How far is too far?

Bob, do you hang out on BITOG? Those guys would find this interesting.

Or maybe you ARE The Oil Guy.....

I am an oil guy.... buy I'm not that guy. And no, I don't frequent that locale.

I've been running 7500 mile intervals in my Mazda since it was new. It uses 0w20 Synthetic, which is basically water. When I first bought it, the only available oil was Mobil 1. Now, a few other brands make 0w20 that's readily available, like Castrol. The car doesn't burn a drop, and the oil doesn't even look that bad when I drain it. I should do an oil test at some point.

I started long mile oil changes in '94. With full synthetic oil. Once a year, usually about 9K miles. Been doing that ever since. Just did the 4th oil change on the Fiesta, 35900 miles.

We sold oil change additives with an oil change from the 50's into the early 2000's. Did they work? I think so, but can't prove it. Did they hurt? Not that I ever saw. Were they profitable? Damn straight, and for years everyone in the building had jackets, hats, t-shirts, pens, pads, coffee mugs, you name it. I still use a product in my 90 Miata, but it's kind of from force of habit. Your actual mileage may vary.

I just brought home a 1984 Toyota 4-runner (22r) that still had it's owners manual. Recommended oil change interval was something like 8000 miles iirc (with 1984 oil!!)

The only problem I've had with oil is since my wife started doing a short commute of about 3 miles to work. I have to change the oil once a year otherwise bad things can happen. I found this out after I popped the cap off after 3000 miles (probably a year and a half in) and there was noticeable sludging under the cap. This is with 5w30 full synthetic.

That short commute, especially in the winter months, is a killer. I also take the car for longer drives once a week now to make sure it gets heated up.

I do that too.

Harvey wrote: The only problem I've had with oil is since my wife started doing a short commute of about 3 miles to work. I have to change the oil once a year otherwise bad things can happen. I found this out after I popped the cap off after 3000 miles (probably a year and a half in) and there was noticeable sludging under the cap. This is with 5w30 full synthetic. That short commute, especially in the winter months, is a killer. I also take the car for longer drives once a week now to make sure it gets heated up.

Invest in a Frostheater or at minimum an oil pan heater. I too have a short commute in a very cold winter and will do longer trips to make sure the oil gets hot enough to burn out contaminates on the weekend.

Hungary Bill wrote: I just brought home a 1984 Toyota 4-runner (22r) that still had it's owners manual. Recommended oil change interval was something like 8000 miles iirc (with 1984 oil!!)

Aren't those the engines where the timing chain gets so loose that it beats a hole in the timing cover, allowing coolant to dump into the oil?

What is the most common cause of oil turning black? I'm doing 5k intervals in the SL2. It doesn't burn much, which is basically unheard of, but it will make the oil black with a quickness. And that's using the filter twice the size as stock. Average trip is 10 miles, 15-20 minutes.

We also do 5k intervals on the wife's Ecotec Saturn, which is proably overkill. Average trip is ~7 miles, 10-15 minutes.

Knurled wrote:

Hungary Bill wrote: I just brought home a 1984 Toyota 4-runner (22r) that still had it's owners manual. Recommended oil change interval was something like 8000 miles iirc (with 1984 oil!!)

Aren't those the engines where the timing chain gets so loose that it beats a hole in the timing cover, allowing coolant to dump into the oil?

Short answer: yeah

Long answer: no. The timing chain isn't really oil related. Sometime around '83/'84 Toyota decided to reinvent the wheel and remove the dual row (bullet proof) timing chain with metal tensioner from it's 22r production line and they replaced it with a single row chain with a plastic tensioner. The plastic tensioner breaks most commonly at it's top mounting point (heat cycling is blamed) allowing enough slack for the chain to hit the housing and wear through the timing cover's water jacket, BUT there is an aftermarket metal backed plastic tensioner solution that gets us 22r nuts around all that.

ProDarwin wrote: What is the most common cause of oil turning black?

Does it burn oil? The extra soot from oil consumption can darken up oil quite a bit. Fuel dilution from short trips tends to make oil black as well.

Dark oil isn't usually an issue though. As long as there's a filter in the system, appearance usually isn't too strongly related to the oil's condition.

Just shows that the detergents are working.

All of this brings up a question I have been pondering: is it appropriate, before a HPDE/track day, to do an oil change with true racing oil, then do another change back to street oil immediately afterwards? It seems I have read that racing oils (intended for a very short OCI) somehow do better at protecting an engine being operated at high RPM and high load. Thoughts?

In reply to WildScotsRacing:

It depends on the engine. Some engines are rougher on oil than others. If it's an engine that doesn't have any overly particular oil needs in general (like a flat tappet pushrod motor would), doesn't run super hot oil temps and doesn't have any ridiculous valvetrain or anything to handle really high revs with aggressive cams, I'd probably skip the racing oil (as it'll give very little benefit).

In reply to WildScotsRacing:

Unless you're seeing really high oil temps and won't put a cooler on it, I doubt there is any benefit.