Volkswagen Dealer arguing with me over the color of 508 oil.........

Are we to think that if he puts in 508 that there will be problems? Certainly not. Reasons for recommending otherwise?
More overhead for fuel dilution is one reason. OP still being under warranty with a MY2019 proves that he doesn't rack up the miles, and likely short trips. OP also lives in NJ, with cold(ish) winters, further pointing to it being a good idea to have extra protection. Will it grenade at 100K after using 508.00? No. But you are kidding yourself if you think a 508.00 is the superior choice here.
 
How does it flow less volume when the oil pump is constant volume?

I still do not see any compelling technical reason to use a thinner oil. I just see a lot of made up notions that don’t hold true under examination.
Because. The oil pump is regulated. For the same gauge pressure, thinner oil flows more.
 
Because. The oil pump is regulated. For the same gauge pressure, thinner oil flows more.
That's only true for a PD pump with the relief engaged or a vane-style pump. With a conventional PD pump, where slip is a factor, when the relief isn't engaged, technically a heavier oil will flow more volume due to less internal bypass as a result of slip, but that's splitting hairs a bit there.
 
Pump that circulates coolant? Sounds kinda like the turbo timer I was talking about doesn't it?
No. Turbo "timers" that were popular in the 80s when turbos really started showing up, were add-ons that kept the engine running at idle for a certain programmed time with the ignition off and key removed. The after-run coolant pump is not time dependent, but rather temp controlled.
 
My first new car was a 1988 Dodge Shadow Turbo when I was 18 and I remember the turbo timer was a thing back then but I was in the habit of just sitting in the car an extra minute and letting it idle before shutting it off. I also tried to stay out of the boost for the last few minutes before arriving at my destination. That turbo still failed around 200,000 km though, but my sister had bought the car from me around 80,000 km.
 
Turbo timers! I wired up a few of those back in the late 90s through the mid 2000s.

Most of the CHRA of turbochargers from the 80s through 90s had oil cartridges and did not have coolant passages.
 
I have no idea what a turbo timer is. Modern turbos don't need a cool down period, you turn the car off and it has a secondary coolant pump that circulates coolant for about 5 min after shut down.
I'm not aware of any secondary pumps for the turbo. There are intercooler pumps, but that's not going to have any effect on turbo temp. Usually, flow is maintained after shutdown via thermosiphon.

No. Turbo "timers" that were popular in the 80s when turbos really started showing up, were add-ons that kept the engine running at idle for a certain programmed time with the ignition off and key removed. The after-run coolant pump is not time dependent, but rather temp controlled.
Yes they are temp controlled, but with a max time. It's the radiator fans. People are taking it literally. Turbo timer is a generic term because the function is the same. You'd notice all the ecoboosts out there idling after the driver gets out if it was literally a timer before allowing the engine shutdown. There are all sorts of implementations of protecting the integrated turbo.

turbo timer.webp
 
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I'm not aware of any secondary pumps for the turbo. There are intercooler pumps, but that's not going to have any effect on turbo temp. Usually, flow is maintained after shutdown via thermosiphon.


Yes they are temp controlled, but with a max time. It's the radiator fans. People are taking it literally. Turbo timer is a generic term because the function is the same. You'd notice all the ecoboosts out there idling after the driver gets out if it was literally a timer before allowing the engine shutdown. There are all sorts of implementations of protecting the integrated turbo.
Euro cars, and probably lots others, have had aux coolant pumps for decades to help with additional cooling loads and turbos after shutoff. They were much better than the timers because the engine did not remain running. Once manufacturers started plumbing coolant around turbo bearing housings, the problem with oil coking on a hot bearing was greatly reduced because oil as the sole cooling medium for a hot turbo bearing had limitations. This is what I just replaced on my car. The piping to it has an outlet and inlet that goes to the turbo housing.
https://www.fcpeuro.com/products/audi-additional-coolant-pump-pierburg-06d121601

I get where you're coming from with having some type of mechanism to cool the turbo after running. But "turbo timer" is not a generic term for us oldsters that remember them and the oil cartridges that filled and then dumped over the bearings after shutoff. I also remember sitting in the driveway letting my Merkur Xr4ti idle for a few minutes to let the turbo spin down and circulate oil. Yeah, radiator fans would run, but that provided little cooling to the turbo itself. Again, ancient tech. As @TiGeo mentioned, modern turbos don't need any special treatment like the snails of old with the advent of modern bearing materials, better oils and especially coolant cooled turbos. I suppose we can end this part of the discussion based on semantics. Back to the topic of green oil ;).
 
