hey guys l just want to ask if its ok to use mobil 1 fully synthetic in the winter on a 1997 volvo 850 R with 103000 miles on it?

 

A synthetic oil would be the preferred choice any time of year and is the recommended oil in your owners manual. The manual recommends different weight oils depending on the temperatures in different areas. Look in the owners manual on page 9:2 to see what weight Mobil 1 you should be running for your area.

 

Been running Mobil1 since the day it became mine.

 

Changed the oil in my T-5R about 2 weeks ago and the oil in my daughters S70 GLT yesterday. Both now have Mobile 1 full synthetic high mileage 10W-30.

 

thanks guys. should l go for high milage mobil 1 10w-30 or just full synthetic mobil 1 oil for that kind mileage? thanks

 

I would NOT consider that car to be high mileage. I have 198,000 and would have preferred standard synthetic. From the feedback that I have received, people don't think the high mileage stuff will hurt but I like the standard stuff. They think the high mileage stuff will help keep seals healthy due to their age. I got it because the cheapest place to get oil in my area doesn't carry the oil I want in the weight I need so I felt forced to get the high mileage stuff.

Castrol is my favorite, Mobil 1 is my second choice.

 

OK, so not quite apples:apples, but I put full synthetic into a high mileage BMW airhead MC and REALLY regretted it. Stuff leaked out of every orifice like a sieve. Went back to 10-40 and things went much better.

I don't buy the anecdotal testimony about synthetic oil being better for seals. The stuff is too slippery and old, worn seals need thicker, "stickier" material to keep them flexible.

Also have had to deal with a VERY worn bunch of valve seals. I wouldn't dare run syn or anything less than 10w on it now due to very high oil consumption. Waiting for funds to get a rebuilt cylinder head this spring.

Not a chemist or engineer, but experience says "yellow light".

 

Synthetic oils do not cause engines to leak oil. In fact, All synthetic motor oil is fully compatible with modern seal materials and is properly formulated to condition seals, keeping them pliable to prevent leakage in an engine that is in "sound mechanical condition". If the engine leaked before the change over it will leak worse with synthetic oils. Two reasons for this: the synthetic molucules are all uniform in size which reduces friction and allows the oil to flow better, in some cases flow better out of a bad seal. The second reason is due to the additive package. The better the additives the more the oil can reduce sludge and keep the oil and engine components clean. Sometimes oil can remove sludge that is actually sealing a faulty seal that is failing or about to fail. Having owned 5 BMW motorcycles i have to say i have never experienced the problem that tmaximusv had but if the seal were not sound it would leak with either oil eventually. Just to let you know i do sell and use Amsoil Synthetic oil and have done so for the last 25 years so take it for what it is. However i have also owned a MC race team and raced a Porsche 944 for the last 10 years and used Amsoil products. Mobil 1 is also a very good oil and should not cause any issues if the seals are in good shape. 103000 is not high mileage.

 

If it leaked out of engines it wouldn't be as popular as it is and Valvoline, Castrol, Quaker State ... etc wouldn't have jumped in and tried to get their market share.

Volvo recommends synthetic. It may leak out of an air cooled BMW but we aren't talking about air cooled Volvos.

It doesn't leak out of my Volvo turboed 2.3L, two ford 4.6's, a supercharged ford 3.8 or my Chev 454. I think you're safe to run it.

In the minds at Mobil and Castrol 75,000 is where they start to recommend their high mileage oils.

 

The leak or consumption/burning[leak past the rings], is a bigger function of viscosity, and less of a seal's grippness/slackness .
So the choice should be carefully made between mobil 1 grades 10w 50, and 5w 40, and 0w-40.
If the regular recommended oil on BMWs and Audis, for old models, is 20w 50, then a 10w 50 Mobil synthetic will ve tendency to seep...and 5w 40 may leak.

I remember a Honda lawnmower recommending 10w30, and i very hot weather I chose wrongly to use 20w50...couldnot pull the engine cord to start..
The Japs typically had tighter tolerances back even in 70's when Europeans were liberal in tolerances for machining[less rejection rate]t, and hence needed thicker oil.

But since thicker oil being more viscous, takes away efficiency, every one now wants to get more mpg, hence thinner oils and precision in machining which now a days is easy.

However, it seems to me that high mileage oils[regular], are part synthetic...but a high mileage full synthetic must ve additives that I don't know as to what these do...help recondition seals. ?.. or deposit some on the worn out metal surfaces...like RESTORE claims...?

