People in Chicago have been hearing a lot about higher oil change intervals these days. Maybe you're wondering: What are the key issues?

Some new vehicle manufacturers are now recommending much higher oil change intervals than they have in the past. As much as 5,000 to 8,000 miles (8,000 km to 13,000 km) or more. This practice came under scrutiny when four of the largest new vehicle manufacturers announced that owners like those in Chicago were experiencing engine damage resulting from these higher oil change intervals.

The manufacturers' standard oil drain service for particular vehicles was scheduled at around 7,500 miles/12,000 km. People following these recommendations were experiencing engine damage. It turns out that oil sludge was building up. This caused small oil passages to clog and engine parts to fail.

What causes oil sludge? It's a factor of time and mileage. There are hot spots in every engine that cause oil burn off that leads to sludge. Also, water from normal condensation can build up in the oil. This water also creates sludge. Severe driving conditions lead to more rapid sludge formation.

Severe driving around Chicago includes short trips under four miles (six and a half km)  or trips under 10 miles/16 km in freezing conditions. The engine just doesn't get warm enough for the water in the oil to evaporate.

Severe conditions are at the heart of the problem. Stop-and-go driving, towing, dusty conditions, heavy loads, very hot or very cold temperatures, a car top carrier – these are all conditions that would suggest that the severe service schedule should be considered.

The severe service schedule has much shorter oil change intervals. People in Chicago just need to honestly evaluate how they drive to determine if they should change their oil closer to the severe service schedule or to the standard schedule.

Some types of vehicle will give oil change reminders. But it's important to know how that reminder is determined. For some, the reminder simply comes when the standard mileage interval has rolled around. Others use a computer algorithm that takes into consideration the number of cold starts, trip length, engine temperature and so on. It's programmed to approximate where on the standard/severe service spectrum you fall. Some more expensive vehicles actually have sensors that test the cleanliness and effectiveness of the oil.

For the rest of us, better safe than sorry should be the guiding principle. Talk with your Chicago service advisor at Tuffy Chicago (Diversey Pkwy) and work it out together. Find out what kind of oil the factory sends out in your vehicle. Sometimes it's a premium grade that costs more than standard oil – but it may be what's needed to meet a higher factory recommended interval.

If you're realistically conservative, standard grades of oil will take care of you year after year. If you want to push the limits, ask for a premium grade oil to give you extra protection.

So, what happened with those manufacturers with the problems from higher oil change intervals? They ended up extending the engine warranty for parts that were affected by oil sludge. But they had a stipulation – they lowered the oil change interval and the vehicle owner had to provide proof of oil changes at the new lower interval to keep the extended warranty.

 Tuffy Chicago (Diversey Pkwy)
1400 West Diversey Pkwy
Chicago, Illinois 60614
773-929-3622