Synthetic oil


#1

I drive a 98 Volvo S70 which has about 126,000 miles on it. My parents are the original owners of the car, then they sold it to me. Except for one time, the car has always had synthetic oil in it. I seem to get various opinions as to how often I should change the oil. I believe the oil should be changed every 7500 miles, but every mechanic save for one has said every 3000 miles. I think they tell me 3,000 so they’ll get more of my money.



I’m curious to know what others out there in cartalk land think.


#2

change oil and filter every 3000k to be safe. its not that expensive and they might spot other minor things that can be remedied before they become expensive.


#3

I believe the oil should be changed every 7500 miles, but every mechanic save for one has said every 3000 miles. I think they tell me 3,000 so they’ll get more of my money.

That’s EXACTLY what they’re doing. They’ll get twice the money out of you if you change the oil every 3k as opposed to 7.5k. 3k with synthetic oil is NOT necessary.


#4

[/quote]change oil and filter every 3000k to be safe. its not that expensive and they might spot other minor things that can be remedied before they become expensive.[quote]

when you use synthetic oil it would be expensive to change every 3000. i thought using synthetic allowed you to go 7500 miles instead of 3000.


#5

Look in the owners manual. I don’t know about your Volvo but often there are 2 oil change interval schedules. One for normal driving conditions and one for harsh conditions. The intervals are often 7500 miles for normal condions and 3000 miles for harsh.

Harsh or sever conditions are usually defined as allot of city driving, pulling a trailer, in very hot or cold climates or driving on dirt roads.

If you are not 100% sure of where you fit in to this, play it safe and change it around the middle of the two.

The Synthetic oil should last longer and provide more protection than the conventional oil. So this is a consideration as well.

The engine may burn oil more with the synthentic and you may have to add oil more often in between oil changes. You will learn this by experience.

In deciding your oil change intervals and which oil to use you need to consider the $ cost to operate difference along with the type of driving you do.

You may want to question your mechanic on why he suggests 3k oil changes if your manual says otherwise.


#6

Using a 3000 interval with synthetic is probably overkill, it won’t do any harm but it’s a little more expensive. If you don’t mind the cost, just do 3000 miles and don’t worry about it. If you want to extend the interval, check your owners manual and use that as a starting point. Personally, I do 5000 mile intervals with synthetic, but that’s probably conservative. If you really want to know, have a used oil analysis performed and determine the exact condition of the oil.


#7

First the only real authority is the owner’s manual. Follow what it says and as noted, consider how you drive it and see if you fit into the severe conditions.

Today’s cars and oils are far different when 3,000 miles was the rule. Many mechanics and oil change places like to dig up that old figure to help make their boat payments. Don’t believe it.