Difficulty in starting at low temperatures in winter is more than 60% related to improper selection of oil viscosity. Scientifically matching SAE labels can keep the car starting smoothly at -30 ℃. The following are oil selection schemes and technical principles for different climate zones:

1、 The culprit behind the difficulty in starting at low temperatures: engine oil solidification

When the temperature drops sharply, ordinary engine oil will turn into a "butter like" state:

-At 20 ℃: The viscosity of 10W-40 engine oil reaches 15000cP (exceeding the pumping limit by 3 times)

Cold start instantaneous wear accounts for 75% of the total engine wear (SAE research data)

2、 The Golden Rule for Choosing Winter Engine Oil

1. Understand SAE low temperature label (number before W)

label

Applicable minimum temperature

Maximum pumping temperature

Representative Region

0W -35 ℃ -40 ℃ Heilongjiang/Inner Mongolia

5W -30 ℃ -35 ℃ Beijing/Liaoning

10W -25 ℃ -30 ℃ Jiangsu Zhejiang/Hubei

Technical truth: 0W-20 has 6 times faster flowability at -30 ℃ than 10W-40 (ASTM D5293 test)

2. Adaptation plans for different vehicle models

engine type

Recommended winter viscosity

Key technical requirements

New Japanese and Korean models 0W-16/0W-20 require ILSAC GF-6A certification

German old turbine 0W-30/5W-30 HTHS ≥ 3.5mPa · s

Domestic small displacement 5W-30 ash content ≤ 0.8% (mandatory for National VI B)

3、 Strengthening plan for extremely cold regions (below -30 ℃)

Oil upgrade

Choose PAO+ester total synthesis (such as Mobil 1 0W-20)

Add liquid molybdenum disulfide (reduce cold start friction by 60%)

supporting measures

Replace AGM battery (CCA ≥ 700A)

Install oil pan heating belt (preheating to -10 ℃ only takes 15 minutes)

Emergency skills

Repeatedly open and close the key 3 times before starting (to allow the oil pump to pre establish pressure)

Wait for 2 minutes after the first ignition failure (to avoid battery depletion)

4、 Three major misconceptions about winter oil use

❌  Misconception 1: "High viscosity engine oil keeps you warmer"

→ Truth: 5W-40 has 4 times higher cold start wear than 0W-20 (FZG gear turbine test)

❌  Misconception 2: "It is necessary to warm up the car for 5 minutes in winter"

→ Truth: Modern engines only need to idle for 30 seconds and slow down for 1 kilometer (prolonged hot driving actually increases carbon deposits)

❌  Misconception 3: 'Southern regions do not require low-temperature engine oil'

→ Truth: Wuhan/Chengdu and other places often reach -5 ℃ in the early morning, and 10W engine oil is close to the freezing point

5、 Comparison of Practical Cases

Heilongjiang Heihe River (-35 ℃):

Using 10W-40: startup success rate of 38%, average time of 9.2 seconds

Switching to 0W-20: Start success rate of 91%, takes 2.8 seconds

Beijing (-15 ℃):

5W-30 saves 40% of startup power consumption compared to 10W-40 (extending battery life)

6、 Recommended Oil List for Winter 2024

Climate zone

Economic choice

High end selection

Severe cold zone (<-25 ℃) Shell Helix 0W-20 Mobil 1 ESP 0W-30

Cold Zone (-15 ℃) Jia Shi Duo Extreme Protection 5W-30 Total 9000 5W-30

Wet cold zone (>-10 ℃) Great Wall Jinji Star 5W-40 Kunlun KR9 5W-40

Ultimate suggestion:

Before entering winter, it is necessary to complete the oil grade upgrade and battery testing. These two costs are less than ¥ 500, but they can avoid trailer fees (¥ 300+/time) and engine overhaul risks caused by difficulty starting. Remember: Cold start wear with the wrong engine oil at -20 ℃ is equivalent to normal driving for 500 kilometers!