Offroad Trailblazers and Envoys

Where have you driven your Trailblazer? has the information you need to modify your GMT360/70
for exploration and discovery of the unpaved areas in the world.

Check out our Articles below and join the forum!
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View the latest news posts and updates from ORTB.

Lifts / Suspension

Vehicle suspension maintenance information and lifting articles.

Wheels / Tires

Relating to everything wheels and tires.

Differentials / Axles

Look in here for information about drivelines and gearing.


Components built by members, and tips for your own fabrication.

Electrical / Communication

Batteries, wires, antennas, and buttons.


Stuck? We've got info to help you get out safely.

Utilities & Resources

Calculators, technical documents, and general resources.


Want to spend some time outside? You'll find info about that right here.


This section helps you find and resolve common problems.

Latest Forum Posts

I would regularly sleep in the back and being 6'3", removing the seat bottoms and head rests let me stretch out diagonally. I also like the [Go To Post]

Lone_Wolf wrote:I just want to upgrade to GT4 or GT5 but my tools and knowledge are minimal. What's easier or cheaper? Gears or axlesCheaper and [Go To Post]

Having done the removable seat mod allowed me to put my 6 gallon water containers right behind the seats, helping to keep that weight more centered in [Go To Post]