I just thought I'd throw this out there for information. I understand I'll hear from folks I'm wasting mileage with regard to each oil change. However, I have a truck I use to pull my car hauler. So it gets worked very hard. I know I've had it overloaded from time to time. It's a 98 Dodge Ram 360 engine. During a trip a couple weeks ago to the Cleveland area I managed to smoke the trans.
So this week I pulled the tranny and while I was under it, I pulled the oil pan to replace the rear main seal, and take a look around while I was in there. The truck has 220,000 miles on it. All of them working miles. I pulled number 5 main bearing to check the damage or wear. Seems the bearing had no signs of wear, so I got out the bearing Mic and check it. No wear around the entire half of the bearing I had out.
Here is where the oil issue begins. At 30,000 I changed to full synthetic oil. I still changed the oil on the same schedule I've always used since my first oil change back in high school. I change every 2,500 miles. I know I can go twice that or three times that number, but I don't. I run it up on the rack at or around 2,500 and change it. My cost is under $4.50 a quart so what the heck.
The old girl is closing in on a quarter of a million miles without bearing wear. She does need a timing chain and the front crank seal, but rods and mains are looking good. I guess that says something good about synthetic oil.

 

That's why the manufacturers of most high-end cars (and others) put full synthetic oil in their engines and recommend/require it during oil changes. It's that much better.

But, for a car that you only put on 2000 to 3000 miles per year, it's a toss-up as to what to do. Cost-wise, it's double the cost and we'll all be dead before a "good" engine is worn out. But, wear-wise it's a "no-brainer". So, each owner has to do what's "right" for THEM.

 

I have a good friend that has a 89 oldsmobile don't remember the model, but it's a family sedan. His father owned it first. From day one they used synthetic oil. Changed the filter at 5000 mile and the oil at 10,000 miles. 347,000 miles later it still runs and uses no oil. Don't know the condition of the bearings other than they make no noise. Synthetic oil gets the job done, no doubt.
I've use it for at least 10 years now and do the 10,000 mile oil change with 5,000 filter and no complaints yet. Last car had 230,000 miles on it when sold still running strong no oil usage. Good filter and good oil and things last a long time. Current car, 130,000 trouble free miles.

 

Get that timing chain changed ASAP. I drove a motorhome with a 360 pulling an enclosed race trailer all over the country when I was racing the Top Fuel bike. The motor was strong, used no oil and was even pretty good on gas. One day I was leaving a race in Clarksville Tennessee, I started the motor and it died. Cranked again and I could tell it had no compression in any cylinder. It took the teeth off the top sprocket on the cam and bent every single valve and pushrod. Had the same thing happen in a friends Dodge van on a trip. It also bent every single valve and pushrod. Yours will do the same thing if you loose the timing chain/gears!

 

That is exactly what I'm thinking. I guess you know how it goes when it comes to taking time to work on your own stuff. It always seems to get put on the back burner until the last second.