FWIW, when I owned an '08 Audi RS4 Cabriolet w/4.2L V8 (420-hp) and an 8,000<!> rpm redline, on a cold start, a DIC warning popped-up with the message "Limit to 7,000 rpm until oil temp reaches 140F", and that engine has a 10-qt sump.
The importance of oil Temperature in Determining what Viscosity of oil to run.
- Thread starter Rand
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That’s not happening on a Toyota Hybrid. My Mercedes will hit operating temp in less than 10 minutes. Unless it’s 100 degrees outside ,oil temp never gets to 180 unless car has been on the freeway continuously for 15 minutes. Any stop and go driving, and the oil temp is down to 150-160 even after half an hour of continuous driving. I guess it’s good that excess energy isn’t wasted but excess heat is not produced. On a cold day, it could be 140 oil temp and then you have the decision to merge onto a freeway……. Here’s to thinking the power robbing Atkinson cycle is nicer to the engine and the engineers have designed the engine for longevity despite ongoing fluctuations in engine temperature throughout a drive.
The flip side is that… you could get some very long lasting oil at cooler temperatures with slow degradation if you apply the Arrhenius equation to oil.
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My giulietta manual says to drive carefully until the coolant temp needle moves off the stop (50°C).
My citroen Ax only said not to drive excessively in the red RPM zone during the break in period.
I wait until the coolant has stabilised, and then some.
the issue will be cavitation of the oil in the bearings
The M139 and K20C both spec 0w20 with the M139 holding the record of highest HP from a factory 2.0L 4cyl, running a closed deck and 27-30 psi from the factory pending if an S or not. (requires 229.71 at mercedes 10k intervals). Running a 20wt is appropriate pending what your manufacturer recommends. My M139 took a THRASHING before approaching 95c, with daily driving temps being 80c. MY K20 has only seen over 100c with sustained runs down a back straight and daily driving it sees 80-85c.
Stepping up a grade introduces unnecessary heat and friction, however I do err on the side of caution and will be running hpl supercar 0w20 this season with winter driving being an off the shelf 229.71.
Stepping up a grade introduces unnecessary heat and friction, however I do err on the side of caution and will be running hpl supercar 0w20 this season with winter driving being an off the shelf 229.71.
My M139 Amg and K20 would never see full throttle
Amg has a neat little indicator that makes the oil number blue "for cold" and after 167f it changes colors. The K20 doesn't have that but with integrated headers it hits 160f very fast.
wwillson said: "If my use was interstate all the time I would run HPL 15w-40 CC and get a viscosity of about 9.0 cSt, which is approximately the same viscosity as a 20wt at 100C."
^^^ He's saying that viscosity of 15W-40 at 250F is basically the same viscosity as xW-20 at 212F. That's why thicker oil should be used in applications where the oil temperatures get hotter than normal driving conditions - like heavy towing and track use cases.
This is the second time I’ve posted this comment today.
The 1st Gen Cruze 2.0 diesel and 2nd gen Cruze 1.6 diesel both required Dexos 2 or C3 5w30 in North America. This was a global platform which was offered with different diesel engines and emissions based on where they were sold. I am not an expert on what oil was used on every single engine that was offered in each region
The 1st Gen as sold 2014-2015 and 2nd Gen was 2017-2019. I believe they are good cars but failed due to lack of support from GM.
I have a Gen 1 Cruze, it has been solid for the last 50k miles however the TB had to replaced early because the WP seal failed rather dramatically. I have used various synthetic HD 10w30 oils in it since my ownership.
I test drove a new 2018 Cruze Diesel 6MT and I did not like it. The car drove fine, not as refined as a VW TDI but the interior was very disappointing. None of the optional interior upgrades were available in the sedan with manual transmission. It was a $25k car with the interior and electronics of a base model Cruze. The only negatives I’ve heard about the Gen 2 are emissions related, the manual transmission internal slave cylinder and rare timing chain issues. I would run 10w30 in it as well.
I regret not buying it as they were willing to sell it for $19k, which in todays money was a great deal.
Overall Opel and GM make good diesel engines which rival VW TDIs.
48 mpg on the highway with the 1.6 Diesel was achievable.
It was higher than 48. The 6MT sedan was rated at 52 MPGs on the freeway, and on long freeway jaunts under ideal conditions the manual sedan could approach 60 MPGs. The manual had significantly lower gearing than the 9 speed automatic and was high strung so more interior noise. I always wondered if you swapped the final drive from the Automatic into the Manual how it would effect FE.
The Gen 1 cruise with stock tuning was also capable of over 50 MPGs at moderate speeds. If calibrated with an EFI Live Ecotune, it’s even higher, mid to upper 50s with the Aisin AF40s high gearing. The Gen 1 was a bigger heavier car than the Gen 2 and the diesel came fully loaded including the z-link rear suspension not available in the stripped Gen 2 sedan.
Cruze Gen 1 and 2 were both great ideas, the Gen 1 was more refined and had more power but the Gen 2 6MT was the king of MPGs. GM did not advertise or market them so most people have no idea they even exist.
I didn't want to start another thread, so I'll post this here. This latest oil change I did for my vehicles, I switched my Jeep Grand Cherokee 5.7 V-8 over from 5W-20, (Pennzoil Platinum), to 5W-40 (Mobil 1 European Car Formula).
I've been running my 2018 Camry 2.5, 4 cylinder, that is stickered for 0W-16, on 0W-40 Mobil 1 for some time now. Neither of these vehicles ever see's "cold" startup temperatures under 60 F. And are regularly driven in 115 F+ desert temperatures during the Summer.