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My first new car was a 1988 Dodge Shadow Turbo when I was 18 and I remember the turbo timer was a thing back then but I was in the habit of just sitting in the car an extra minute and letting it idle before shutting it off. I also tried to stay out of the boost for the last few minutes before arriving at my destination. That turbo still failed around 200,000 km though, but my sister had bought the car from me around 80,000 km.
In the mid 80's I was a new Dodge Omni GLH owner. After a pretty wild highway run I parked the car in my apartment driveway, and proceeded inside. locked the front door but notice a strange orange glow coming from under the car. I quickly ran back out, popped the hood and saw that the turbo was red hot. I left the hood open and started the car and let it idle for 5 or so mins.
I do not recall if dodge used a water-jacketed housing or not. In any event, the turbine shaft is going to be very hot and can coke or gum the oil. It will likely steam the coolant and push it out for a couple mins.. Not as hot as a non jacketed unit but still worrysome.

If you were on boost moment before shut off, let the puppy idle. I even do this to let ex. valves and piston crowns cool on N.A. engines.
 
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In the mid 80's I was a new Dodge Omni GLH owner. After a pretty wild highway run I parked the car in my apartment driveway, and proceeded inside. locked the front door but notice a strange orange glow coming from under the car. I quickly ran back out, popped the hood and saw that the turbo was red hot. I left the hood open and started the car and let it idle for 5 or so mins.
I do not recall if dodge used a water-jacketed housing or not. In any event, the turbine shaft is going to be very hot and can coke or gum the oil. It will likely steam the coolant and push it out for a couple mins.. Not as hot as a non jacketed unit but still worrysome.

If you were on boost moment before shut off, let the puppy idle. I even do this to let ex. valves and piston crowns cool on N.A. engines.
I believe that my 88 was the first year that Chrysler started using a turbo that had coolant surrounding it, so if yours was prior to that, then it was definitely susceptible to getting more heat soak
 
How does it flow less volume when the oil pump is constant volume?

I still do not see any compelling technical reason to use a thinner oil. I just see a lot of made up notions that don’t hold true under examination.

It's also important to note (for the peanut gallery) that it's not just the turbo that's being cooled, the integrated exhaust manifold has coolant passing through it, the OEM cooling strategy is based entirely off of temps on the head. That's why these cars have several air to water heat exchangers and just a small coolant-fed oil cooler. Worrying about cooling from marginally more viscous oil is extremely silly.
 
As has been stated here/elsewhere, it was designed so that you knew visually it was 508 and woudln't accidently use it in a car that called for 502 or 504.
Yeah , sounds lame though doesn't it ?
Since containers are clearly marked , etc etc
 
There aren't other 0w20s at a VW dealer. And if it were the other way around, why isn't 504 0w30/5w30 dyed to make sure people don't get 502? Well, because 502 allows for 30 grade oils. No mechanical reason you can't use a 30 grade in a motor spec'd for 502.

OP is worried about nothing and you're going to get another thread locked.
I’m the OP and I’m “worried” about the lack of honesty from the dealer. I’d also love to know what exact oil is in my car at the moment because I don’t know since the dealer isn’t truthful.
 
I’m the OP and I’m “worried” about the lack of honesty from the dealer. I’d also love to know what exact oil is in my car at the moment because I don’t know since the dealer isn’t truthful.
Agree with your concern. One of the many reasons I do my own oil changes. Another option is finding a shop willing to use your oil and filter.
 
I’m the OP and I’m “worried” about the lack of honesty from the dealer. I’d also love to know what exact oil is in my car at the moment because I don’t know since the dealer isn’t truthful.
Fair, but it's a dealer, they're never honest. Only reason you go is to get the overpriced stamp on your service record.
 
I'm not aware of any secondary pumps for the turbo. There are intercooler pumps, but that's not going to have any effect on turbo temp. Usually, flow is maintained after shutdown via thermosiphon.


Yes they are temp controlled, but with a max time. It's the radiator fans. People are taking it literally. Turbo timer is a generic term because the function is the same. You'd notice all the ecoboosts out there idling after the driver gets out if it was literally a timer before allowing the engine shutdown. There are all sorts of implementations of protecting the integrated turbo.

View attachment 280508
Technical term is auxiliary water pump and it has been common in European vehicles since late 80’s when downsizing started there.
 
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