1998 XC - Type of oil to use

aloggia · Post by **aloggia** » 23 Dec 2009, 10:02

Hi all. I have a question about the type of oil I can use in my car. I apologize if this topic gets beat to death but I did a quick search and didn't find the answer I was looking for.

I've got a 1998 XC with 128K. I've been taking it to a reputable service station near my house for several years. When they change the oil, they put in Synthetic 5W40. I've got no problem with that; everyting runs fine. Occasionally, I need to add a little bit of oil to the engine. The problem I have is that if I go to my local automotive store, I can't find Synth 5W40. I can find Synth 10W40 and Synth 10W30 but not 5W40. I'd like to put in the same type. So my question is, what oil can I safely use?

Thanks for the advice.

Post by **FlyingVolvo** » 23 Dec 2009, 10:15

5W-40 is not one of the recommended oils for that car (as far as I'm aware). Usually 5W-30 or 10W-30 are the ones used. It really depends on where you live and operate the car regularly.

If you live somewhere really cold, use 5W-30, if not 10W-30 works for nearly anything. Do you have an oil leak?

I really recommend Mobil 1 10W-30 High Mileage oil, it's good stuff! I've got a 2000 V70XC.

aloggia · Post by **aloggia** » 23 Dec 2009, 10:25

ecbsykes wrote:5W-40 is not one of the recommended oils for that car (as far as I'm aware). Usually 5W-30 or 10W-30 are the ones used. It really depends on where you live and operate the car regularly.

If you live somewhere really cold, use 5W-30, if not 10W-30 works for nearly anything. Do you have an oil leak?

I really recommend Mobil 1 10W-30 High Mileage oil, it's good stuff! I've got a 2000 V70XC.

I live in VA were the temps can be as low as 10/20s in the winter and as high as 100s in the summer.
I always thought 10W-30 was about right and put that in my other cars. I was a little suprised when they recommended 5W40 but I do trust these guys. As for an oil leak, they resealed the turbo oil return line which was leaking. I haven't noticed anything recently. They recommended something like 5K or 6 months until the next oil change with, from what I hear with syn oil, seems to be somewhat accurate. I don't drive the car enough to hit the 5K before the 6 months (short commute).

Post by **FlyingVolvo** » 23 Dec 2009, 11:22

A lot of times what people will do is use 5W-30 for those colder months for a little more engine protection at start-up, and then switch to a higher weight oil (10W-30 or so) during the hotter summer months when you don't want to risk cooking the oil and don't need that extra start-up protection.

While supposedly 5W-30 and 10W-30 are the exact same when the engine is at operating temperature, I have heard that there are negative attributes to oil who low and high viscosity rating are farther apart from each other like a 0W-40 or something. I thought I read something explaining that it doesn't hold up as well to extreme temperatures as well. Anyone care to enlighten?

Post by **misha** » 24 Dec 2009, 13:21

5w-40 will work just fine.

I'm not at home right know to post recommendations from Volvo about oil viscosity,but 5w-30 is for temperatures up to 20 degrees celsius(68F),according to that recommendation.

Which oil viscosity you will use really depends from the climate in area where you live.
For moderate climate,recommendations from Castrol,Shell,Liqui Molly are 10w-40 semi-synth.

So,5w-40 will give to your engine greater protection when engine is warm and in hot days, than 5w-30...and you'll have the same protection on cold starts like with 5w-30.