How to determine class III or IV receiver?

I've read in many posts about people having the class III/IV receiver hitch.
BUT... How does one know what they really have? (Unless you Installed it yourself)
Basically, what is the difference between a class III and a class IV, In terms of visual aspects?

Thank you!

 

[Number4]

The cars came stock with either the 1 1/4" or 2" receiver. The 2" has the 7 pin or RV style electrical connector, the smaller is just the flat four pin. The 2" setup allows you to pull 7k of weight. Though I believe it varies on whether you have the V8 or V6. You can also look at your rear axle code. The 3.55 rear end should only have come with the 1 1/4" receiver. I don't know the axle codes off hand, I believe the 2", 3.73 gears is D4. But someone else would need to verify.

 

[Machine090767]

I have the 3.73 L/S axle, a 7 pin connector and a 4 pin flat connector, 2 inch receiver.

 

[thebrakeman]

It's not a "Class III/IV Hitch". It's a Class III/IV HD towing package. The 2" receiver that comes with the HD towing package is Class IV as far as it's capacity. But you can only have Class IV system if you also have the V8 and are using a WDH.

Base vehicle (no HD towing package) regardless of engine, has the Class II, 1.25" receiver, limited to 3500 lbs, 500 lbs TW.
Vehicles with HD towing package have the 2" receiver. There are not 2 different Class III and Class IV receivers.
It's a Class IV receiver. But if you are not using a WDH, and don't have more than 5000 lbs max tow rating, the vehicle is only Class III.

a. V6, HD-tow, w/o WDH, is a Class III system, 5000-5500 lbs max towing, limited to 500 lbs TW
b. V6, HD-tow, with WDH, is still a Class III system, 5000-5500 lbs max towing, but I think can handle up to 700 lbs TW.
c. V8, HD-tow, w/o WDH, is a Class III system. TW limited to 500 lbs, so you can't tow more than 5000 lbs even though you have more max capacity. You must have at least 10% on the ball.
d. V8, HD-tow, using WDH is the full Class IV system. 7000-7400 lbs max towing, and 700-740 lbs TW