What is the difference between SP and SN engine oil grades?

[SanMaggie]

The differences between SP and SN engine oil grades are as follows: 1. Viscosity level (phosphorus content): SN oil has relatively lower phosphorus content; and in terms of viscosity comparison between SN and SP, SP has a slightly higher viscosity value. 2. Different advantages: SP oil provides a stronger oil film than SN, offering better protective performance. Additionally, SP shows stable improvements over SN in terms of noise reduction, fuel consumption, and acceleration performance. Methods for selecting engine oil are as follows: 1. Choose the appropriate oil based on engine type: Naturally aspirated engine models can use mineral oil, which fully meets the needs of such engines. Turbocharged engines should opt for semi-synthetic or fully synthetic oil to better protect the engine. 2. Select according to oil specifications: Since each car brand's engine is different, the easiest way is to refer directly to the vehicle's manual, which provides the most standard and accurate method.

[DiAddyson]

Recently I've been researching engine oils. Both SP and SN are API standards, but SP is newer. Released in 2020, SP is specifically optimized for modern engines. For example, SP oil can better suppress low-speed pre-ignition (LSPI) issues common in turbocharged direct-injection vehicles, protecting the engine; whereas the SN standard from 2010 didn't account for this. SP also has better oxidation resistance, reducing sludge formation and extending maintenance intervals. Additionally, SP offers better fuel economy, saving about 2% on fuel, and has lower phosphorus content, which is gentler on catalytic converters. If your car was purchased within the last five years, especially if it's turbocharged, SP would be more suitable.

[LeArianna]

I've tried different engine oils in both of my cars. SP grade is clearly more suitable for modern engines than SN, especially for direct injection vehicles. When using SN before, the engine would occasionally shake after high RPMs, but this issue disappeared after switching to SP. The main differences lie in three aspects: SP offers improved wear resistance, providing better protection for vulnerable components like piston rings and camshafts; it has stricter oxidation resistance standards, extending oil life; and a minor detail - SP is more compatible with particulate filters, resulting in cleaner emissions. Although SP is slightly more expensive, it's worth it overall. While older cars can still make do with SN, new car owners are advised to go straight for SP.

[VonSamantha]

Let's briefly talk about engine oil grades. The biggest difference between SP and SN lies in protection capability: SP introduces a new test standard called Sequence IX, specifically designed to prevent knocking in small-displacement turbocharged engines—a feature SN lacks. SP also enforces stricter phosphorus content control to better protect exhaust systems. In practical terms, SP makes engines run quieter, reduces cold-start wear, and is particularly suitable for northern winters. We recommend owners check their manuals—most post-2020 models now recommend SP. While SN is still usable, its performance lags significantly behind.

[SanLaila]

As a frequent long-distance driver, my real-world tests show that SP-grade oil is more fuel-efficient than SN. Under the same road conditions, it saves about 0.3L per 100km due to higher lubrication efficiency. Technically, the upgrade mainly focuses on preventing low-speed pre-ignition and resisting deposits. SP-grade oils use improved detergent dispersants, keeping piston undersides cleaner. In terms of emissions, SP has about 15% lower sulfur content than SN, making it more environmentally friendly. Currently, most mainstream full-synthetic oils meet SP standards with minimal price differences. Remember to choose SP oils with ILSAC GF-6 certification for better compatibility.