Ask TundraHQ: My 2007 Tundra Is Burning Oil – Is That Normal?

A reader writes:

I have a 2007 Tundra with the 5.7 that I purchased brand new in the spring of ’07. The truck has ~64k miles, has been serviced at the dealership since it was new, and has not been abused. I’ve been using Mobil 1, changing the oil every 10k miles. I noticed when checking the oil before my 60k service that it was down about 3/4 of a quart on the dip stick. The dealership’s service department said they have never heard of a Tundra using oil, especially at only 60k miles. Is this normal, or is something wrong?

Short answer: There could be something wrong, but more likely than not everything is fine. Here’s some more detail.

New Engines Don’t Burn Much Oil, But They Burn Some

As a general rule, newer engines (1990 or later) don’t burn much oil unless:

1. They have active fuel management (aka cylinder deactivation), which can lead to substantial oil consumption and/or
2. They’ve got lots of miles…at least 100,000, and typically 200k+. Rings and seals don’t last forever.

Therefore, a 60k mile 2007 Tundra really shouldn’t be burning oil (at least not much – more on that below). We’re not specifically aware of any problems with 2nd-gen Tundras burning oil, nor any other recent Toyota models. This isn’t a “Tundra problem” we’re aware of.

Still, most owner’s manuals suggest that vehicles can and do burn oil, as they recommend checking oil levels between changes. This is because engines can “consume” oil in a variety of ways:

• Some engine designs call for ill-fitting pistons (more on that below)
• Seepage thru various seals (albeit minor)
• Carbon deposits
• Oil that’s too thin (oil that wasn’t designed for your engine)
• Dirty air filter, clogged PCV system, and about a dozen other unlikely possibilities

Generally, most people accept that engines will consume less than a quart of oil between changes. Some vehicle manufacturers (Ford and GM) say that engines can consume as much as one quart of oil every 1,000 miles with no adverse effects. However, this much oil consumption is sky-high as far as Toyota engines are concerned.

What’s Going On With This Tundra?

Two items caught our eye.

First, the 5.7L Tundra has eutectic pistons, as they’re designed to accommodate the TRD supercharger. This means that they’re a little more expansive than pistons used on other Toyota engines.   To ensure these pistons don’t expand beyond the confines of the cylinder, they’re made to be slightly out of round when cold. Thus, the rings don’t form a perfect seal between the piston and the cylinder wall until the pistons themselves have warmed up. A little oil is going to sneak buy until the engine is warm.

If this Tundra doesn’t spend a lot of time at full operating temperature (because it’s used for short trips mostly), it’s going to consume oil more than expected.

Eutectic pistons expand more than hypereutectic pistons, but they’re not as brittle, and thus ideal for an engine that may be supercharged.

Second, the recommended oil for a 2007 5.7L is 5W-20. If you’re using 0W-20, you may find that the engine consumes a little oil, as it’s a bit too thin. Toyota didn’t recommend 0W-20 oil for the Tundra until 2010.

While using 0W-20 oil on a 2007-2009 Tundra won’t hurt anything, it might very well cause oil consumption.

How To Check Your Truck For Oil Consumption

Checking for oil consumption is easy – just be sure to compare a dipstick reading in the same circumstances. Don’t park your truck on an incline, check the oil when it’s hot, and then repeat the check when the engine is cold and the vehicle is parked flat. (Ideally, you could check oil levels when the truck is parked on flat ground and the engine is nice and hot.)

If you’ve checked the oil and notice oil consumption, try and get a grasp on how much. If it’s a quart or more between oil changes, it’s something you need to monitor. If it’s half that amount, don’t give it much thought.