You might remember the meaning of the character 辆 with this easy mnemonic:
I know the measure word for vehicles, but what is the measure word for carts (車)? Your car is so old, it only has one (一) door and looks like a down box (冂) with a homeless man (人) living in it.
Using mnemonics to remember the meaning of Chinese characters like has a huge impact on how long to learn Mandarin it takes.