TheSamba.com :: View topic - Official "What oil / additives should I use" topic

Thu Mar 14, 2024 2:55 pm

It's now march 2024. I'm in the US, last time was 2 years ago when I barely got a chance to just start our van and drive around the parking lot. In other words, won't hurt to change the oil.
Looks like the local Walmart only has 5w20 which I think is way too thin. Condition of the 1600 engine is unknown, so I'd rather stick to the usual viscosity. 15w50 or 20w50. What are my options here? Off the shelf rather than ordering.
Thanks!

Sun Mar 17, 2024 6:16 pm

A stock Beetle engine was designed to use straight 30 oil. Today, use 5W-30. It's available everywhere.

20W-50 tar is for worn out engines. It also causes your engine oil to run much hotter than it would with 5W-30.

Mon Mar 18, 2024 8:09 am

Interesting you say this. I have the original manual to my French bus (1600cc upright engine) and their recommandations are different from yours:

They do recommend SAE30 but the temperature window is pretty narrow. And they recommend multigrade too, and it's 15W50. They even emphasize that using 5w20 should be done with caution especially if the outside temp is above their recommandation.
So I think 20w50 in an old engine is probably not a bad option. And I just got some VR1 Classic (or whatever it's called) and it should be fine. :D

Mon Mar 18, 2024 10:40 am

The problem with a really thick oil is that the VW aircooled engine regulates oil temperatures by sensing oil pressure and anything you do in an attempt to get higher oil pressure the engine will try to counter by letting the engine oil get that much hotter.

Oil that is bypassing the cooler and being dumped back to the sump doesn't cool the bearings and pistons, and doesn't otherwise help with lubrication. The rule of thumb is you want 10 psi per thousand RPM with want ever oil you are running.

I have been able to run every aircooled VW engine I have owned on 30wt regardless of the miles on the engine with one rebuild giving me ~250K miles. For winter driving I have been able to start any engine I have owned down to -20°F on 10w30, though in more recent years I run a 5w40 year around, though I am moving my Arizona vehicles to 15w40 Rotella T6 as it still carries an "S" rating, we will have to see how that works.

Note that the reason VW didn't recommend that multigrades be used at higher ambient temperatures is because the multigrades of the time broke down slowly in use, with high the high temps of the VW engine accelerating the process. There are notes in the VW manuals for several years saying multigrades are not recommend, but we are not running SC and SD oils any more so that doesn't apply as much today.

Still best to run a synthetic in my mind as they are less bothered by the heat.

Mon Mar 18, 2024 2:04 pm

My other bus (in France) runs on 15w50 Motul 300V. It's the best thing available in Europe - totally overkill for a mildly modified engine but hey, love has no boundaries. It's a synthetic oil meant for older racing cars. So it deals very well with heat transportation unlike most regular synth oils.
Bus has an oil gauge and it sits at 3 bars at 55mph cruising speed - roughly 3000rpm. So perfect recommended pressure. And it never goes above 95°C.
I've seen people running this oil in over heating engines at 120°C+ without losing any pressure unlike other oils.
I'll probably end up adding a gauge to the US bus. Pressure is almost more important than temperature.

Thu Apr 04, 2024 8:41 am

pierrox wrote: Interesting you say this. I have the original manual to my French bus (1600cc upright engine) and their recommandations are different from yours:

They do recommend SAE30 but the temperature window is pretty narrow. And they recommend multigrade too, and it's 15W50. They even emphasize that using 5w20 should be done with caution especially if the outside temp is above their recommandation.
So I think 20w50 in an old engine is probably not a bad option. And I just got some VR1 Classic (or whatever it's called) and it should be fine. :D My problem with that chart is that 68F is considered tropical... that, and oils have changed a great deal since that was printed

Thu Apr 04, 2024 1:09 pm

This is the chart in the owner's manual for a 1970 model. For general use VW recommended 20w20 up to 68°F and 30wt for warmer temps. Their oil pressure recommendation is set using 30wt at ~160°F, where you should see a minimum of ~10 psi per 1000 RPM. Note that today's oils are a vast improvement over the oils of 1970 giving longer life with more resistance to heat degradation, with a straight 30wt giving similar performance to a 15w30 synthetic.

Wed Apr 17, 2024 9:14 am

scottyrocks wrote: Okay, so I actually finally read all 232 pages (okay, call me a glutton for punishment], and the most important information, afaic, came from this link:

https://540ratblog.wordpress.com/2013/06/20/motor-oil-wear-test-ranking/

so that, most of all, made this thread a worthwhile (re]read.

