Looks like marketing $ indeed well spent by oil companies. "Changing oil more frequently is good for the engine!"
Is it? Why not use a search engine called Google, or another tool called "search" at Club Lexus to research independently before believing to a source whom benefits financially from influenced user behavior?

 

No doubt that changing your oil more frequently is better for the engine. But that "better" is so small that it isn't noticable. Change your oil every weekend and it will be better for your engine. But the unmeasurable engine improvement will never match the economic and environmental costs.

I have always changed my own oil at 5,000 mile intervals and I've always used dino oil. I've never had a major engine repair. My cars when I sold them:

1972 Toyota Celica - 265,000 miles
1985 Toyota Camry - 257,000 miles
1982 Toyota PickUp - 204,000 miles
1998 Dodge Caravan - 206,000 miles

I'm currently using Mobil 1 in my ES350 every 5K and I don't know why because I know it's not needed but as gsrthomas said, "It makes me happy."

 

Local Toyota/Lexus specialty shop regularly sees engines w/ 300k+ miles with 4k intervals w/ standard oil.

But it makes sense that high temps, heavy towing, dusty environment, etc would require sythetic and/or 3k intervals. Other recommendations for Toyota/Lexus (normal use):

1. Change oil & Filter every 4,000 Miles to prevent Engine Sludge & lower maintenance cost.
2. Check all Fluid Levels & Condition of Fluids every 4,000 Miles.
3. Inspect Tires for condition wear & correct Air Pressure & Rotate every 8,000 Miles for maximum tire life and prevent tire failure.
4. Inspect Brakes every 8,000 Miles (We inspect brakes free on every 4,000 Mile service.)
5. Transmission Fluid changes every 30,000 Miles to remove Contaminants to extend life & Prevent failure.
6. Power Steering Fluid Flush every 30,000 Miles (Power Steering System is the hardest working part of your vehicle. Fluids need to be changed to prevent leaks and failure of Pumps and Racks.)
7. Differential Fluid & Transfer Case (Trucks & Rear Wheel Drive Cars.) Change every 30,000 Mile & Manual Trans Drain & Fill.
8. Fuel System: Replace Fuel Filters every 30,000 Miles, Power Flush Injectors & wash intake Plenum every 30,000 Miles and Injector Cleaner to tank every 15,000 Miles.
9. Cooling System Inspect belts, hoses flush coolant every 30,000 Miles or 2 years.
10. Timing Belt Replacement vehicles with 5SFE 4 cylinders engines Camry's, Celica's and Rav 4's Replace at 60,000 Miles. All others 90,000 Miles.
11. Tune ups Spark Plugs non Platinum 30K, Spark Plugs Platinum 60K.
12. P.C.V. Positive crank case ventilation valves every 15,000 Miles.

 

BUT, if you do a lot of freeway driving on a consistent basis, you can avoid those lower oil change intervals. The sludges don't have a chance to build up under the high temps of freeway driving. Plus, the constant speed significantly reduces dirt buildup.

 

I do mostly city driving....about 40 mi. per day just to get to work...not to mention drives to go to other places...My oil change time is about 3500-4K mi. max.