Q. I read your comments about synthetic oil and how you use it in your vehicles. My question is, which option is better for the environment?

A. Oil: Synthetic or conventional, when disposed of properly, can be reused or re-refined into usable oil. One gallon of used oil can be turned into 2.5 liters of motor oil that meets or exceeds new oil standards. Some motorists using conventional oil still stick to the 3,000 mile 3 month oil change. Many people who use synthetic oil tend to follow factory maintenance recommendations. Depending on the car, this could be once a year. Fewer oil changes mean less waste oil. So, at the end of the day, it’s not the oil that’s most environmentally friendly, but how it’s used in the motorist’s vehicle.

Q. My wife and I liked the comfort and usability of a 2022 Volvo Momentum. I was surprised to find that as a base model some safety features were not included, especially braking Emergency with Pedestrian Detection and Lane Keeping Assist. Several publications have written that these safety features are standard on all models. The dealer told me that the reason was due to the shortage of chips. So my question is if Volvo intends to retrofit the missing features when the parts become available?

A. If features are listed on the window sticker but those features are inoperable due to a lack of chips, I understand that once the semiconductor chips are available they will be installed and activated. Not all security systems are standard on all models. According to Volvo’s website, systems such as front parking sensors, a surround-view camera system, and Volvo’s driver assistance system are optional safety features. It’s not just Volvo that has optional safety features. I reviewed a Mercedes Benz GLE, a very nice vehicle, but about half of the safety features were optional equipment.

Q. I need to buy new mats for my car. When I asked the dealer they suggested I just go to a discount store. Where can I buy car mats that don’t slip and look good?

A. Online parts retailers carry a selection of mats ranging from winter mats to custom designed mats. The first place I looked was CARiD.com and they had multiple styles and prices. Years before there were so many auto retailers online, I used GG Bailey for my own vehicle (https://www.ggbailey.com/), a company specializing in quality car mats superior.

Q. Recently my 2017 VW Jetta had its oil changed at a local store. A few days later, I noticed the store marked 0W-20 on the windshield sticker to remind me when I needed to make the next change. The owner’s manual says 5W-30 or 5W-40 should be used. Should I have the oil replaced?

A. If the oil that was put in was actually 0W-20 and not just a few checked in the wrong box, the oil should be drained and replaced with VW 5W-30 or 5W-40 oil. Volkswagen is extremely specific about the use of VW spec 502.00 oil. Castrol and several other brands now carry VW/Audi Euro spec oil.

Q. I received three responses from Dodge Service on how to tow my 2018 Durango Citadel with the ‘Trailer Tow & Skid Plate Group’, 3.6 V6 and 8-speed transmission. One person said towing in ECO mode, another said not towing in ECO mode and the third said towing in SPORT mode. The owner’s manual is vague and refers to a “tow mode”. Which selection should I use when towing my 5,000 pound trailer?

A. Based on owner’s manual, just drive in and let the transmission decide. Sport mode gives you a bit more steering feel and slightly higher, firmer rev-change points. ECO mode does the exact opposite and shifts faster (not ideal when towing a trailer). So you just need to drive without selecting other modes. I believe some models had a specific tow/haul mode, but if your Durango doesn’t, then select drive and just drive. To add to the confusion, Dodge also says you can manually select a gear position using the AutoStick shifter. Find the highest gear that gives adequate acceleration while avoiding frequent downshifts.

Q. My 2005 Nissan Frontier has 195,00 miles. The air conditioner runs on fan level 1 but with very little circulation. The air conditioning does not work when I go to level 2, 3 and 4. The heat works on all four levels but again, very little circulation on level 1. What could be wrong with the air conditioning?

A. There are basically four parts in this system, the switch, fan fan resistor, fan motor and relays, fuses and wiring. When the fan resistor fails, the fan will only run at high. The fan itself has been problematic on these trucks with rust in the water pan and binding the engine. I would look at the fuses (there are three) and the relay and ground circuit.

Q. I have a 2013 Dodge Charger r/t and recently the AWD, ABS and FCW lights have all come on. I changed the AWD module, but the lights are still on. I went to a local auto parts store and when they scanned the car they said there were no codes. Ideas?

A. From your description I would say that one of the wheel sensors is faulty. If the anti-lock braking system is not functioning properly, the body control computer will shut down the related systems. Reclassifying why there are no codes, it may be the scanner/code reader the parts store was using. Not all code readers can read body commands.

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