Split/Second

This is quite doable with the right car and the right track in Quick play.
I used the Hanzo FX350 as it is the fastest steady car (non autp-drifting) available. It also has very sharp handling, which is perfect for avoiding barrels.
Then just pick Storm Drain and start racing. Try to pass the trucks with ample manouvering space, it's not worth passing them when you don't have space to dodge barrels.
I got this and Fearless on my first attempt!

I went in quick play and used Storm drain speedway, the trick to this is to remember that you can take your time, the most important thing is to be careful. For this i used the corberetti slipstream. I only used this car because im used to it and i know how to drift in it well. Pick a car you are good with as opposed to one with a higher speed that your not familiar with.

You can get the convoy achievement and the sudden death one at the same time like i did if you do this right. Obviously the blue barrels dont kill you but depending on the strength of your car they could cause you to wreck. On storm drain the road is fairly wide so stay in the opposite lane as the truck and try to steer clear of the other racers. When they crash their debris can block your field of vision and ended up wrecking me several times. Occasionaly you can make it past a truck without it dumping red barrels but if you get stuck behind one when it does just slow down and avoid them, with the Corberetti Slipstream you will be able to accelerate fast enough to pass the truck easily.
This took me a few tries but keep trying and be careful and youll get it

This is a very easy, albeit tedious solution. From the Quick Match section choose the Storm Drain map and use a car with high acceleration. Once the game has started:
1) stay close to the first truck all the time and pass it right away only when the time is up.
2) Important once you have passed, stop immediately and be overtaken by 6 other trucks
3) when the seventh truck has overtaken you .. accelerate immediately and pass it, you will see that it will count as a second overtaking.

REPEAT ALL THIS PROCEDURE FOR ANOTHER 10 TIMES AND YOU WILL UNLOCK THE ACHIEVEMENT