Emailed RP regarding basestocks on SN oils.

[buster]

It all boils down to "there is no best oil". Formulating often requires trade-offs. Some oils do some things better than others. That's all it comes down to really.

To many apples/oranges comparisons. Comparing Redline and Amsoil to TGMO and Mazda 0w20 is pointless.

Redline is more of a racing oil so why would they use a lot of VM'ers if shear stability is their goal?

Amsoil is designed ultimatley for long drains...same thing applies.

TGMO/Mazda 0w20 etc. are designed for daily drivers and maximum fuel economy.

What's the issue here?

 

[aquariuscsm]

RP had told me a few years back,that their Synerlec oils were Grp IV base with Synerlec being a Grp V additive,and a small amount of Grp II (as a carrier).

 

[A_Harman]

demarpaint,

The thing is, if an oil has earned the API starbust and service symbols, it has passed a standard battery of engine tests and has been proven to provide adequate wear protection. Remember that the high VI only affects ambient and low temperature startup performance. A 0w20 will have the same HTHS viscosity as a 5w20 at extreme operating temperature and will give the same protection.

 

[Trav]

Frank, the only engine tear down i have done that is worth a pee hole in the snow was on my own water cooled DOHC L4 1000 cc bike engine.
I say that because i was the only rider and it only used one brand and weight oil and OEM filter its entire life except for the first 1K and is still on the "Red" Castrol to this very day with the new owner.
The bike is now 20 yrs old and the RS is not "red" any longer but its the same minus the dye.
I kept perfect records of every service and OCI.

I bought it in 92 in the crate and picked her up in Holland to avoid the 100HP limit imposed by the Germans at that time, the bike was grey market, it had 145 HP.
It had 2 tenths on the clock which i assume was from testing at the time of manufacture.

As the years went by i bought bigger and faster bikes but always kept this one as i loved to ride it, it wasn't over powered and the top speed was still decent. At 270 Kmh it ran out of wind.
0-100 Kmh (62 Mph) times were okay at 3.3 sec. I mention these because after the tear down and 12 yrs and 240K later the performance remained the same.

I changed the oil and filter 3-4 times in the first 1K.
Then i did the 1K service and meticulously adjusted the valve clearance and balanced the carbs. Some valves were slightly tight and a few were loose.
At that point it got its first dose of Castrol RS 10w60 (it was spec for 10w30in Holland 10w40 Germany) but the Castrol dealer convinced me this was the best oil on the market bar none, i bit and used it.

The bike ran year round except when there was snow on the ground (not very often where i was)in temps from +38 to -5c.
some around town use, quite a few short trips and a lot of autobahn use up to 9,000 RPM sustained so it saw a good range of operating conditions.

I checked the valves every 10k for the first 50K but they never needed adjustment, i then did it every 25K and still needed nothing so i didn't bother any more.

At approx 200K the cam chain was stretched out pretty good to the point it made noise cold so i decided to tear it down to get the crank out.
I decided on a rebuild if everything is going to be open anyway.
The bearings, pistons, rings, cams, crank, OP, and all other internals were all well within new OEM specs (i used the FSM for the values). There were zero scratches in any bearing.
The engine was spotless inside, it never used any oil and i never used any sort of additive in it just the RS.
Oil pressure was OEM new at 100 PSI at idle and 130+ at 12,000 rpm (op sensor triggered at 92 psi.

I put the new chain in with a new OEM gasket and seal kit and used all the original parts in their original locations, no issues.
I kept it to 240K and sold it 05 only because i had 2 other bikes and was coming to the States. I didn't want to leave 3 bikes behind at the house no running till i come home.

I saw the old girl last month and the guy that bought it still uses the RS and it now has over 300K on the clock. He says it runs like a champ and has needed no engine work.

Interestingly the Honda dealers claim on average these engines were good for about 100K before they were finished.

This engine goes against everything BITOG.
Multiple OC within the first 1K (all the bearings were scratch free)
It ran and continues to do so on high HTHS thick oil year round.

IMHO this is a good valid test of this oil, the engine only ever used this one brand and weight of oil with OEM filters.
I never saw even a qt of any other oil after initial break in for which i used a cheap conventional 15w40.
My OCI was 5K.

This engine is now over 20 yrs old (it was 20 march 23 2012)
and still providing impeccable service despite the high HTHS oil.

 

[Jim Allen]

I have a similar anecdotal story to Trav's.

