FLUIDS Flashcards
(25 cards)
W meaning in engine oil
Winter
How the oil flows in cold temperatures
What does number indicates in engine oil
Lower number = thinner oil in cold, better cold starts.
So 5W flows better in cold than 10W.
5W-30
Good all-rounder for most modern engines. Great for cold starts.
10W-30
Slightly thicker, good for warmer climates.
15W-40
Often used in diesel engines or in hot climate
20W-50
Older engines or extreme heat. Very thick.
0W-20
Very thin, used in fuel-efficient or hybrid engines.
What is 40 in oil
40” = Viscosity at high temperatures
The 40 means the oil stays thicker and more stable when hot, giving strong protection under high heat and heavy loads.
Types of engine oil
- Conventional oil (mineral oil)
- Synthetic oil
- Semi synthetic (blend)
- High mileage oil
ATF stands for
Automatic Transmission Fluid (ATF):
ATF CHARACTERISTICS?
Usually red or pink
Thinner and made for automatic shifting (lubes,cools & powers)
Used in most modern vehicles
Common types: DEXRON, MERCON, or CVT fluid (for CVT transmissions)
MTF STANDS FOR
Manual Transmission Fluid:
Characteristics of MTF
Usually thicker (like gear oil)
Can be 75W-90, 80W-90, or similar
Not always red—often clear, amber, or dark
Some manuals even use ATF, so always check the vehicle manual
How to Check ATF
Most autos have a transmission dipstick (just like the engine oil one)
Check while the engine is warm and running, in Park or Neutral
Fluid should be clear and reddish—not dark or burnt
What is gear oil used in
Used in
-Manual transmission
- Differential
Gear oil characteristics
-thick oil
- only pure lubricantion
-no hydraulic functions
Dexron ATF
Dexron is a brand name for a series of automatic transmission fluids (ATF) created by General Motors (GM)
Mercon ATF
it’s Ford’s version — their own brand of automatic transmission fluid (ATF).
LV Meaning in fluid
Low viscosity
ULV meaning in fluid
Ultra low viscosity
75W-90
Gear oil made to lubricate differentials, manual transmissions, and transfer cases, especially in heavy-duty and performance applications.
80w-90 ??
Is a gear oil use in
Manual transmissions
Differentials
Transfer cases
Heavy-duty equipment (trucks, tractors, industrial machines)
Signs transmission fluid need changing
Slipping gears
Delayed shifting
Strange smells (burnt)
Dirty or dark fluid
Grinding or whining sounds
EP-90
gear oil that’s specifically designed for extreme pressure
