13 things car insurance doesn’t cover

Full coverage car insurance protects you and your vehicle in many situations, from fender benders and fallen tree branches to vandalism and theft.

But there are a surprising number of things most basic policies won't cover, like personal items in your car, roadside assistance, custom parts and collisions outside the U.S.

Here are 13 scenarios not covered by standard auto insurance and how you can ensure you're protected.

Not even full coverage will reimburse you for an oil change, tire rotation or getting new air filters. But you can often get a prepaid maintenance plan or a set period of mileage from your dealership, garage or a third-party provider.

It won't cover all the necessary tuneup work but, by and large, you'll get a better rate and know in advance how much routine care will cost. Some plans are transferable if you sell your vehicle.

Standard car insurance won't cover damage caused by routine wear and tear. So, if your transmission gives up, you're out of luck.

A mechanical breakdown policy, however, will cover parts and labor for repairs to the engine, transmission, drive axle, suspension, steering, brakes, HVAC and other systems. CNBC Select has highlighted Endurance and Olive for their coverage of mechanical issues. Endurance is known for its direct servicing of plans, so you don't have to worry about being transferred to another company for service. Olive stands out for its affordability, with plans starting at just $49 per month.

Comprehensive car insurance pays out if your vehicle is stolen, but not if someone breaks in and grabs your laptop, phone, purse or other belongings. If you have homeowners or renters insurance, though, your stuff is protected, whether it's at home, in your car or anywhere else.

One of our top picks for home insurance, Amica, offers optional replacement cost coverage so you can get reimbursed enough to buy brand new items without worrying about depreciation.

If you're a renter, Lemonade's renter's insurance policies let you schedule coverage for jewelry, bikes and other valuables, and includes discounts for bundling with the brand's car insurance.

You can generally let someone else drive your car without them being on your policy. This is for infrequent, one-off uses, though.

Typically, though, any licensed driver who lives with you — whether that's a spouse, a roommate or your teenager — needs to be on your policy or they're excluded from coverage. If they use your car and cause an accident, any damages won't be covered.

Roadside assistance can be a lifesaver if you run out of gas, get a flat tire, or lock your keys in your car. But most car insurance companies charge extra for those policies.

However, there are a few that include it in their policies. Lemonade auto insurance is one of them, and comes with free nationwide roadside assistance for towing, winching, jump starts, tire changes and lockout services. You can even initiate a request and get real-time progress from your mobile app.

And, there's a chance you might have roadside assistance already. Some credit cards include it, like the Chase Sapphire Reserve, which includes coverage for up to $50 of assistance as many as four times per year for towing, battery assistance, tire changes and lockouts. While it does have a $795 annual fee, this card does offer premium travel benefits.

You could also get coverage through joining a travel club like AAA. Membership prices can vary by region, but include discounts on other travel purchases like hotels.

Lastly, you could get roadside assistance from an extended car warranty. Autopom offers roadside assistance coverage with all of its policies, available 24/7.

No matter what state you live in, your car insurance is valid across the U.S. Once you cross the border, however, it's a different story. Many providers extend coverage into Canada, but Geico is one of only a few that offers liability coverage in Mexico that is comparable to what you'd have at home.

Dairyland issues policies in 39 states, but only California drivers get automatic coverage within 25 miles of the U.S.-Mexico border.

If you're a driver for Uber or Lyft, your vehicle is only covered by the ride-share company's insurance when you have a fare. And, your personal car insurance only covers you when you're off the clock. When you're on the app waiting to be matched with a rider, neither car insurance covers you.

Additionally, both Uber and Lyft have $2,500 deductibles, so you'd owe a large amount if you did need to file a claim with the brand's insurance.

That's where a ride-sharing endorsement steps in. This can cover damages to your car while you're waiting to be matched with a rider, and also help with compensating you for the difference between your policy's deductible and the company's deductible.

Progressive ensures you're protected when you're on the clock but haven't picked up a customer yet, and also offers a deductible reimbursement if your policy's is lower.

Depending on the issue, the garage's schedule and the availability of parts, car repairs can take days or even weeks to complete. Standard car insurance won't pay for a loaner car, but with a full coverage policy from Allstate, you can add a rental car reimbursement benefit and be covered for $30 a day for up to 30 days.

Most auto insurance policies only cover up to $1,000 for modifications, which is barely enough for high-end rims. State Farm has supplemental parts and equipment coverage that pays for custom paint jobs, stereos, lift kits, spoilers and other upgrades and aftermarket parts.

If you have a collectible ride, you'll need classic car insurance, which has stringent storage requirements and mileage limits but pays out based on a predetermined value. Available nationwide, American Collectors Insurance's Freedom Tier policy offers higher liability limits and more options for deductibles, plus up to $250 to relocate your car during a natural disaster.

If your four-legged friend is riding with you when you're in an accident, most car insurance companies won't cover their veterinary bills.

Pet insurance can help soften the financial blow that vet bills can bring. It can cover accidents as well as illnesses your pet may face, and some policies offer coverage for things like prescription medication and even alternative therapies to get them back to themselves.

We like accident and illness policies from Figo, since they offer customized coverage with the option for preventive care costs. And, Costco members may be eligible for a discount.

Damages caused by racing, joyriding or off-roading aren't covered by standard insurance, and most classic car insurance policies don't cover this, either. However, there are some specialty insurers that offer coverage for off-track events. Hagerty is one of them, as it provides coverage for physical damage track days.

If you're held liable for an accident, your insurer will only pay out to your liability limit. Anything above that comes out of your pocket, so, to protect your assets in a lawsuit, it's recommended to have liability coverage equal to or greater than your net worth. 

If you have a particularly high net worth, an umbrella insurance policy from American Family can ensure your assets are protected. American Family also has generous discounts, including bundling home and auto insurance.

Your car starts depreciating the moment you drive it off the lot. If you get into an accident that totals your vehicle, your insurer may not cut you a check big enough to cover the balance on your car loan or lease.

Gap insurance covers the difference and, while you can often get a policy from the dealership, rates from insurance providers are typically the most affordable.

Nationwide has gap insurance for cars up to six years old, twice the three years that most companies will cover.

At CNBC Select, our mission is to provide our readers with high-quality service journalism and comprehensive consumer advice so they can make informed decisions with their money. Every insurance guide is based on rigorous reporting by our team of expert writers and editors with extensive knowledge of insurance products. While CNBC Select earns a commission from affiliate partners on many offers and links, we create all our content without input from our commercial team or any outside third parties, and we pride ourselves on our journalistic standards and ethics.

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