Which PUBG vehicle can go the farthest without running out of gas

Sadly there is no "practice mode" available to the public yet, although there are custom matches.

In order to create a custom match you must be verified by PlayerUnknown, which will most likely only happen if you are either a streamer or company that would promote the game.

You can join a custom match by clicking on "custom match" after hovering over the play butten in the top right. Custom matches do not count towards your rank so it doesn't matter if you die right away while you're testing your fps. Even after you die you can still spectate the players and test your PCs performance that way.

There is a reddit analysis video that goes more in depth. But he posted the stats below it as well:

• Circle 1 Length - 4550m Damage - 0.4% Survive for - 4:10 Travel time - 5:00
• Circle 2 Length - 2970m Damage - 0.6% Survive for - 2:46 Travel time - 2:20
• Circle 3 Length - 1480m Damage - 0.8% Survive for - 2:05 Travel time - 1:30
• Circle 4 Length - 740m Damage - 1% Survive for - 1:40 Travel time - 1:00
• Circle 5 Length - 360m Damage - 3% Survive for - 0:34 Travel time - 0:40
• Circle 6 Length - 175m Damage - 5% Survive for - 0:20 Travel time - 0:30
• Circle 7 Length - 90m Damage - 7% Survive for - 0:15 Travel time - 0:30
• Circle 8 Length - 40m Damage - 11% Survive for - 0:10 Travel time - ~

As of 26-10-2017 there was an update changing the damage to be increased the further away one from the safe-zone circle is. Meaning this information is no longer correct.