CarTalk.com Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

Oil change

My mechanic cousin says to change my oil every 3,000 miles no matter what. My 2008 Honda has a computer that tells me when to change my oil (usually 5,000-7,000 miles). Should I go by the computer or what my cousin says?

Go by when the car’s computer says to change the oil.

Is your cousin a mechanical engineer who works for Honda and was one of the designers of that Hinda engine???

I don’t know how your Honda computer works, but my Chevrolet Uplander has a message bar that tells me the % of oil life left and then gives a message to “Change Oil Soon”. This varies–in my stop and start winter driving the message may be flashed as soon as 3000 miles. In over the highway summer driving, the oil may go 7000 miles before it advises to “Change Oil Soon”. This has been the system I used for years before we had such devices. My shop always puts a sticker on the upper left corner of the windshield as to the date and mileage when the oil was changed. I monitor that as well. My experience is that the computer readout on the Uplander just reinforces what I have always done with my cars.

No, but he says he has done enough oil changes to see that almost always the oil is breaking down in all cars after 3,000 miles.

I can’t hurt to change your oil more often. A lot depends on your driving patterns too. The owner’s manual for my 99 Accord says to change it every 7500 miles, do you really think I wait that long in between changes? No, of course not. Oil changes are cheap so if in doubt, do it more often.

“to see that almost always the oil is breaking down in all cars after 3,000 miles.”

How could he possibly know this? The only way is by having an oil anlysis done. Oil gets dark over time, that by itself doesn’t mean it’s ‘breaking down’. If you really want to know, ignore your cousin and send in a sample for analysis.

I am not a fan of the engine computer for oil changes. I currently have a van with this system that for the 1st 100K miles of its life had its oil changed by the computer. The interval turned out to be every 6500-7000 or so. Its one of the dirtiest engines I have ever seen. (I ignore the computer and do it every 3-4K).

I’d ask this about the computer systems: does the “engineer” or the manufacturer really care how long my engine lasts? They care for maybe 75K to 100K. That’s pretty easy these days even with dirty oil, but I want a lot more than that. Their interests are more short term - this year’s sales - and part of the “competition” recently is about the appearance of low maintenance. So, e.g., witness “engineers” and manufacturers who say to never change transmission fluid or give something like 100K trans service intervals. In short, there are lots of things that I just don’t trust about this stuff and the “oil life” systems are one of them.

As for helping the OP sort it out, it won’t hurt the car to change the oil more often. Nor will it actually cost all that much more $$ over the life of the car. By the same respect, however, what is your long term interest in this car? Will you drive it for a few years and then trade it in? Or will you meticulously care for it with the intent of keeping it a really long time and driving it until its dead?

If you’re not with it for the long term, use the computer. When you go to sell it you will be able to honestly say that you followed manufacturer recommendations. If you’re in it for the long term, ignore the computer and change the oil every 3-5K (I’d put 5K at the absolute outside).

Changing the oil every 3000 miles certainly won’t hurt anything. But if you drive 3000 miles per month, you’ll be spending a lot of money.

I am in it for the long haul so I think I will change it every 3,000-5,000 miles. I have a 2002 Honda Civic that requires synthetic oil and I change that about every 3,000-5,000 miles. It’s the first time I have had a computer and that’s why I was questioning it, especially after my cousin said what he did.

Thanks all for your input!

I didn’t realize Civics require synthetic oil…is that in the manual?

For some reason it’s only the 2002 Civic, and yes it’s in the manual that I can only use synthetic oil.

This is an argument that has been going on for some time since auto manufacturers have been extending oil drain intervals over the past years. I like what Ray & Tommy have said here: http://www.cartalk.com/content/columns/Archive/2005/March/01.html