CAR DOCTOR Q&A
Q. I work in the automotive industry in China and Recently we have had inquiries to import the 6.4L Jeep Rubicon 392. As they are still not available for sales in Chinese market, I have to take a look at the possible selling price to assess potential risks. As usual I went for competitive models for their prices. However, I couldn’t find one that matches at least two criteria among engine power, vehicle size, brand image, off-road capability, price, etc. So it’s interesting to know: What model(s) in the US market is regarded as the competing one with Jeep Rubicon 392? Considering a price of nearly $100,000, what kind of consumers are buying this high horsepower Jeep? If they are not price sensitive buyers, why not go for the Mercedes Benz G series? If they are, why not Bronco which you have mentioned several times in previous columns? If a competing model is not found, maybe it means Jeep 392 really has a unique positioning and targets a niche market? What do you think?
A. You are correct there is little that can compete on an even playing field with the 470 horsepower Jeep Wrangler. Yes, there are high horsepower SUVs such as the Porsche Cayenne Turbo GT at 631 horsepower, Lamborghini Urus at 641 horsepower and even the 707 horsepower Dodge Durango and Grand Cherokee Trackhawk. Although none of these vehicles are quite like the Wrangler. Recently Ford introduced a Raptor version of the Bronco which at 418 horsepower and 440-pound feet of torque, could be considered a true competitor. The 392 Jeep Wrangler, Hellcat models and other highperformance vehicles are all halo vehicles. They are really designed to bring excitement into the brand. Unlike most people who buy one vehicle, the buyers of these vehicles are typically wealthy business types, celebrities and highly paid sports professionals and buy them as just one of their fun vehicles.
Q. I have a simple question but get conflicting answers, how often should tires be rotated?
A. Most vehicle and tire manufacturers recommend tire rotation at 8-10,000 miles. Tire rotation is also a good excuse to check brakes, suspension and give the undercarriage a quick look for problems. That being said, on my own cars inspect the tires each month when I check the air pressure. If the tires are wearing evenly, I tend to not rotate them.
Q. I have a 2017 Subaru Outback with an Electronic Parking Brake. I have 45,000 miles on it and I need to replace the rear brake pads. Can I retract the rear brake pistons manually without having to use a scan tool and if so, what is the proper procedure? There is contradictory info about this on the internet. Also where do you get your information?
A. For the most part I use AllData as a technical database. AllData buys repair information directly from the vehicle manufacturers. According to what AllData/ Subaru: perform the following replacement procedure if the Subaru Select Monitor cannot be used. Remove the disc brake assembly and the pad - disc brake rear. Remove the bolt securing the lower side of the support rear disc brake, loosen the upper side bolt, and then slide the support - rear disc brake upward and hold it. Secure the disc brake assembly and push back the piston using a suitable tool. If you do a fair amount of work to your vehicle AllData also has a DIY version of their product which is quite reasonable priced.
Q. There has been much written and mentioned about Top Tier Gas (BP, Valero, Conoco, Mobil etc.) that regardless of the octane, they all offer better detergents and gas quality than non-top tier. Has it been shown that gas from those top tier stations help and outperform gas from stations such as Speedway, Marathon and others that are not TopTier? Does using a non TopTier in a pinch hurt the engine? Also, with today’s engines, if they don’t require Premium, does adding it boost the cleaning, effectiveness and longer lasting for the engine? Do today’s engines need any type of “boost” or cleaning to keep them running well?
A. Several years back, AAA has performed extensive testing comparing TopTier to non TopTier gas and found definite benefits of using TopTier gasoline. Yes, some gasoline manufacturers add additional cleaning additives to premium grades of fuel, but using higher octane fuel in a car that doesn’t require it is just a waste of money. Regarding skipping a tank or two and using non TopTier gas won’t harm the engine, in fact adding TopTier fuel will clean any deposits that accumulated from using fuel without as much cleaning additives. You can find the report here www.aaa.com/AAA/common/AAR/files/Fuel-Quality-Full-Report.pdf
Q. I own a 1998 four-door Nissan Pathfinder SUV. At first one of the back doors failed to open and now both doors do not open. The locks sound like they’re activated (open/lock) but they still do not open. Is this a problem that a car service center or locksmith can fix? Will finding parts be a problem, perhaps a junkyard? The car runs well otherwise, any advice would be appreciated
A. This is fairly common for the door lock actuators start failing one at a time as they age. The best method to conform this is to take the door panels off and inspect the mechanism. Although I have seen some shops use a borescope and peak down into the door to see what is going on. A locksmith or any qualified repair shop can repair this issue. Regarding parts, I would aviad salvage yard parts, since they may be in similar condition as your car. There are aftermarket parts which are about half price of the factory parts and considering the age of the vehicle may be more readily available.
Q. I enjoy reading your column each week. Recently a 2019 Subaru owner wrote in about an ongoing fail to start with dead battery situation unresolved by the dealer even after intervention by Subaru USA. I have 40 years in the retail automobile business I have encountered many anomalies. Although I have no experience with Subaru I do have a suggestion. Some years ago as the General sales manager at large dealership our service department encountered a like problem. It turned out her car was garaged so the owner always left the key in the ignition. The vehicle was structured such that some systems continue to draw electricity even if the key was in the ignition in the off position. Just a shared though from one professional to another.
A. Great reminder and it even get more relevant. Today with pushbutton start systems and proximity key-fobs even just leaving the fob in the cupholder or hanging on a nearby wall can keep the car from completely shutting down all of the electrical systems. Thanks again for the reminder.