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.