[RichardBondMan]

I know some "dualie" trucks are 4 wheel drive but are all dualies 4 wheel drive? Is there a definitive way to determine if a vehicle is a dualie without seeing the 4 wheels on the back, i.e. such as 3500, etc.

[CaptainRich]

I know some "dualie" trucks are 4 wheel drive but are all dualies 4 wheel drive?

No.

To be a dualie, there are "Dual's", i.e.: four across the back axle.

But that doesn't really make it a 4WD.

Yes, four tires on dualies are driven: the four on the rear.

But the more common reference to "4 Wheel Drive" is to have the rear axle driven AND that the front axle be driven as well, through a transfer case on the vehicle's transmission.

Is there a definitive way to determine if a vehicle is a dualie without seeing the 4 wheels on the back, i.e. such as 3500, etc.

If you don't see four on the rear axle, unless one fell off, it's not a dualie!