Even a vehicle that looks rough and tough may not actually be ready to take onto dirt roads. This isn't about what tires you have or about doing a quick pre-trip inspection, it's the overall condition and safety of the vehicle and it should be checked over long before you hit the trail in case repairs are needed.
- Is your battery in good condition and secured properly?
- Are your engine belts strong with no signs of damage?
- Are your suspension bolts tight and bushings in good condition?
- Any signs of loose U-joints in your drive shafts?
- Does your vehicle shift properly in and out of 4wd?
- Any excessive play or noise in your wheel bearings?
- Do your brakes work correctly and, in the case of drum brakes, are they adjusted?
- Any excessive movement in your steering wheel?
- Any major fluid leaks?
- Any brake lines, fuel lines, or anything else hanging down where they could get snagged and damaged?
- Is your exhaust and muffler secure?
- Do you have recovery points? http://bc4wd.ca/meet-your-rig-tow-points/
- Do you have enough tread on your tires, and is there any damage to them?
- Is your scheduled maintenance up to date (especially tune ups, belts, and other wear items)?
- Is your vehicle reliable?
If the answer is no to any of these questions then you have no business venturing off the pavement. This especially goes for unreliable or untested vehicles. Nobody wants to spend all day sitting on the side of the road as you monkey with your truck when you either know it's not reliable or you just finished a repair or modification but didn't take time to test it before heading out.
If you need help ascertaining the condition of your vehicle and don't have a friend or mechanic you can trust then I suggest contacting a local 4x4 club and asking if someone would be willing to teach you the basics of checking over your rig.