Will my car’s new battery require adding water?

John Paul, AAA Northeast's Car Doctor, answers a question from a reader confused about a recent battery purchase.


Q. I recently purchased two Duralast Gold car batteries. They both have removable caps to check the water level. I thought I would be replacing the old batteries with sealed maintenance free batteries, yet the caps come off. I had a hard time finding replacement batteries, so I purchased these two. The auto parts store told me that these batteries should never require adding water. Can you tell me if that’s true, and if not, what type of maintenance do I need to perform with these?

A. Once upon a time all batteries required water to be added. In fact, checking the water level was standard procedure during oil change service. Today, most batteries are maintenance free. Some batteries are sealed and some, like the batteries you purchased, have removable caps. During the life of the battery, most people with never added water to their car’s batteries. Since your batteries have removable caps, there’s certainly no harm in removing them and adding water (distilled only) if the fluid level is low. If you are adding water periodically, suspect that the charging system is overcharging the battery and “boiling” off the water. If this is the case have the charging system evaluated.


Q. My wife just purchased a 2021 Volvo XC40 T5 R Design. We have been told that we can use regular gas in this vehicle. Exactly what grade of gasoline should we be using for this vehicle?

A. Fuel requirements are typically listed in two ways. The fuel that is required and the fuel that is recommended. In your particular model, the XC 40 T5 Volvo requires premium fuel (91 octane or higher). This applies to all T5, T6, and T8 engines, and recommends 93 octane fuel for optimal performance and fuel economy. Volvo recommends (not requires) premium fuel (91 octane and higher) for T4 engines. Volvo goes on to say that engine reliability should not be affected as long as 87 octane fuel or higher is used. In the case of your 2021 Volvo XC 40 T5, you should be using fuel with an octane rating of 91 or higher to prevent engine damage.

Q. How do I know if a used car I’m considering buying was involved in a recent flood?

A. Here are a few thing to look for. Inspect the car thoroughly — look for rust stains inside the car, especially around seat brackets. Does the car smell like mold/mildew or does it smell like someone is trying to cover something up? Look in the trunk under the spare tire. On an SUV, lower the spare tire and look for mud and debris. If the spare tire looks like it was just steamed cleaned, be suspicious. A spare tire that has been under a vehicle for a few years should be dusty — not caked with mud nor spotlessly clean. Look for water in the headlights and taillights. Open the hood and look for water stains, mud, and dirt in the nooks and crannies, like the alternator, cooling fan, and other surfaces. Check fuse boxes for signs of corrosion. Recent rust on unpainted screws indicate moisture. Check all the fluids — if they are milky colored, this could indicate water contamination. On a warm day, if all of the windows have condensation, this could indicate the interior has been flooded. Finally, when in doubt, have a good repair shop inspect the vehicle before you purchase it. And remember what mom said, if the price looks to good to be true, it probably is.


Q. The headlights are clouded up on my 17-year-old Infinity. What should I do?

A. You have a couple of options. The cheapest and sometimes the most effective method is to have the headlights cleaned. You can DIY it with some kits. Some use a buffing wheel that attaches to a power drill, others use a series of very fine sandpapers and then a polishing compound. You can also have the lenses professionally cleaned (about $100-$125). Finally, you can replace the headlight assemblies with a quality aftermarket part.

John Paul is AAA Northeast’s Car Doctor. He has over 40 years of experience in the automotive business and is an ASE-certified master technician. E-mail your car question to [email protected] Listen to Car Doctor on the radio at 10 a.m. every Saturday on 104.9 FM or online at


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