I've been thinking about it again and i feel like i want to try it at some point. AEHaas stated that his UOAs were fantastic up to 100k miles when he used PYB 5W20 in his 1994 S600. My engine is basically a third of the M120 engine in the S600 and shares the same dna but i'm sure the oil runs much cooler in mine.
Fuel prices are skyrocketing here and i'm more and more of an hypermiler. I have a very relaxed not to say sedate driving, i always drive on momentum and touch the brakes as little as possible, i also shift at lower rpms nowadays if traffic allows me to. I've been able to improve things even further by slightly over inflating my tires (Michelin Energy Saver) and carefully monitor how they wear, I removed as much dead weight as possible such as tools and useless stuff i used to cary around and i always keep my air filter clean.
60% of my driving is 60/65mph highway at 2500-2800 rpm, 40% is country roads at 1800-2300 rpm. Should my engine feel a little less sluggish and should i notice better mpg compared to the synthetic 5W40 i normally use?
Reasons i want/could try 0/5W20:
- See if i can get better gas mileage.
- See it throttle response is better.
- Unstressed engine, oversquare design (low piston speeds, lower bearing loads?)
- Small displacement, underpowered.
- 5.5L sump, the hottest oil temp i've seen was 90c after an extended italian tune up.
- Bearing clearances and width not different from other engines that use 20 weight oil.
The deterrents:
- My engine doesn't have those new low tension rings, no idea how much it comes into play.
- Very little or no UOAs on similar engines to have enough data.
- Low oil pressure?
- At operating temp 99%, maybe there won't be any difference at all compared to 5W40.
- Old valve steam seals?
- Leaks?
Feel free to give your opinion about this precise case and the relevance of me trying it without starting a thin vs. thick war!
Fuel prices are skyrocketing here and i'm more and more of an hypermiler. I have a very relaxed not to say sedate driving, i always drive on momentum and touch the brakes as little as possible, i also shift at lower rpms nowadays if traffic allows me to. I've been able to improve things even further by slightly over inflating my tires (Michelin Energy Saver) and carefully monitor how they wear, I removed as much dead weight as possible such as tools and useless stuff i used to cary around and i always keep my air filter clean.
60% of my driving is 60/65mph highway at 2500-2800 rpm, 40% is country roads at 1800-2300 rpm. Should my engine feel a little less sluggish and should i notice better mpg compared to the synthetic 5W40 i normally use?
Reasons i want/could try 0/5W20:
- See if i can get better gas mileage.
- See it throttle response is better.
- Unstressed engine, oversquare design (low piston speeds, lower bearing loads?)
- Small displacement, underpowered.
- 5.5L sump, the hottest oil temp i've seen was 90c after an extended italian tune up.
- Bearing clearances and width not different from other engines that use 20 weight oil.
The deterrents:
- My engine doesn't have those new low tension rings, no idea how much it comes into play.
- Very little or no UOAs on similar engines to have enough data.
- Low oil pressure?
- At operating temp 99%, maybe there won't be any difference at all compared to 5W40.
- Old valve steam seals?
- Leaks?
Feel free to give your opinion about this precise case and the relevance of me trying it without starting a thin vs. thick war!
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