Rooftop tent leveling is the equivalent of camper leveling. You would like your vehicle to be mostly level to avoid the tendency to roll to one side during sleep. Just two simple tools will do the trick: leveling blocks and a simple, small bubble level.
Rooftop tent leveling blocks
The first one is a camper leveler by Andersen: Amazon.com: 2-Pack Camper Leveler, Chock Kit | Andersen 3604 x2
Here’s a video on it:
Camper Levelers by Andersen Manufacturing | Product Review | Fast easy side to side RV leveling – YouTube
Small, portable bubble level
The camper leveler by Andersen helps to level your vehicle but you need a simple, bubble level to put on the dashboard: Amazon.com: High Precision Horizontal Bubble Cardan Level. Don’t leave this in a place that can get very hot.
You will need to calibrate the bubble level before you go on a trip. Put your vehicle on level ground and then put the bubble level on your dashboard. The position of the bubble may not be in the center because your dashboard might not be level. Take a picture of the bubble position or mark the center of the bubble on the device. That bubble position is your target at the campsite.
There is a good chance that temperate might be a problem for your bubble level. If your bubble level gets wrecked due to temperate or sunlight, then use a bubble level app for your phone. Calibrate that before you go on a trip too.
The Bubble Level app at Google Play:
There is a version for iPhone too: Bubble Level for iPhone on the App Store.
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