Are Car Maintenance Interval Suggestions Completely Bogus?

My mom always told me to do 5000 miles so that's what I do without any problems. I always noticed the sticker say 3000 but I've never followed that advice. That would be way too much money and I don't think it would do anything positive for my vehicle.
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I tend to keep oil changes at every 3000 miles regardless. That seems to avoid a lot of problems. But I think we can get carried away with scheduled maintenance too. There's the part of me that thinks there's also the dealer revenue stream embedded in that schedule as well. For example, some books will recommend changing belts and hoses every so many miles, but if they aren't worn or cracked what's the point?

I'm with you on the "feel' of the car, that tells a lot. No matter what you do or don't do on the maintenance side, somethings will still wear out or break, more on some vehicles than with others.
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I was doing 3K when I put the regular stuff in. Now I am using Synthetic, but you're right…the car shop still puts the sticker for 3K, because that is what is under my 'cars guidelines'.
I guess if they put different than what is stated from your car guide instead of holding to what the oil guidelines, they could be held liable? But now that I am using synthetic, I change it every 5-6K. My husband's car only needs to be changed every 10K! Would love that, especially with all the driving I do. And yes, I do keep my car maintained like clockwork. Never had any major problems with it so far (knock on wood).
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Notes from a mechanic
Your questions about oil change frequency and Synthetic vs. Regular oils are very common, and hopefully I can explain them in simple terms, without resorting to techno-babble.
Oil in your engine does two things, reduces friction and seals the microscopic imperfections between the pistons and the cylinders. The lubrication is accomplished when the oil leaves a microscopic film between two moving, metal parts. Oil helps seal the combustion chamber by providing a thin, frictionless sealing material between piston rings and the cylinder walls.
Regular oil, being a refined "natural" product, is comprised of different, but related, molecules of different sizes. Synthetic oil is manufactured compound that is comprised of molecules that are all the same size. This allows synthetic oil to coat the parts more evenly. It also allows manufactures to design engines that have closer tolerances, because less oil is needed to maintain the level of lubrication. Older engines have more space between the metal parts to allow for enough regular oil to coat the parts where it is needed.

My newer Civic has a computer that tells me when to change my oil – after 2 years I am averaging about 5,100 mi per oil change. Sometimes more, but I just do it every 4 months (3X a year) and do it myself (avg about 4,400 mi per change). Other than cost, there is little downside to changing your oil more frequently. Clean oil lubricates better and keeps your engine cleaner.

I use synthetic and buy enough for a couple of changes whenever it is on sale. Combined with a premium filter I can change my oil for $20-$25. Local shops would be $50+++ for full synthetic change, so the savings are significant.

If I used conventional oil, I would change it every 3 months. I did that on my last car and at 200K miles it was still going strong!

And always recycle your oil properly if you DIY

I've always read that with newer cars you can extend those intervals. Actually my 98 Cavalier suggested every 5,000 miles and 100,000 between tune-ups!
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