When to tow in All wheel drive or 2 wheel drive?

I have a 2009 chevy trailblazer (5200lbs towing with weight distribution hitch) that is capable of pulling my 2720SL (3500lbs) so should be fine. The question I have that I would like some other opinion on is this. With my truck I can tow in 2wheel, all wheel , 4 high or 4 Low as options and wondered if there would be any safety advantages in towing in all wheel drive on wet roads (raining) and say 2 wheel drive on dry roads? Or would anyone suggest that I should always drive in all wheel drive (auto) or two wheel drive?

Having a similar setup on our Jeep, all I can say from experience is that having it in all wheel drive mode helps prevent wheel spin when accelerating from a stopped position on a wet road while towing. It also improves traction when hitting puddles, etc, so I commonly use it when the road is slick. On dry roads I leave it in 2 wheel drive for less wear and tear and improved fuel economy, although it shouldn't make much difference. Most 'all wheel drive' systems are 2 wheel drive most of the time, and only transfer the power if needed.

I don't have quite the same setup as you do, but I have a choice of 4 wheel or 2 wheel drive. I use it pretty much the same way with or without the TM...if the road is slick 4 wheel and if traction is good 2 wheel.

[rickst29]

And that's especially because you have the good sense to tow with a WDH hooked up. The Torque which the WDH creates to prevent sag on the rear tires of TrailBlazer puts weight back down on the front axle, so you're steering control is excellent under normal, dry conditions.

Switch to 4WD when the roadway is wet, or when you're on an extreme grade. (2WD saves a bit of gas. )

Thanks for the comments. I kind of thought that it would be good to put it in all wheel drive when the roads are wet and maybe a bit slippery. Your comments seem to reinforce this. I guess if you are paying for the all wheel drive option and it can make things a little safer you might as well use it the when things are a bit slick and not worry about a mile or two less per gallon that day! Thanks again.

When I bought my Durango I had a choice between "4WD" and "AWD". I was concerned about mileage, thinking that 4WD would give me 2WD most of the time, thus better mileage. FWIW the EPA numbers for both models were identical!

Given the type of weather/road conditions we have here (Front Range of Colorado) the AWD option works best becase we constantly have conditions where we go from pavement to slick snow/ice and back. The problem with 4WD is that designation typically means that the differentials are locked, so all 4 wheels turn at the same speed - a real problem if they can't slip a little.

So I tow and drive in AWD all the time. You have an interesting setup - I don't think I've ever seen a vehicle with a combination like that - AWD, 4WD and 2WD!

Originally Posted by Al-n-Sue

So I tow and drive in AWD all the time. You have an interesting setup - I don't think I've ever seen a vehicle with a combination like that - AWD, 4WD and 2WD!

I Think A Lot Of Chevy's Do That... I've Seen Some S-10 blazers With The AWD Option And I Have A Tahoe With The Same Set-Up

[Bill]

My Ford Explorer has a slightly different set of options. They are 2WD/4Low/4High/Automatic 4WD. The default, when you turn on the key, is Automatic, and I love it! Whenever we get in a greasy situation, whether related to rain, snow, sand, or gravel, we can feel the 4WD kick in and pull us through. Otherwise, it stays in 2WD, conserving gas. If any of your options include Automatic Anything, that may be the way to go.

It appears that you already know it, but I'll repeat - never tow in 4Low unless you are off-road or on icy stuff, and never tow in 4High if you are on hard pavement, wet or dry. It will break your 4WD.

Bill

Nearly all the comments have favoured all wheel drive, especially on wet or slick roads which is great. The other comment which got me thinking was the one comment about using the all wheel drive on EXTREME grades on dry roads. Thinking about this I realized that I have a steep driveway and if I try and back the trailer up in 2 wheel drive even on dry pavement, the rear tires spin so I am forced to put it in all wheel drive. So putting it in all-wheel drive makes sense to me on very steep grades even on dry pavement. Perhaps this will also split my 285 hp to the two axles separately causing less stress on the single axle/differential only under very heavy pulling. I guess it depends on what actual vehicle you have and how much the truck actually transfers the loading. However I would expect any shifting/transferring of loading/stress would be a benefit in this situation.

Along the same lines...what about the button on the end of the shifter. Some are called "Tow Mode" and I think changes the shift points on the tranny. Mine turns off the OD in the trans. My question is....do I leave the OD off all the time when towing, or just when climbing and/or when there's a little stress on the trans? I hope I explained that well enough.... I haven't towed with the Tundra yet, so just wondering how you all do it. Thanks.