware if they fit our vehicles directly. They are not only better, in my opinion, than diff locks, but also better than Haldex. If I had more disposable cash I would approach Quaife or similar. One in each axle or even one in a transfer box. Its good to dream occasionally.
That will do for now, I can already feel the weary eyes blinking with my boring asides and scribbles must try harder to be more susinct.
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