Know what is already being used
Check the cab, supply shelf and last driver's record. Note the exact product and package size. A seasonal change should begin with known information rather than layering a new bottle onto an unclear history.
Choose one operating plan
Decide whether the official guidance for separate products or a combined option better fits your routine. Count the measuring steps and consider who performs them. Write the selected instructions in one place.
Make the transition visible
Date the new instructions and remove superseded notes. Tell each driver when the plan changes. Recheck again if the vehicle moves to a different route, returns from storage or is assigned to a new operator.
Check the official directions
Use the current package label and manufacturer documents for treatment rates, handling and application details.
Independent dealer link. Current price and availability are shown by AMSOIL.
Practical checklist
- List existing products and the last treatment.
- Compare winter options using official guidance.
- Replace the old fill note and notify other drivers.
Questions before you buy
What is the first step before switching?
Identify what is currently being used and what has already been added.
Should I keep both old and new fill notes?
Keep a history if useful, but make only the current instruction active and obvious.
Related questions and products
- When to add winter treatment
- Combined treatment versus 4-IN-1
- When to add diesel anti-gel
- AMSOIL Diesel Cold Flow Fuel Additive
- AMSOIL Diesel 4-IN-1 Fuel Additive
Prepared by SyntheticOilHQ, independent AMSOIL dealer 313120. Product information checked October 16, 2026. Consult the current manufacturer label for application details.