American vs. European / 30 vs. 40???

Justin · Apr 30, 2003

When changing the oil recently in two European cars (Volvo 2.4 NA, VW 1.8T), I've noticed that they both list the typical 30-weight oils (5w-30 for both/10w-30 for Volvo) as primary recommendation. BUT, they also both say that when running hard, towing, etc..., that the use of 40-weight oil (15w-40 and 5w-40 for Volvo...5w-40 for VW) is recommended.

Now looking at American cars and trucks, most require that you use 5w-30 and 10w-30, and say specifically not to use any other weights.

Now I have a hard time believing that the critical interal clearances are any smaller in the US engines than they are in the European engines, and because of this, I'm starting to believe that running a 40-weight oil, especially the 5w-40 synthetics, would be fine for even a new 2003 U.S. car/truck right off the showroom floor.

What do you all think of this?

Thanks,

Justin.

[ May 01, 2003, 06:52 AM: Message edited by: Justin ]

Justin · Apr 30, 2003

dagmando · May 1, 2003

When I was working in Switzerland a couple of years ago I was driving a VW Golf 1.6 for a few months and it called for 15w-40 oil. When you're at the gas station, everything is xW-40/50 synthetic and rarely did I see a 30wt oil and very little dino oil. I do not think I ever saw an oil additive either.

[ May 01, 2003, 05:19 PM: Message edited by: dagmando ]

WeyounDS9 · May 1, 2003

quote:

Originally posted by dagmando:
When I was working in Switzerland a couple of years ago I was driving a VW Golf 1.6 for a few months and it called for 15w-40 oil. When you're at the gas station, everything is xW-40/50 synthetic and rarely did I see a 30wt oil and very little dino oil. I do not think I ever saw an oil additive either.

Smart PPL those Swiss.
Almost like the Germans..

Fred..

TR3-2001SE · May 1, 2003

Owners manual for my car recomends 10w-30 for temp. above 100 F. Same car in Australia owners manual recomends 10w-40. Same car in Britain owners manual recomends 10w-40. It is almost the same engine as the intake manifold is slightly different and produces more power in Australia.
Exactly the same engine in Britain.
It has to be the CAFE. In Britain recomended change is at 9000 miles. In Australia recomended change is 6000 miles. In US it is 5000 for severe usage 7500 non-severe. I guess the British drive more conservative

One more thing in Britain and Australia the service manual says to adjust valves at 60,000
as we have solid lifters. No mention of valve adjustment in US manual. Also fuel filter change at 60,000 overseas. No mention of a fuel filter in US manual. Do we get cleaner fuel and just
don't need to adjust our valves? Better oil perhaps.

[ May 01, 2003, 06:45 PM: Message edited by: TR3-2001SE ]

Ken2 · May 1, 2003

One difference is that in many other parts of the world some 15W-40 and 5W-40 are gasoline engine formulations, not heavy duty diesel formulations. That may make a difference in the long run.

Ken

[ May 01, 2003, 06:51 PM: Message edited by: Ken2 ]

mormit · May 1, 2003

quote:

Originally posted by TR3-2001SE:
[QB] .I guess the British drive more conservative

[QB]

Nope. Been to the UK. They drive like they want to get somewhere.

The owners manual (printed in Sweden) for my 2002 Volvo calls for 10w-30 for temps no greater than than 86degF with 5W-40 being the reccommended viscosity for all temp driving.

The U.S. warranty book says 5w-30 up to 86degF and 10W-30 for all temps.

CAFE strikes again.

buster · May 1, 2003

quote:

Now I have a hard time believing that the critical interal clearances are any smaller in the US engines than they are in the European engines, and because of this, I'm starting to believe that running a 40-weight oil, especially the 5w-40 synthetics, would be fine for even a new 2003 U.S. car/truck right off the showroom floor.

The clearances are not any different and it is fine to run a 40wt. I posted the link to the New Zealand/Australian Mobil site and the same cars over there run 50wt. oils. It's all about MPG.

sprintman · May 1, 2003

buster just remember CAFE is a four letter word.

Al · May 1, 2003

One word: CAFE .I'm using 40 wt on two vehicles right now: Nissan Van (5W-40 Rotella syn) It's my son-in-laws and the van uses some oil-maybe a quart/4 K miles. He lives in N.C. and I'm not always there to watch over things

.

Also have Delvac 1 in my son's 2000 GrandAm. I'll be sending a sample in for analysis soon. This engine has the dreaded piston slap.

Justin · May 1, 2003

Thanks for the reply Al.

