Overview of AWD Systems

[TiGeo]

I know this is old but the OP is really good and pretty accurate in terms of AWD system rankings. Years ago I didn't know much about different AWD systems. I think the best system is anything with a torsen center/lockable diff - LC/4Rummer Limited/Lexus/Audi.

Auto 4wd came in handy today as we drove through some heavy cells. 4auto in the Colorado works quite well.


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Have you ever driven a newer Haldex system? They work excellent. We have 5 Haldex and 2 Torsen in the fleet.

 

[MCompact]

I’m comfortable with RWD so AWD is not a requirement for me; I do like the AMG tweaked 4MATIC system in my C43 much better than I thought I would- probably due to the permanent 39:61 front/rear bias.

 

[nobb]

Interesting read, even if it was from a decade ago. Any system is a compromise between performance, cost, and fuel economy. I'd be interested to know more, or see discussions on:

1. Land Rover has not been mentioned. What I find interesting is although their systems are tailored more for heavy duty off road use, when using them in high speed AWD mode, can they be considered comparable to the tier 1 AWD systems? What other truck based systems are comparable? eg. Land Cruiser, 4Runner Limited, etc...

2. For truck based systems, how do the "Auto" mode for the various trucks compare? eg. F150, Ram, Silverado. My understanding is that these may react even slower than typical AWD systems in connecting the front driveshaft? How are they for highway driving in snow/ice conditions? Does the slow response time make them only marginally better than being in RWD mode?

 

[Skippy722]

Interesting read, even if it was from a decade ago. Any system is a compromise between performance, cost, and fuel economy. I'd be interested to know more, or see discussions on:

1. Land Rover has not been mentioned. What I find interesting is although their systems are tailored more for heavy duty off road use, when using them in high speed AWD mode, can they be considered comparable to the tier 1 AWD systems? What other truck based systems are comparable? eg. Land Cruiser, 4Runner Limited, etc...

2. For truck based systems, how do the "Auto" mode for the various trucks compare? eg. F150, Ram, Silverado. My understanding is that these may react even slower than typical AWD systems in connecting the front driveshaft? How are they for highway driving in snow/ice conditions? Does the slow response time make them only marginally better than being in RWD mode?

For 2, there are so many different kinds.

I know the Rams with the BW44-44 transfer case, those with 4x4 auto, use clutches but it's kind of a clunky system and really only applies power to the front once wheel slip has been detected.

Our Expedition on the other hand seems flawless, it'll dial in power incredibly smoothly and is capable of sending 100% to the front wheels if needed and is very quick to act on top of "predicting" wheel slip.... They claim within 1/3rd of a revolution of a wheel. It feels like it behaves identically to my AWD 2011 Durango I had, which was QuadraTrac-II aka full time AWD with variable torque split and torque vectoring.

 

[nobb]

Our Expedition on the other hand seems flawless, it'll dial in power incredibly smoothly and is capable of sending 100% to the front wheels if needed and is very quick to act on top of "predicting" wheel slip.... They claim within 1/3rd of a revolution of a wheel. It feels like it behaves identically to my AWD 2011 Durango I had, which was QuadraTrac-II aka full time AWD with variable torque split and torque vectoring.

Awesome, would be curious on the differences between the the different manufacturers. My next vehicle would likely be a compact truck since I'm not entirely convinced I need a full size. To my disappointment, there's only limited models that offer the Auto mode. Eg. Colorado/Canyon or the Tacoma Limited (but you'd lose out on the TRD features)