This blog has been mentioned here a number of times, and summarized very well a few pages back by @Lingwendil.

540 RAT, the writer of the linked blog, in addition to having a bunch of credentials and practical experience, bases his writings on scientific experimentation. It also makes a lot of sense. My comments, below, are based on the blog, and his scientific testing, in particular. For further details, see the blog.

The blog presents the oil selections in a ranked list, which appeals to one's sense of making a quality choice, spurred by the never ending quest for the 'BEST'. I realize that there is much debate surrounding ZDDP additives and testing methodologies. Perhaps the most interesting aspect the author drives home is during the quick reference / introduction and recommendations in section 37 for air cooled vehicles:

540 Rat wrote:
– Water cooled engines are capable of controlling their oil temperatures under normal operating conditions, which can allow using thinner oils, if following the recommendations just above.

– Air cooled engines cannot control their oil temperature reliably, and should use an oil with a HOT viscosity rating of 50 or 60.

Motor oil becomes thinner and thinner, as its temperature becomes hotter and hotter (it does NOT get thicker as it gets hotter, as some people mistakenly believe, due to their confusion over the labeled viscosity ratings). As oil becomes hotter and thinner, the oil pressure and the oil’s wear protection capability DECREASE. So, using a thick oil in air cooled engines to begin with, prevents the oil from becoming so dangerously thin under extreme conditions, that it could damage the engine. In other words, using thick motor oil in air cooled engines, provides a higher margin of safety.

SUMMARY/CONCLUSION:
In air cooled engines, I recommend using thick hot rated motor oils such as 5W50, 10W50, 15W50, 20W50, 10W60 or 15W60 for the best engine protection.

Wed Apr 17, 2024 12:49 pm

kimkinzie wrote: scottyrocks wrote: Okay, so I actually finally read all 232 pages (okay, call me a glutton for punishment], and the most important information, afaic, came from this link:

https://540ratblog.wordpress.com/2013/06/20/motor-oil-wear-test-ranking/

so that, most of all, made this thread a worthwhile (re]read.

This blog has been mentioned here a number of times, and summarized very well a few pages back by @Lingwendil.

540 RAT, the writer of the linked blog, in addition to having a bunch of credentials and practical experience, bases his writings on scientific experimentation. It also makes a lot of sense. My comments, below, are based on the blog, and his scientific testing, in particular. For further details, see the blog.

The blog presents the oil selections in a ranked list, which appeals to one's sense of making a quality choice, spurred by the never ending quest for the 'BEST'. I realize that there is much debate surrounding ZDDP additives and testing methodologies. Perhaps the most interesting aspect the author drives home is during the quick reference / introduction and recommendations in section 37 for air cooled vehicles:

540 Rat wrote:
– Water cooled engines are capable of controlling their oil temperatures under normal operating conditions, which can allow using thinner oils, if following the recommendations just above.

– Air cooled engines cannot control their oil temperature reliably, and should use an oil with a HOT viscosity rating of 50 or 60.

Motor oil becomes thinner and thinner, as its temperature becomes hotter and hotter (it does NOT get thicker as it gets hotter, as some people mistakenly believe, due to their confusion over the labeled viscosity ratings). As oil becomes hotter and thinner, the oil pressure and the oil’s wear protection capability DECREASE. So, using a thick oil in air cooled engines to begin with, prevents the oil from becoming so dangerously thin under extreme conditions, that it could damage the engine. In other words, using thick motor oil in air cooled engines, provides a higher margin of safety.

SUMMARY/CONCLUSION:
In air cooled engines, I recommend using thick hot rated motor oils such as 5W50, 10W50, 15W50, 20W50, 10W60 or 15W60 for the best engine protection.

On a stock VW aircooled engine, the oils he recommends are certainly going to make it so one doesn't have control over oil temperature as at highway speeds the oil is going to be bypassing the cooler.

Wed Apr 17, 2024 1:27 pm

I always thought (perhaps wrongly) that he was talking about a lawnmower engine, or a motorcycle air cooled engine, that did not have an oil cooler. I may be wrong there though.

Wed Apr 17, 2024 7:17 pm

soissisc wrote: I always thought (perhaps wrongly) that he was talking about a lawnmower engine, or a motorcycle air cooled engine, that did not have an oil cooler. I may be wrong there though.

That would make more sense.

