MudRunner

I got the achievement on the level Grizzly Creek at the spot you can see on the map. Right before the gas station on your left, there will be downward slope, that ,if you hit it at full speed, will give you enough speed boost to unlock the achievement.

I used a Western Star 6900XD truck fully loaded with small logs.

This is for those of you without the paid DLC and will be detailed enough that even those new to the game should be able to follow along. Download The Ridge DLC. Start a Casual game on The Ridge with the C-4310 (or whatever truck you prefer that can use a crane). Before doing anything, check the map. There are four Scavenge locations that are visible. Check the one on the far left (South of the Western Lumber Mill) to see if it has 4x Short Logs, if not check the one to the North East near the river (just south of the island with another Scavenge location). If neither of these do, hit and restart. Keep restarting until one of these has 4x Short Logs (you can make any of the Scavenge locations work, but these are the fastest/easiest to get to). Once you've got the 4x Short Logs to spawn strip your C-4310 and attach the Crane Support, Log Carrier With Crane, and the Short Log Trailer. Head out and pick up the Short Logs with the crane (don't forget to use the Advanced Menu to Turn and then Push the Anchors so you don't tip over). Pack up the four logs into the trailer. It's very picky if you haven't manually loaded logs before. Get them all into the trailer and then hold to put the crane away, then Push and Turn the anchors back into position. Then make sure your engine is running (if not hold for a second). Then go into the Advanced Menu again and use the to select the green dots on the logs. A green box will appear on the trailer and will allow you to pack them into a full bundle by holding . Haul your load back to the starting area. When you get back to the main drag open the map and switch to one of the C-65115s (it spawns two on the main street). Take it to the garage and strip the attachments off and put on the Log Carriage. Drive it back to the main street and park it to the side of your C-4310. Switch trucks again and use the Advanced Menu to Drop Load which unpacks the logs back into the four separate logs. Use the crane to move the logs into the C-65115. Switch trucks and pack up the logs like before. Keep the gearbox in Auto and head out. Turn right to stay on the main road that runs counter-clockwise around the island. Hold down and try to stay on the road. If you crash and disable your truck use the to force quit the game and load it back up. You can try it again from the last auto-save. You should pop the achievement after just passing the road to the Scavenge location. If you get all the way to the Fuel Station without it popping, turn around and try to get it going the other direction. Hope this helps!