Danny....I posted this over in the Class A forum where you asked this question the first time and there was no mention of the Blue Ox tow bar.
FROM CLASS A FORUM-
Danny......I've towed three different trucks now behind my Diplomat. We bought a new 2012 Silverado 4x4 last week and I just finished setting it up to tow.
Needed:
You'll need a good heavy duty tow bar. A very popular one that is made from aluminum is the Roadmaster, Sterling, All Terrain towbar. It will handle 6k and is a well made bar.
Roadmaster Sterling All-Terrain Motorhome-Mounted Tow Bar - 6,000 lbs Roadmaster Tow Bars RM-576.
I try to use the same brand base plates as the tow bar. Roadmaster is one of the biggest brands. They have three types of baseplates for your Hummer. I like their MX brackets because they have a simple attachment for the safety cables
Roadmaster Tow Bar Mounting Brackets / Base Plates. The safety cables on the All Terrain model are incorporated in the tow bar through built in channels. The MX brackets have a small plate with a hole on the bottom side that lets you use a locking link to quickly connect. If you order one of their tow bars, make sure you order the safety cable that works with the baseplate brackets you are buying.
You'll need to buy a braking system for a vehicle that size. I do all of my own installs and repairs and I was willing to pay for the best braking system out there, but it wasn't that simple. There are at least six or seven different styles of brake systems. Some are in a box that sit in the vehicle and push on the pedal. These were the first generation of brakes and are problematic. M&G makes a unit that attaches to your master cyclinder (one time installation) and uses your air brakes to operate. I have the SMI Air Force One system that uses my air brakes, but allows me to move it to a different vehicle if I buy a new one.
There are several that use a piston attached to your brake pedal and push after it gets a signal from it's controller. Some of these have the piston hidden and permanently installed and some you put in place on each trip.
There is another system called the Ready Brake which is a tow bar with a surge brake mounted to it. As you stop your coach, it pushes on the surge brake which in turn pulls a cable that is attached to your brake pedal. Many like the ease and simplicity of this system, but no one has ever been able to explain to me how well it works once your vacumn canister runs out of air and the brake pedal in the car becomes rock hard.
Lastly, you'll need to wire in brake lights. I've tried several ways, including the diodes. I now just like to add a second bulb to the OEM lense if there is room. On my new 2012, I went to the auto parts store and bought a couple of the new style sockets that are flat on the outsude and use the bayonet light bulb. It was a very easy/clean install because the sockets took up half the room and they have a foam seal that sealed them against the brake light housing.
You're looking at spending between a $1000.00 and $2000.00 to set up your HummerH2.
I've done the installs above on several vehicles. If you have any further questions, send me a PM and I'll give you my phone number.