rentral truck hit a height restrictor in IKEA

First and foremost, it is important to check the terms of the insurance you purchased with the truck rental, as well as your own motor vehicle policy, to see if you'd be covered for this event. I suspect that you'll be provided coverage to some extent. But without seeing the policies, I cannot advise. If there is coverage afforded to you, you must notify the insurance companies about the incident immediately. Also, if you receive any correspondence or lawsuit papers from IKEA or its representatives, you must forward that paperwork to the insurance companies so that a claims representative and/or lawyer can be assigned on your behalf. Regarding your second question, if IKEA brings a claim against you or sues you, one of your defenses can be that there was a lack of adequate warning about the height restrictor bar. This may not let you off the hook entirely but may serve to reduce your liability to the extent IKEA was comparatively negligent. I hope this helps.