Sat Apr 20, 2024 1:40 pm

Wildthings wrote: soissisc wrote: I always thought (perhaps wrongly) that he was talking about a lawnmower engine, or a motorcycle air cooled engine, that did not have an oil cooler. I may be wrong there though.

That would make more sense.

I became interested in viscosity ratings after bringing a 1997 air-cooled Porsche 911 back to life from a 12 year slumber. The vehicle was mothballed due to expensive valve cover leaks that required an engine-out repair. BR Racing in Los Gatos did this work, and in the process switched the engine oil from Mobil 1 0w40 synthetic oil (recommended on engine sticker) to Motol 20w50 conventional. They indicated that there was much racing success with this approach, especially in the area of temperature control.

My presumption is that @420Rat was talking about aircooled Porsche vehicles as well as motorcycles, in our case extrapolating it to flat-4 VWs. His recommendation seems inline with much research that seems to indicate that higher viscosities are beneficial for piston ring seal at operating temperatures. This video below does a lot to dispel myths associated with higher weight oils:

Sat Apr 20, 2024 8:54 pm

kimkinzie wrote: Wildthings wrote: soissisc wrote: I always thought (perhaps wrongly) that he was talking about a lawnmower engine, or a motorcycle air cooled engine, that did not have an oil cooler. I may be wrong there though.

That would make more sense.

I became interested in viscosity ratings after bringing a 1997 air-cooled Porsche 911 back to life from a 12 year slumber. The vehicle was mothballed due to expensive valve cover leaks that required an engine-out repair. BR Racing in Los Gatos did this work, and in the process switched the engine oil from Mobil 1 0w40 synthetic oil (recommended on engine sticker) to Motol 20w50 conventional. They indicated that there was much racing success with this approach, especially in the area of temperature control.

My presumption is that @420Rat was talking about aircooled Porsche vehicles as well as motorcycles, in our case extrapolating it to flat-4 VWs. His recommendation seems inline with much research that seems to indicate that higher viscosities are beneficial for piston ring seal at operating temperatures. This video below does a lot to dispel myths associated with higher weight oils:

VW engines are designed to provide the oil viscosity they need be allowing the oil to bypass the cooler until the viscosity drops to what the engineers wanted. Use thicker oil and the engine just lets the oil get hotter and hotter until the viscosity gets low enough. Oil that is dumped to the sump without going through the cooler does not tend to carry the heat away from the bearing and pistons very effectively either.

If you have loose bearings and need 20w50 to get the oil pressure up to spec, that is one thing, but if you oil pressure is fine using 5w30 then there is no gain to running thicker oil. Interesting I just got a new engine for my riding mower today and looked at the oil recommendation. The chart showed that either STRAIGHT 30wt or 5w30 SYNTHETIC was good to above 104°F, though they are probably not thinking of the 115°+ that is common here on summer afternoons. They mention that 5w30 and 10w30 DINO oils may not be able to handle ambient temperatures in excess of 80°F without an increase in oil usage.

Fri Apr 26, 2024 4:28 pm

recently resurrected a 1600 DP that had been sitting out in the weather for many years. The sludge in the crankcase and rocker arms was horrendous. I tried MO and diesel oil as a flush but it had little effect at all. So I filled it up with the supertech and done 3 oil changes over 1500 miles. Yesterday I pulled the valve covers to check valve lash. What I saw blew me away! Shiny,like new aluminum heads and clean rocker arm assemblies.

Fri Apr 26, 2024 4:46 pm

Schatzievw wrote: recently resurrected a 1600 DP that had been sitting out in the weather for many years. The sludge in the crankcase and rocker arms was horrendous. I tried MO and diesel oil as a flush but it had little effect at all. So I filled it up with the supertech and done 3 oil changes over 1500 miles. Yesterday I pulled the valve covers to check valve lash. What I saw blew me away! Shiny,like new aluminum heads and clean rocker arm assemblies.

Pictures...?

Fri Apr 26, 2024 4:49 pm

My concern is, does all of the sludge flush out the strainer plate or does some get into the oil cooler and oil passages and cause a blockage.

Sun Jun 16, 2024 5:23 am

HELP - Whodathunk choosing oil would lead to several hours of reading & a headache?

Hello o' wise members of The Samba. Following several hours of reading, I am more confused then when initially the thought crossed my mind..."hey I should change the oil in my newly acquired classic beetle...can't be too difficult right?"

