Mitsubishi GS16-GS25 engine oil & fluids
Mitsubishi GS16-GS25 engine oil & fluids
Which engine oil for your Mitsubishi GS16-GS25 and how much goes in? This page lists all oil types, viscosities and exact fill quantities for the engine, transmission, front axle and cooling system — exactly as specified in the original manual, for the GS16, GS18, GS20, GS21, GS23 and GS25.
Suitable for the entire series: Mitsubishi GS16, GS18, GS20, GS21, GS21S, GS23, GS25 and GS25S.
Mitsubishi GS16-GS25 engine oil
The S3L and S3L2 diesel engine requires a diesel engine oil of API class CD or higher, viscosity SAE 10W-30. The 10W-30 is an all-season choice; in consistently warm weather you can opt for a thicker oil (SAE 20W or 30), and in severe cold a thinner one. The capacity is the same across the entire series.
| Fluid | Type / class | Capacity |
|---|---|---|
| Engine oil | Diesel API CD+, SAE 10W-30 | 3.8 liters |
Always check the level before starting, on level ground, and top up to the upper mark on the dipstick. After a filter change, some extra oil goes into the filter, so check the level again afterwards and top up if necessary. The oil pan has two drain plugs.
Mitsubishi GS16-GS25 transmission and hydraulic oil
The transmission shares its oil with the hydraulic and wet-brake systems. Therefore use a gear/hydraulic oil API GL-4 or higher, SAE 80W, suitable for wet brakes. The capacity varies by model.
| Model | Type | Capacity |
|---|---|---|
| GS16, GS18, GS20, GS16-grade, GS21S | GL-4 SAE 80W (wet brake) | 18 liters |
| GS21, GS23, GS25, GS25S | GL-4 SAE 80W (wet brake) | 22 liters |
You drain the transmission oil via three drain plugs at the bottom of the rear part of the transmission housing. Note: with a front loader mounted, the oil level in the transmission drops — top up to the upper mark in that case. If you use a genuine Mitsubishi oil, Multi GB (SAE 80W, GL-4) is the right choice for this; Multi STOU (10W-30) is an all-in-one alternative that serves as both engine and transmission oil.
Mitsubishi GS16-GS25 front axle oil
The front axle (4WD) has its own gear oil: API GL-4, SAE 80W. Here too, the capacity varies by model.
| Model | Type | Capacity |
|---|---|---|
| GS16, GS18, GS20, GS16-grade, GS21S, GS25S | GL-4 SAE 80W | 4.0 liters |
| GS21, GS23, GS25 | GL-4 SAE 80W | 5.0 liters |
Change it for the first time after 100 hours, then every 200 hours. After topping up, open the bleed plugs on the left and right until oil flows out (about 20 seconds), and check the level with the dipstick plug.
Mitsubishi GS16-GS25 coolant
Use a long-life coolant (LLC) based on clean water — never muddy or salt water. From the factory, the system is protected down to -25 °C; after a year this protection decreases, so refresh it annually and mix based on the lowest expected temperature (for example, 40-45% concentrate for protection down to -25 °C).
| Model | Type | Capacity |
|---|---|---|
| GS16, GS18, GS20, GS16-grade | Long-life coolant | 4.0 liters |
| GS21, GS21S, GS23, GS25, GS25S | Long-life coolant | 4.2 liters |
Mitsubishi GS16-GS25 fuel
Regular diesel is used; the tank holds 23 liters. Choose the diesel type based on temperature: standard diesel down to about -10 °C, winter diesel down to about -20 °C, and special winter diesel below that. Always fill through the strainer and wipe away any spilled fuel immediately.
Product tip. If you're changing the engine oil, replace the engine oil filter (SKU-018) at the same time — it's part of every oil change. For a complete service with oil, fuel and air filter, the Filter set Mitsubishi GS series (SKU-100164) is the most economical option.
