Hello -
I have a 2010 TL SH AWD. I commute ~100kms to work then home, daily, on bare, dry pavement.
My thinking is that if I turn VSA OFF, each time I drive, then I'm only turning 2 wheels instead of 4 wheels, and will improve my fuel consumption.
Is my thinking correct?
Will I do damage to the car if I drive with VSA OFF full-time?

 

VSA off does not turn off all wheel drive...you will still drive all four wheels with VSA off.

 

OK thanks for the quick reply.

It seemed like it turned the front wheel drive off:
The other day I was driving on snow (parking area). I turned VSA off and cornered with a little extra throttle. The back end spun out. So it seemed like I had no front wheel drive.

Are you aware if I can turn AWD off?

 

No you cant. You spun out because you were in snow. The car will never be fully RWD or FWD.

 

Vsa is what keeps your wheels from slippin' too much. I believe it is possible to turn off power to the rear wheels and have fwd only but long story short theres really no reason to do that other than dyno pulls.

Why do you want to not have awd all the time?

 

I just thought it would improve fuel economy, really. 2 wheels would use less, I think. If I could turn off power to two wheels - just for the commute - then I would.

 

The Honda Pilot does that by default (only FWD, with 4WD kicking in when the front wheels are slipping or when locked in 1st or 2nd gear). But as far as I know, the only way to force the SH-AWD into FWD is have it throw a code for the SH-AWD system which disables the rear wheels.

Edit: Thinking more about it - I wouldn't worry too much about the potential to get better mileage by disabling the rear wheels. Again, from what I understand, the rear wheels are only lightly powered when cruising. Something like 90% / 10% between the front wheels and rear wheels respectively. So disabling them at that low of a ratio wouldn't have much impact anyway. The front wheels would pick up the extra 10% at that point and all you'd save would be some slight mileage from reducing rotational parasitic loss from the rear drive train. If I had to throw out a number, I bet it would be <1mpg. Far less than a vehicle that has full-time AWD like a Subaru.

 

 

Nope, even if you did figure out a way to disable the connection to one set of wheels, the drive train will still be rotating when you're moving and the inherent drag will still extract it's fuel economy penalty. Just a nature of the beast.

What kind of mileage are you getting in your car? I ask because I haven't heard the AWD G4 TL models are all that bad regarding fuel economy.

 

And the car would still have the extra weight of the SH-AWD components, and the 3.7 engine. Both of which account for probably 90% of the extra fuel consumption relative to the FWD car.

 

The propeller shaft, rear drive shafts, and rear differential still turn (although unloaded) with AWD disabled so you still have some of the mechanical "losses" of the system.