I bought an '86 F250 diesel with just a few thousand miles on it. In '87, it got a Banks turbo kit which increased the horsepower from 170 to 250 and torque from 315 to 500 lbs-ft (OE vs Banks ratings). The truck was primarily used to tow a variety of travel trailers and/or haul overhead campers. At first I used the recommended 10W30 SF/CC oil (Pennzoil) then I used either 15W40 or 10W30 Rotella-T (the 10W30 was harder to find in the early days so I got what I could get) or DELO oils. Looks like about 60 percent of the time, it had 10W30 in it. Most often, the filters were the Motorcraft FL784 but in the late '90s, I started using the larger FL1995 Power Stroke two quart filter, which is also more efficient.

I finished an overhaul of that engine earlier this year, mostly due to a major head gasket failure (turbo related... 10-14 lbs boost on a NA engine with a 21.5:1 CR and weak head bolts). Anyway, at 140K miles, the bores had .001" or less taper and the crank miked and looked perfect. The rod bearings had some cavitation marks on the upper shells (not unexpected because of the added turbo) but because the overhaul was tied in with a story, I had access to several engineers who looked at the bearings and suggested I reuse them (I didn't, though). So 60 percent of the time I was using an oil lighter than recommended, in mostly hard use, and yet the lubrication related part of the engine was nearly perfect, despite the power having been increased almost 50 percent and torque by 45 percent. In all fairness, I must say that the 6.9L was originally spec'ed for a 30 grade but in '86, the recommendation changed to 15W40.

 

[demarpaint]

Originally Posted By: Jim Allen
It all boils down to as thin as possible as thick as necessary, doesn't it?

In some places and with some vehicles, meeting that basic requirement might be a XW40 or XXW40. In other places and with other vehicles, it might be a XW20. I think it's a mistake to assume that one end of that scale is automatically better than another without considering all the individual factors. These would include the engine, the operational conditions, climate and the particular oil being used.

In truth, most engines will operate well, or well-enough, within a broad range of viscosities. That's the saving grace for all those standing on either of the thick or thin soapboxes. You really have to go radically outside the box to reach a sub-optimal condition where bad results are immediately noticeable. That optimal viscosity point is still there for every engine, but it's dancing around depending on the individual conditions.

What's the optimal viscosity point? IMO, it the point at which efficiency and protection converge for a particular engine in its operational situation.

We can take a lot of clues from the OEM recommendations, no matter which part of the world they come, if we look at the prevailing conditions in that region. But "clues" aren't always gospel at either end of the scale and saying one is universally better than another is silly.

A lot of testing has been done, is being done, to validate the thinner oils. From what I've seen, more testing has been done in that direction than to prove heavier oils are "better." That's probably as it should be, since thick oils are the "no brainer" choice. If you don't care about efficiency, that's a safe direction. Going thinner requires more care and better oils.



I agree with everything you're saying, however here's an example that throws a monkey wrench into the works. My 08 Liberty only calls for 5W20 oil, no other options. In other parts of the world with similar climates to the USA they have other options for the same identical engine. In the US if I fail to use 5W20 and decide to try 0W30 I could very well have a warranty problem should something go wrong. If I move to OZ I can select the grade of oil based on how the vehicle will be use and the climate, and maintain a warranty if I bought the vehicle there.

 

[Jim Allen]

Well, the warranty thing is a separate issue for discussion. Plus, it isn't likely the 5W20 is harming your Jeep so you have no real need to change, just a want. If you do, you know the potential consequences. Nanny state. Nanny carmaker. I dislike them both.

 

[CATERHAM]

Originally Posted By: Jim Allen
Well, the warranty thing is a separate issue for discussion. Plus, it isn't likely the 5W20 is harming your Jeep so you have no real need to change, just a want. If you do, you know the potential consequences. Nanny state. Nanny carmaker. I dislike them both.

Right, the warranty is a separate issue and it really is a matter of interpretation when a company specifies a 5w20 conventional.
Mobil is on record stating that their AFE 0W-20 can be used in any application for which a 5W-20 is specified without voiding the warranty.
The other argument that I agree with is that the synthetic API 0W-20 exceeds the requirements of the 5W-20 grade therefore it meets warranty requirements.
What leaves some owners uncomfortable is that if you ask a customer service rep' (who of course knows nothing about motor oil) if you can use a 0W-20, the answer will always be no.
Of course the more pertinent question is, has a warranty claim ever been denied because one used a 0W-XX oil instead of the spec'd 5W-XX oil, and I believe the answer is also no.
So at the end if the day it really comes down to what you're personally comfortable with.