Mazda RX-8's sporty appeal makes it a good used purchase

by Jim KerrBackyard Mechanic . Jul 13 2018
The RX-8 is a fun sports car with room for four adults. (Mazda)

The RX-8 is a fun sports car with room for four adults. (Mazda)

Question: I am pondering a purchase of a used 2010 Mazda RX-8 with a rotary engine. Any opinions you might share about the rotary engine?

Answer: Mazda is the only auto manufacturer that has offered a rotary engine in a mass-produced vehicle and even then, it only came in one model of their vehicle line-up. In the early days of the rotary engine, such as offered in the RX-3 and RX-4 models, the apex seals on the triangular-shaped rotary piston (the same concept as piston rings on a conventional piston) didn’t last long and the engine started to use oil. This was quickly corrected by Mazda and the rotary engine has proven very durable.

Before fuel-injected models appeared, most of the rotary-engine problems were caused by the complicated emission systems, as a rotary engine creates more emissions and therefore needs more extensive emission systems. Fuel-injected models are much better, and would appear to be as reliable as any of the other more conventional Mazda products.

The only negatives about the rotary engine that I have found are it does seem to be thirsty for fuel and there are no shops that do any engine work. If you need any major engine work, which is rare, the engine is swapped for a factory rebuilt unit.

The RX-8 is a fun sports car with room for four adults. Let others drive Ferrari or Lamborghini. The RX-8 is an appealing car on the road at a fraction of an exotic car’s cost. If the car is in good shape, go for it.


Question: I have a 2017 Chevrolet Equinox (with 17,000 km). I have had the oil and filter changed every three months as advised by the dealer. According to the General Motors manual, this vehicle is equipped with a computer that advises you when the oil should be changed. Should I continue to change the oil every three months or depend on the vehicle’s computer? I have sent two e-mails to GM, but so far have not received a reply. I would appreciate your advice.


Answer: Oil change intervals have traditionally been based either on time or mileage, and many repair shops recommend frequent oil changes. GM’s use of oil-life monitoring systems for the past several years on almost all their vehicles has changed that for most GM owners.

The GM oil-life monitoring system uses engine revolutions, engine load and engine temperature to calculate the condition of the engine oil. High r.p.m., heavy load and hot or cold engine temperatures will wear out oil faster than slow speeds, light loads and moderate temperatures. Under ideal operating conditions, the engine oil may not need to be changed for as many as 15,000 km on some models. Most drivers will see a “change oil” light illuminate before this mileage.

GM states the oil must be changed at least once a year even if the “change oil” light has not come on. If the oil-life monitoring system is accidentally reset, an oil change should be done within 5,000 km of the previous oil change.

Changing the oil at the intervals based on the oil-life monitor will save you money and help protect the environment by reducing oil use, and should protect your engine. But changing oil sooner will help reduce wear on items like timing chains or hydraulic lifters.

I would change oil sooner than the oil-life monitor indicates if the vehicle were operated in dusty conditions, where dust trapped in the engine oil could increase engine wear, if you do a lot of stop-and-go driving in cold weather or if I was going to park the vehicle for a few months.

If the vehicle was going to be stored, I would change the oil and operate it for a few minutes before parking the vehicle to prevent any acids formed in the engine from damaging internal parts.