Some particulars:
1971 Volkswagen Super Beetle Sedan 113
Where its lived: Iowa (Feb 1971), Illinois (1994-2006 DD)(2006-2023 Stored), Indiana (2023-present)
Climate: Midwest/Humid Continental Climate (Köppen ca. 1900)
Driving Season: Late Spring to Early Autumn
Temperature Range: 41F to 99F

My Super Beetle has approximately 63,000 original miles and ZERO oil leaks at present. Thus my question is, if the manual describes a straight-grade SAE 30 as the proper oil for the above temperature range, could one simply use what is now considered a 'break in oil' such as DRIVEN's "GP-1 30 SAE Grade Specialty Break In Motor Oil?"

Quote: WHY ARE YOU LOOKING AT DRIVEN GP-1 Specialty Break-In? It appears to be one of the few conventional straight-grade motor oils with appropriate levels of ZDDP left on the market

It appears to contain >1000 Zinc & Phosphorus [ZDDP], which is above the claimed minimum necessary for the flat tappet style camshafts, is a conventional motor oil, and low detergent so as not to disturb the 53 year old engine seals.
Quote: The above statements pertaining ZDDP & low detergent/seals were NOT evaluated by the FDA, but instead gleaned from posts by users made across several message boards such the Samba, Bob the Oil Guy, and Classic Motorsports.

My working hypothesis, based largely from 20+ years in IT datacenter environments is: if the manual says X then use X, not the newer & 'improved' Y as it likely ignores/unaware of specific engineering considerations when X was originally manufactured, which in this case would equate to Y being the synthetic multi-grades in the marketplace.

Nevertheless, certainly open to and looking for some real world guidance from the board.

Danke.

Sun Jun 16, 2024 11:03 am

Allie_Gator wrote:
My working hypothesis, based largely from 20+ years in IT datacenter environments is: if the manual says X then use X, not the newer & 'improved' Y as it likely ignores/unaware of specific engineering considerations when X was originally manufactured, which in this case would equate to Y being the synthetic multi-grades in the marketplace.

Straight weight oils are not required to have reduced ZDDP nor are any oils with either number being above 10w30,such at a 10w40 or 15w30 (if you could find it). There is no rule that a 30wt, or 10w40 oil has to have more than a certain minimum though, at least to the best of my knowledge. I buy my straight weight oil from the local farm supply who carries the CENEX brand, their 30wt contains 1100 ppm zinc.

The zinc level is not as important as it was when the SM spec first came out, as the ZDDP being added today is less volatile than that used 20+ years ago so it does burn/evaporate as readily and most oils also have significant amounts of other anti wear additives.

Both straight weight oils and synthetic oils can handle heat better than a dino multigrade, so I see little reason to run a dino multigrade especially where it gets above 90°F during the summer months. I ran straight 30wt in my engines for decades during the summer and my engines lasted very well, even when I was doing 5000' climbs daily to get to work. In my '77 Transporter with an 1800 Type 4 engine I run 5w40 synthetic these days while in my '73 Thing I am running straight 30wt. Our local Walmart has both a 5w40 Mobile 1 Diesel oil (1300ppm zinc) that also carries a SN rating and a 5w40 Mobile 1 European Formula oil (1100ppm zinc).

If you could find an SD oil from when this engines were new, you would not be happy with it in the long run as the level of protect would be dismal compared to today's oils. Having 0.010 or more taper to the cylinders at overhaul time was common 50 years ago, while when I pulled down my circa 1990 rebuild a few years back (250K miles) I had zero taper and could still see the honing marks right at the top of the ring travel, the point of maximum wear.

Sun Jun 16, 2024 2:05 pm

I wonder about the Castrol full synthetic 5-40 Euro Car , that meets VW spec for "modern" (this century at least) VW oil spec for the 2.0T, which has the flat tappet high pressure fuel pump and cam follower. The first generation 2.0T had a pretty extreme cam profile driving the fuel pump.

I know they say that conventional oil moves the heat better than synthetic, but synthetic reduces heat. I am just throwing it out there as I use that oil for a few Audi's with 1st generation 2.0T in the household here. I feel like the turbo introduces an abusive amount of heat to the oil also.

I am getting close to firing up a recent rebuild and have been thinking about oil as I have been away from the aircooled engine for a few years.

Sun Jun 16, 2024 4:28 pm

The 2.0T FSI was/is notorious for eating the HPFP follower. I was regularly replacing mine preventively. And I was using the VW approved oil and I still saw high wear.