Reducing oil consumption on higher-mileage engines may be easier than some service personnel realize. Saving cash-strapped motorists the cost of an engine overhaul may boost their loyalty. It may even earn you some new, long-term customers. Some service personnel believe that all motor oils are the same.
What's more, they dismiss all specialized automotive chemicals as “snake oil” or attempts to provide the proverbial “mechanic in a can.” However, my experience—and that of many other technicians—is that all motor oils and automotive chemicals are not created equal. Experimenting with various oils and “professional” additives may be as beneficial to your customers as it has been to those at other service facilities. If you never try anything new, you'll never know if you can exceed customer expectations by using the proper chemicals and/or motor oil.
Remember that when the piston slides downward inside the engine, healthy piston rings skim motor oil from the cylinder walls. Then this oil harmlessly runs back into the crank-case. But piston rings may stick due to age or neglected oil changes. To grossly simplify, sticking rings don't skim oil as effectively as healthy rings do, leaving excessive oil in the upper cylinder area. Then the engine burns off this accumulation of excessive oil, increasing oil consumption.
Mind you, sticking rings is only one of many potential causes of increased oil consumption on a higher-mileage engine. That said, however, circulating a professional-grade ring-cleaning chemical through the engine may free those sticking rings. Techs who advocate these chemicals have their favorites; I've had success with BG Products' No. 109 piston ring treatment (www.bgprod.com). Friends of mine who specialized in Honda work referred me to this chemical. At their recommendation, I ran it in an engine for 15 minutes or so prior to changing oil.
Or, I poured it into the engine and drove the vehicle for two miles before changing oil. In each experiment, I installed the same brand and viscosity of oil as that which the car owner had been using. Then the car owner would monitor usage as closely as possible. Typically, using the No. 109 treatment reduced oil consumption. Sometimes it took two consecutive applications to notice an improvement. But in many instances, the procedure reduced oil consumption 50 percent.
Now suppose money is tight and your customer really depends on his or her car. If so, then reducing oil consumption from a quart every 800 miles to a quart every 1,600 miles is definitely a big deal. Several service managers told me that reducing oil consumption helped convince customers to keep cars longer.
When their financial situations improved, they ultimately spent more money at those shops on routine repairs and maintenance. So ultimately, the ring-treatment chemical earned the shop more repair work. I happen to favor Mobil 1 synthetic motor oil. In some cases, just switching to synthetic oil (same viscosity) has reduced oil consumption.
But a recent experiment with a high-mileage Chevrolet engine was especially gratifying. A colleague owns a 2007 Silverado equipped with a 5.3-liter engine. As this vehicle approached 100,000 miles of service, the engine was consuming more than one quart every 750 miles.
First, we tried BG's No. 109 chemical during a routine oil change. We used the same conventional, 5W-30 oil my pal had used for years. Oil consumption didn't change. But then we repeated the No. 109 “therapy” during the truck's next oil change. Plus, we upgraded to 10W-30 Mobil 1 synthetic oil (a small bump in viscosity).
Call it snake oil, call it a sleight of hand—but I'm a believer once more. The truck's oil consumption is now a measly one quart every 3,500 miles. Plus, the slightly heavier oil has had no impact on gas mileage or cold-weather cranking—after all, it's synthetic.
Now, I'm not pushing these products and I'm not saying that this is the only way to cure oil consumption complaints. But I am stating that prudent experimentation on your part may help your business exceed customers' expectations again and again.