 

High mileage oil has stronger cleaners to break down sludge and capture contaminants and additives to help condition the seals so they seal better. That part I understand. What I've never been able to figure out is what makes "Truck and SUV" oil different. I called Valvoline and asked them. I was given an answer but it didn't make much sense and I'm guessing, guessing it isn't much different than "regular". They most likely have a different additive package but other than moisture if it's off roaded I can't see what a truck or SUV encounters that most cars don't. Most 4X4's and SUV's never leave the road, at least not on purpose and usually you only see one person in them.

I'm an older dog and always like(d) to run thicker oil due to a heavier right foot. What I did find out was in both my ford 4.6's ford recommends 5W20 all year long. I always thought is was a bit thin but I was warned that the reason for the thinner oil was two fold. One is mileage and horsepower. The thinner the oil the easier the engine turns and if you're looking for maximum mileage and horsepower the thinner you dare go, the better the return of both. I have no clue how small a gain it is but it's there and that is one reason you see zero W whatever oil in more and more new cars. I'm waiting for the first company to come out with a minus W something.

Secondly, things like camshaft clearances have been getting tighter and if you use a heavier than recommended oil like I was into these engines you run the risk of not getting enough lubrication to the cam bearings during a cold start. Sooo instead of going to something thicker than recommended it's better to just change it sooner if you're hard on it. That and adding an oil cooler can prolong the oils life also. Temperature is the big killer of P.S., transmission and engine oil.
I use Ford for an example as I ran into a Ford engineer and asked him why.

 

+1 same with mine

 

Wow! Oil stories! Yay! Um I don't know I use 10w-30 normal oil non synthetic!
Well since we're going all "technical" the chemical reason behind the synthetic oil will cause leaks is....... Synthetic oil is man made and the the "polymers" do not swell when heated up where in conventional oil the polymers do swell. So that's my quick chemistry lesson! Actually a company I worked for actually tested out oil filters, whether it was dealer/ "factory", or store brand the bypass valve on the oil filters opened up and bypassed the element after about 1200 miles. So in theory if you change your oil filter every 1000 miles you should have clean oil and wont have to change the oil soo often! But hey that's up to you! A case of oil is cheaper than a case of oil! Just have to too off the oil everytime about a 1/2 quart! Not bad!

 

Edit^^^^ the end of that is supposed to say.......
"a case of oil filters is cheaper than a case of oil!"

 

@ Clean850R, you should be able to edit your post.

Besides that, when we got our S70 GLT, the PCV system was clogged. At the time I knew nothing aobut the system. Two months later I picked up my Yellow sedan and learned about the PCV system (the car inspector told me it was clogged because of the smoke out of the dipstick). I ordered a kit, and the weekend that I was going to replace it, we learned that our S70 was blowing out the oil dip stick. So I used the kit on it, iPD said the kits were the same. Two weeks later I replaced the kit on the yellow sedan. Well, about 14 months later I decided to change the oil in the S70 to full synthetic. When the next change was almost due, my daughter told me the car was leaking oil. I then seen the leak and a week later I blew out 2 cam seals. I believe it was due to the weak seals from the plugged PCV but the synthetic oil broke the camels back. When I pulled the cam seals I discovered that the seals were NOT oem. My guess is the car blew the cam seals out and the mechanic just replaced the seals without dealing with the cause. So, I'm from the belief that if your car is on the edge of leaking, synthetic will do the trick for you.

I don't really think that synthetic is better for rubber seals, I think the claim is that the "high mileage" additives are suppose to be good for seals, reguardless if the oil is synthetic or not. Now why Castrol, Mobile or any other company would call a car with 75,000 high is beyond me. To a Volvo, that's just broken in, if the motor has been serviced correctly. Most car motors are built to last 200,000 miles. Now to a '96 Saturn that has a motor life span of 120,000, yea 75,000 might be considered high mileage. My thought is that a motor worn past 1/2 it's life may be considered high mileage. Maybe even 74% of it's life. A well maintained 850 that can run 500,000 miles would not be considered high mileage until it has about 300,000. That's just my opinion. I guess a compression test would be the best gauge for that but who will do a compression test on their way to purchase oil???

I like the thought of synthetic oil because of what I was told about it being a better type of oil, which is suppose to just about elimanate engine wear. Most claims state that you can leave it in the car for more months and mileage. So using it and keeping the change schedule should make my motor last forever, or at least longer than I will ever own it.