How do you like that Rotella-T Synthetic? I'm a big fan of the 15w-40 HDMO's, but I've never used one of the 5w-40 synthetics. If I went this route, I would probably go Rotella, as that is the only one available locally and readily available all around.

Might be getting a new vehicle in a little bit, and with most of them requiring 5w-30 and 10w-30, the 5w-40 HDMO seems a good way to go, giving better startup protection than my typical 15w-40 even in the summer. (Am I right on this????)

Dr. T · May 2, 2003

I've been saying this all along. 30 weight oils are for the birds...synthetic or otherwise. A3 rated ones are a good start, but I've moved on from these as well...40 weight should be a min...50's even better....for us oil guru's...the gen. public's a different story...

CJH · May 3, 2003

Other than Rotella T, what 5W40 Synthetic are out there (I know about Mobil ! 0W40)? Are there any 5W40s that are exclusively for gasoline engines?

G-MAN · May 3, 2003

quote:

Originally posted by Patman:

quote:

Originally posted by CJH:
Other than Rotella T, what 5W40 Synthetic are out there (I know about Mobil ! 0W40)? Are there any 5W40s that are exclusively for gasoline engines?

Click to expand...

Yes, Redline makes a 5w40, and Havoline does too (although that is group 3, not PAO)

Pennzoil, Quaker State, and Valvoline all make Group III synthetic 5w40.

Patman · May 4, 2003

quote:

Originally posted by CJH:
Other than Rotella T, what 5W40 Synthetic are out there (I know about Mobil ! 0W40)? Are there any 5W40s that are exclusively for gasoline engines?

Yes, Redline makes a 5w40, and Havoline does too (although that is group 3, not PAO)

ex_MGB · May 4, 2003

Can anyone point to oil analysis results showing lower wear numbers for xW-40 vs. xW-30? What I can see on the Oil Analysis Spreadsheet on maxima.org indicates higher wear in the VQ for the 40 weight

Perhaps American driving patterns (less public transport, more start-up and shutdown short trips) lead to a 30 vs. 40?

[ May 05, 2003, 06:05 AM: Message edited by: ex_MGB ]

Patman · May 4, 2003

quote:

Originally posted by ex_MGB:
Can anyone point to oil analysis results showing lower wear numbers for xW-40 vs. xW-30?

That's just it, there are a lot of people on here who claim that 40 and 50wt oils will result in lower engine wear, but have no proof to back it up. The best UOAs we've seen on here have typicallly been with 5w30 and 10w30.

buster · May 5, 2003

quote:

That's just it, there are a lot of people on here who claim that 40 and 50wt oils will result in lower engine wear, but have no proof to back it up. The best UOAs we've seen on here have typicallly been with 5w30 and 10w30.

Very true. I can't wait to see some 20wt UOA's. My friend who just bought the Vette and traded in his Mustang gave me 6qts of AMsoil 5w-20. If I don't use it in my wife's car, I am going to run it in mine, which calls for a 30wt. I want to see how it compares. I'm pulling a little Tooslick on this one.

JohnBrowning · May 5, 2003

Here is the way I see it. Added Viscosity is like extra ZDDP it does not really do anything to help you under normal counditions! It is under extreme's that it helps. If you drive like a little old lady on a nice sunday afternoon then 10W40,15W50,and 15W40 are not likely to help you out much. If on the other hand you tow, rock crawl, race, drive you car like you just stole it...... Then you will see a difference. If you operate in a hot enviroment like Ga., Tx., FL. and drive Hwy speeds for more then 40 minutes at a time .... you will see a difference. I would love to see someone drive coast to coast with motor craft 5W20 drain and sample then drive back with Redline 10W40. I would also like to see a car make it to 300,000 with a diet of nothing but motor craft 5W20!I am pretty sure that you would see a difference in the UOA. While all of the thin oil gurus ask for proof that higher vis. protects better they offer none to dispute the long standing recomendations of car manufactures, engine builders, and all of the older so called triboligist experts recomendation of thicker oils. It has only been the last 5 years that their has been any type of push for the use of thinner oil's. Let's do the math 70+ years of thicker oils protect better v.s. 5 years of thinner oils protect better. So far no one has been able to demonstrate what problem the 5W20 and 0W20 oils solve that was not able to be solved with 5W30,10W30 and 0W30 oils. I doubt that most people need to start their cars in -84 degree weather. This is just my opion backed by over 14 years as an ASE certified technician and a life time DIY'er.

sprintman · May 5, 2003

Best UOA's I've seen here were M1 0W40 in a Merc, Redline 5W40 in a turbo something and a 50W Castrol I think it was in another. A new Amsoil 10W40 UOA today pretty good too.

American vs. European / 30 vs. 40???

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