Synthetic Blend Oil

I’ve got an 8 cylinder 2005 Ford Econoline with 130,000 miles. Is it worth switching from conventional oil to synthetic or synthetic blend. I go 5000 miles between changes with conventional. The speedy oil change guys, of course, say 3000 is best. I know better because I listen to Car Talk. Still, I have heard that I can go 10k with synthetic, but then I hear that the filter is only good for 5000 miles. What to do? Lou Houck, San Antonio, TX

If you are having no probles, just keep doing what you are doing? Unless you are living in an extreme temperature area or the engine runs hot I don’t think you would be changing anything except what you pay.

The problem with synthetic blends is that there is no easy way to determine what the mix is. It could be 5% synthetic and still be marketed as a blend.

Considering how many miles are on the van in a relatively short time, I imagine most of your driving is done on the highway. Check your owner’s manual to see if your driving qualifies as “normal service”. You could then safely extend your oil change interval to the maximum recommended by Ford, using full synthetic to add a little safety factor.

Agree that unless you live in extreme heat or cold, synthetic oil is not cost-effective. An oil will only lubricate properly as long as its additive package lasts, which is not much different in synthetic oils.

Unless you do a lot of stop and go driving and drive short distances, 5000 miles is OK with today’s oils. If you do drive short distances, 3000 miles on normal oil is your most economic choice.

Also note that Ford has resisted changing intervals on their trucks to beyond 5K miles, regardless of conventional, blend or synthetic used. I would stick to a 5K interval and use either conventional or whatever is on sale at a good price. I am using Motorcraft with good success in my Ford trucks, and a 5K interval.


OIL: Synthetic can always replace standard. Unless the owner’s manual (not the dealer and certainly not the quick oil change guys) says it needs synthetic, IT NEEDS SYNTHETIC. Using synthetic if it is not “needed” may save you a little on fuel, will not hurt the car in any way and could (but may not) extend the life of the engine. Do not extend your oil change interval beyond what the owner’s manual recommends for your type driving!

The speedy oil change guys: Keep away from the quick change places. We hear far too many horror stories about them. Some may be fine, but many pay the help little, demand fast changes and that results in a high percentage of errors. Too many live by selling you something you don’t need at inflated prices.

Find a good local mechanic and stick with them for your needs.

Don't go to the quick lube places, even for directions.