1996 NA 850 Manual says 10W-30 Why Not 5W-40?

[PeteB]

From BITOG - seems the conclusion is to run 10W-30 due to oil consumption and that the engine is designed for it,
VovlvoHead makes some very interesting comments, but first seems to say go with the 10W-30 then at the end
suggests 0W-40, anyway it is good. Fascinating subject, I read about oils every 5 or 10 years and learn something
everytime:


Originally Posted By: sleddriver

In summary, it looks like the sled likes a bit thicker oil in this stage of her life. Less blow-by, the oil stays cleaner, mpg delta not noticeable, compression may increase with a thicker oil though. So I don't need a 50, nor even a 40, but I do need a thick 30. What say you all?


Sleddriver,

I think your experience is a good case study why the current fashion to thinner oils requires prudence with some older engine designs, and some European families in particular. Thin is not "in" for certain engine designs, this being one of them. The bearing, valvetrain, and ringpack architecture contemplated by the engine designers (and often quite a few other parameters including gallery mapping and pump clearances) sometimes dictate other choices.

The Volvo modular family (white block) is a case in point. Even though it is still in production, this is a design first conceived in the 1980's. Even in NA form, the engine outputs approximately 70hp/L, which is quite respectable. In the turbos, such as yours, outputs can reach 120hp/L. The original main bearing journals and ring pack were engineered around a heavier 30 or 40 weight oil. While more recent Honda and other engines are now built for very light weights, this Volvo engine family simply is not. Extreme efficiency was not a prime design goal - durability and mechanical robustness were. If you review its original specifications from the early '90s, the recommendations trend towards a 40 in moderately hotter climates, with never less than a 30 in any climate.

By the late '90s (1999 to be exact), to better comply with CAFE, Volvo undertook a major revision of the ringpack to better accommodate the use of lighter 5w-30 oils. To my knowledge, there have only been very minor revisions to the bearing architecture in this engine, but they can safely and efficiently tolerate a 30 weight oil both at main bearing journals and in valve train under most street conditions.

Your experience with significant consumption with a lighter weight is common, and shared by legions of other white block owners prior to '99. There is nothing new about these findings. Nor is it confined to "high-mileage" situations with them.

Your conclusion that the engine performs optimally on a heavier 30 is spot on. Many pre-'99 turbo owners use either that, or tip into a 40. More than than a heavy 30 is usually not necessary except at the extreme end of the turbo engine range (Rs and modified track engines), and issues of turbo spool up become more pronounced with such oils, affecting overall performance. There is a good reason enthusiast Volvo owners who track like oils such as GC and M1 0w-40.

For the post-'99 engines, good results on a slightly lighter 30 weight are typical, and 5w-30 is the most popular choice for most of them -- as Volvo intended.

The white block is more tolerant of ambients than most, and even in a place like Texas, you should be able to stay in the above ranges.

One lubrication fault that Volvo was guilty of here in N. America was laxity in specifying proper test sequence approvals, particularly as to the turbos. As a result, the field practice tended towards the long-OCI use of "starburst" conventional oils in turbos, which has proven a mistake. There are plenty of dirty and sludged dealer-serviced white blocks to show for it. For a turbo, an A3 synthetic is best for OCIs exceeding 5k miles.

As to particular oils in this engine, I have seen and had good results with the above two, with T6, and with M1 5 and 10w-30. The best consumption results have been with T6 and GC. PP has spiked consumption in every white block we've put it in, but the one UOA I was shown was very good nevertheless.

GC is an older formula now and can be hard to find. So in 2012, if I were to pick one oil for your T5 that you should be happy with, it would be M1 0w-40. Go to a NAPA with an AAA discount and I think it is around $5.50/qt.

ps: 182k is not much for that engine.

[sleddriver]

M1 0W-40 is indeed popular for euro-cars. If I recall, the formulation was being changed at the time I was doing research. I was looking for an A3 oil with a HTHS of 3.5cS. The HM version has this + seal conditioners + detergents. I've never had a UOA done.

GC was on it's way out or gone. PP was unavailable or too pricey. I'd been using Rotella T6 which was fine as a HDEO runs fine in these engines. Plus 5qrts of 100% premium (shell refinery) syn was < $20. Can't beat that!

The sled currently has > 215,000mi and is running great. I need a good road-trip as it's been awhile.

Finally, what works for me, here in Central Tx., probably isn't at all appropriate for those in the PNW or Minn. or the NE. Very different climates. During the Summer, it will still be above 90F > 10pm. When we had the big heat-wave a few years back, it wouldn't drop below 90F until 1am or so. This due primarily to the humidity, which can be brutal due to the Gulf and prevailing on-shore winds.

Here, we only have two seasons: SUMMER and February.

[PeteB]

That all makes sense, thanks.

Here's a link to Haas' papers for anyone who's interested:
http://www.supramania.com/aehaas/index-2.html

[cn90]

I am running Mobil 1 synthetic 15W50 oil.
Car has 180K miles, and oil consumption is as follows:

- 5W30 synthetic: 1 qt/700 miles or so.
- 15W50 synthetic: 1 qt/1500 miles or so.

[PeteB]

Thanks good to know, ours has high consumption also.
I bought 10W-30 yesterday, and we might run 15W-50 next summer since
there is cheap T6 in that weight.

[misha]

10w-30 will not lower oil consumption because it have the same characteristics at operating temperature(xx-30).The second index is important here.You would need xx-40 or xx-50 oil if you want to achieve that.

1st index(10w) shows characteristics for cold weather/cold starts and the 2nd(xx-30 or xx-40) characteristics at operating temperature.

[PeteB]

I am aware that that is the theory, but in practice people report a difference - anyway
to explain this?

I might try 5W-30 or 40 once we get the PCV fixed but for now I'm going as I stated above.

[misha]

I'm talking from experience and that is also the fact.
Cn90 also pointed that out.

Thinner oil-higher oil consumption.
Thicker oil-lower oil consumption.
Depending on how big oil consumption is with thinner oil....slightly thicker oil can make oil consumption to stop completely.

[bmdubya1198]

From what I've heard, unless you're in a cold climate, your really shouldn't use 5w30 in these cars. 5w40, 10w30, and 10w40 seem to be the most popular. I stick to 10w30. I recently changed my oil with Penzoil Platinum High Mileage Synthetic 10w30, and I think it's much better than the Valvoline I had in there. I've only got a couple hundred miles on this oil, but it's been good. Not as much lifter noise as the Valvoline. I got it on sale at Walmart plus a rebate, so it's a pretty good deal at $18 for 6 quarts!

I would avoid Supertech. The only generic brand oil I would use is NAPA, because it's made by Valvoline (which isn't my favorite, but it's pretty good). My cousin ran Supertech in his Durango (which as anyone who has had a Chrysler V8 knows drinks oil like it drinks gas) and the consumption was insane. Much worse than anything else, which goes pretty quickly as it is. This oil didn't seem to hold up well at all.

[misha]

From what I've heard, unless you're in a cold climate, your really shouldn't use 5w30 in these cars. 5w40, 10w30, and 10w40 seem to be the most popular

.

You're right and the truth is that anything xx-30 is too thin for these engines except for those who live in extreme cold climate areas,excluding 10w-30 viscosity.Excluding...because of 10w index.
0w-40,5w-40,5w-50,10w-40 are the most propriate for all year round use,for most climate areas...even in extreme cold ones,excluding 10w-40 which is for moderate climate area because of 10w index.

15w-40,15w-50 & 10w-60 could be used in moderate climate areas all year round.For summer temperatures and for hot climate areas...they are perfect.