[Gonzo]

No this is not a question about marriage.....

I understand how the AWD system works and when. My question is after it does detect slippage and engages how long will it stay engaged for?


I wonder as I know you don't the AWD engaged on dry pavement... this morning there were many dry and snow covered areas. I was turning on to streets a lot and believe the AWD was kicking in as it should then the pavement went quickly to dry without snow, and therefore no slipping.

I was concerened about the AWD system remaining engaged and doing damage while on dry pavement especially while turning.

Any thoughts?

 

[Eric L.]

If its on auto mode, then there isn't anything to worry about, since its not like you can make it FWD only anyways. If its on AWD Lock, depeding on the year, AWD will switch to auto at 6 or 18mph.

Yeah it kind of stinks that there is no AWD indicator light that comes on when all four wheels are driven. But then, if it needs AWD, conditions are probably slippery enough such that you shouldn't be staring at your guages anyways.

 

[njjoe]

Gonzo-

Damn good question. I have often wondered about that.

It must be ether time or distance-dependent. If it didn't have a disengagement delay then the AWD clutch would disengage almost as soon as it engaged, similar to the action of anti-lock brakes. That would be extremely ineffective.

Since the AWD clutch pressure is fully variable (0 - 100% engagement) the clutch engagement may be instantaneous at 100%, but the disengagement is gradual. The clutch will reduce the engagement pressure to something less than 100%, if slippage is not detected then the clutch pressure will continue to drop until it reached zero. This is a continuous process. However, if during that process slippage is detected the engagement pressure will increase until slippage ceases.

That is how I believe it works. But that is not necessarily how it does work.

-njjoe

 

[Gonzo]

I was thinking that if I took my foot off the gas prior to hitting the dry pavement that would cause the system to disengage... but who knows.

 

[njjoe]

I was thinking that if I took my foot off the gas prior to hitting the dry pavement that would cause the system to disengage... but who knows.

Gonzo-

That's a good idea. Regardless of how/when the AWD clutch disengages, letting up slightly on the gas prior to hitting dry pavement reduces the driveline torque and puts less strain on the transfer case.

-njjoe

 

[Gonzo]

I wish the MO had a better system... this isn't something I should have to think about while driving. Maybe I'm just being overly cautious.

 

[njjoe]

I wish the MO had a better system... this isn't something I should have to think about while driving. Maybe I'm just being overly cautious.

You and me both.

-njjoe

 

[GMTURBO43]

Don't think about it.

Leave it in auto and go. The system reacts very quickly - I'd guess you wouldn't notice a difference taking off in 'Lock' or not.