The first thing I noticed, is the 5.7 HEMI seems to be much quieter when idling with the 5W-40 oil at 200+F.... Much like my Toyota quieted down. I was leery to switch to a higher viscosity in the HEMI, because I've read it will cause the engine to throw codes with the MDS and VVT being sensitive to oil viscosity.
But the non high performance 6.4 HEMI they put in many of the Ram trucks, specifies 0W-40. So I can't imagine it becoming problematic in the 5.7.... Especially if not being driven in extreme cold Winter climates.
If the 6.4 HEMI can handle below freezing cold starts with 0W-40, the 5.7 should easily be able to handle 60F "cold starts" with the 5W-40.... Or am I wrong? I'm starting to believe this is all nonsense, much like the Toyota oil pumps are supposedly "programmed" for ONLY 0W-16.
Anyway, so far, so good. No issues whatsoever. The only difference I'm seeing is a slight increase in oil temperature. (From an average of 212 F max with 5W-20), to about 217 F with the 5W-40. And that's not scientific. Just my monitoring the oil temp when driving around town.
So my question is, are these VVT, MDS systems that viscosity sensitive? I've only driven the vehicle a bit over 200 miles since I went with the 5W-40. And as I said, so far so good. Not a single issue.
I've been running my 2018 Camry 2.5, 4 cylinder, that is stickered for 0W-16, on 0W-40 Mobil 1 for some time now. Neither of these vehicles ever see's "cold" startup temperatures under 60 F. And are regularly driven in 115 F+ desert temperatures during the Summer.
The first thing I noticed, is the 5.7 HEMI seems to be much quieter when idling with the 5W-40 oil at 200+F.... Much like my Toyota quieted down. I was leery to switch to a higher viscosity in the HEMI, because I've read it will cause the engine to throw codes with the MDS and VVT being sensitive to oil viscosity.
But the non high performance 6.4 HEMI they put in many of the Ram trucks, specifies 0W-40. So I can't imagine it becoming problematic in the 5.7.... Especially if not being driven in extreme cold Winter climates.
If the 6.4 HEMI can handle below freezing cold starts with 0W-40, the 5.7 should easily be able to handle 60F "cold starts" with the 5W-40.... Or am I wrong? I'm starting to believe this is all nonsense, much like the Toyota oil pumps are supposedly "programmed" for ONLY 0W-16.
Anyway, so far, so good. No issues whatsoever. The only difference I'm seeing is a slight increase in oil temperature. (From an average of 212 F max with 5W-20), to about 217 F with the 5W-40. And that's not scientific. Just my monitoring the oil temp when driving around town.
So my question is, are these VVT, MDS systems that viscosity sensitive? I've only driven the vehicle a bit over 200 miles since I went with the 5W-40. And as I said, so far so good. Not a single issue.
Cavitation is the result of a vacuum, correct? Bearings are pressurized by a positive-displacement oil pump. I can see the pump suffering cavitation if the oil cannot flow into the pickup fast enough, but bearings… I may be wrong, but I don’t see how one would get vacuum under any circumstances at the bearing. The oil system has positive atmospheric pressure at both the pump inlet and the bearing outlet, which means the only way to effect flow is via the work of the PD pump. You may get oil starvation or aeration at the bearing, sure. And neither of those are conducive to bearing life.
https://www.machinerylubrication.com/Read/30768/cavitation-or-aeration
Wasn’t the 1983 VW Rabbit diesel also capable of 50+ mpg? Some use this 40 years of technology has brought us… and yes, I’d put the Cruze on the same quality level (or even below) what the Rabbit was in its time. The 1983 Rabbit was also the first vehicle to have auto stop/start technology.
I had a 1979 VW Rabbit diesel. I got an honest 50 MPG with it, the entire time I had it. I had a 10 gallon auxiliary fuel tank installed . I could easily drive non stop from Chicago, to visit my dad in Houston, when I filled both to the top.
Mine was a 4 speed stick. The downside is it only had 48 H.P., and couldn't get out of it's own way.
Mine was a 4 speed stick. The downside is it only had 48 H.P., and couldn't get out of it's own way.
Those little MK1s weigh less than 2000lbs. I had a friend in Germany that swapped in a 12v VR6 and it would do stoppies.
I'm getting 41mpg in my MK5 Jetta now.
I wish my Toyota 2grfe had an oil temp readout. I'm currently using 0w40 and it may be impacting my mpg more than I think.
Compared to what other grade? It’s about a 1% to perhaps 2% fuel consumption difference between grades.
OVERKILL
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No, the system is not that sensitive, most of the parts are identical between the 6.4L and the 5.7L and of course 5W-20 at -30 is a heck of a lot heavier than your 5W-40 at any temperature.
edyvw
$50 site donor 2025
I never noticed difference.
Oil temperature in 2gr-fe in Sienna will be around 220-225. It is coolant temperature that takes forever. My wife called Sienna “ice box.”
I'm assuming my engine oil runs at 250F/121C. Hard to know without a temperature gauge. 6 cSt vs 9 cSt at 120C comparing to 0w20 and my 0w40. If my engine runs cooler then the cSt difference is greater. What I don't know is the horsepower draw of the oil and pump at those viscosity numbers. You are quoting 1-2% between grades, so maybe 2-4% in my application and assumptions?
Plus the fact that fuel consumption in everyday driving varies a great deal due to may factors other than the oil. In fact, to see a difference in the oil requires a laboratory test where all those variables are kept constant except for the oil. But it’s still there so it does exist.
The HT/HS of that oil is relatively benign for a 40-grade so it’s likely in the lower range for an estimation.
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