The Honda 350 quad (commonly the TRX350 Rancher family) typically uses 10W-40 four-stroke ATV/motorcycle engine oil, with a total capacity around 2.2–2.6 quarts when changing the oil and replacing the filter. Always verify the exact specification for your year and model in the owner's manual.
Because the 350 quad has multiple variants across years (such as TRX350FA and TRX350FE), the precise oil grade, viscosity, and capacity can vary. Use a reputable ATV or motorcycle oil that meets API and JASO specifications, and avoid car oils with friction modifiers that can affect the clutch and transmission. The following guidance covers common practices and how to confirm the right spec for your machine.
Oil type and viscosity
Before listing specifics, note that selecting the correct oil involves the right viscosity, API rating, and compatibility with the ATV’s transmission. The guidance below reflects widely used defaults for many Honda 350 quads.
Recommended oil grades
Before the list, this paragraph explains the purpose of the items that follow.
- Viscosity: SAE 10W-40 is commonly recommended for most 4-stroke Honda ATVs, including the 350 family, across a range of riding conditions.
- Specification: Use an API-rated four-stroke motorcycle/ATV oil that meets or exceeds API SL/SM/SN and, if possible, JASO MA or MA2 compatibility.
- Brand guidance: Honda GN4 10W-40 is a standard OEM-recommended option; any equivalent high-quality 10W-40 motorcycle/ATV oil that meets the API/JASO specs is acceptable.
- Important caveat: Do not use automotive engine oil with friction modifiers or additives not intended for motorcycle/ATV clutches and transmissions.
In summary, choose a 10W-40 oil formulated for motorcycles/ATVs, with appropriate API/JASO ratings; confirm compatibility for your specific model/year.
What to avoid
This paragraph introduces items to steer clear of when selecting oil.
- Avoid car oils that include friction modifiers not suitable for ATV clutches.
- Avoid oils not rated for four-stroke motorcycle/ATV use or lacking the correct API/JASO specifications.
- Avoid blends that Honda does not list for your year/model; when in doubt, stick to a trusted ATV/motorcycle oil (e.g., GN4 or equivalent).
Using the right oil specification helps protect the engine and transmission in a Honda 350 quad across its service life.
Capacity and service notes
To help you plan an oil change, consider the typical capacity ranges and the need to replace the filter during maintenance. Exact numbers depend on year and variant, so use your manual for confirmation.
Capacity by model/year (typical ranges)
Before the list, this paragraph clarifies why the numbers vary and what to expect.
- Engine oil capacity (including the filter): approximately 2.2–2.6 quarts (about 2.0–2.5 liters), depending on year and whether the filter is replaced during the change.
- Oil filter replacement: always replace the filter at oil changes when upgrading or maintaining the engine.
- Check level on level ground after warming the engine and turning off; fill to the Full mark per the manual’s guidance.
In short, plan for roughly 2.2–2.6 quarts with a new filter, but verify your exact figure from the owner’s manual or Honda’s service portal for your specific year and model.
How to verify the exact spec for your bike
Because Honda released multiple variants of the TRX350 over the years, the most reliable source is your vehicle’s owner’s manual or Honda’s official specifications. If you don’t have the manual, you can:
- Check Honda’s official support site by model year and VIN.
- Ask a local Honda dealer or a qualified ATV technician for the exact oil grade, capacity, and filter part numbers for your specific machine.
Following the official guidance ensures you use the correct oil and avoid potential issues with the engine and transmission.
Summary
For most Honda 350 quads, the standard recommendation is a high-quality 10W-40 four-stroke ATV/motorcycle oil, typically around 2.2–2.6 quarts including the filter. Always confirm the exact specification for your year and variant in the owner's manual or via Honda’s official service resources, and replace the oil filter at each oil change. This approach helps maintain reliable performance across the life of the vehicle.