For a 2018 Nissan Sentra equipped with a CVT, transmission fluid is added through a fill plug on the side of the CVT housing using Nissan CVT Fluid NS-2. The process is different from traditional automatic transmissions, and many owners find that service is best left to a professional if they’re not comfortable with under-car work.
Fluid type and compatibility
Use only Nissan CVT Fluid NS-2 for the Sentra’s continuously variable transmission. Do not mix NS-2 with other transmission fluids, and avoid using standard automatic transmission fluids. Using the wrong fluid or mixing fluids can cause CVT slipping, overheating, or damage over time.
- Nissan CVT Fluid NS-2 is specified for most 2018 Sentra CVTs. Check your owner’s manual or confirm with a Nissan dealer if your vehicle has any unusual equipment or market-specific variations.
- Never substitute Dexron/Mercon or other ATF fluids in a CVT unless explicitly approved by Nissan for your exact model and year.
- Store new NS-2 fluid in a clean container and avoid contamination from dirt or water during handling.
Keeping to the specified NS-2 fluid helps ensure smooth CVT operation and helps protect the transmission from wear and overheating.
Where to locate the fill point on a 2018 Sentra CVT
The fill location on the Sentra’s CVT is not part of the engine’s oil fill system. Instead, you’ll find a fill plug on the side of the CVT housing. Access typically requires lifting the vehicle and may involve removing a protective splash shield. Once you locate the side-fill plug, you can add NS-2 CVT fluid as needed, or confirm the fluid level when performing a level check.
- Prepare the vehicle: park on level ground, drive to circulate the transmission to operating temperature, and safely raise the front of the car with jack stands if necessary.
- Locate the CVT housing’s side where a square or hex-shaped fill plug resides; this is separate from the drain plug on the pan.
- Have the correct NS-2 fluid and a long funnel or applicator ready to add fluid through the fill hole if the level is low.
Because access to the fill plug can vary and the system is sealed, consult the service manual or a Nissan technician if you’re unsure about the exact location or process for your specific Sentra configuration.
Steps to check and top up CVT fluid
Below is a general guide to checking the level and topping up if needed. The procedure should be performed with the engine warm and the car level, and you may need an assistant to help with certain steps.
- With the engine warmed up (driven a short distance) and the car on level ground, safely raise the front of the vehicle and support it.
- Remove the side-fill plug on the CVT housing to check level. If fluid drips out of the fill hole, the level is adequate.
- If no fluid drips from the fill hole, slowly add NS-2 CVT fluid through the fill hole using a long funnel until it begins to dribble out slightly.
- Reinstall the fill plug securely and clean any spilled fluid.
- Recheck for leaks and ensure the transmission remains at a proper operating temperature before driving again.
Keep in mind that CVT servicing is sensitive: overfilling can cause foaming and poor performance, while underfilling can lead to slipping and overheating. If you’re unsure about the level or the correct steps for your vehicle, seek professional service.
DIY considerations and safety cautions
Work under a car carries risk, especially when dealing with the transmission. Always use proper lifting equipment and stands, wear eye protection and gloves, and avoid contact with hot surfaces. If you lack confidence or the vehicle is not easily accessible, a Nissan-certified technician can perform a CVT fluid check or replacement with the appropriate NS-2 fluid and the correct procedures.
When to seek professional service
CVT fluid changes, level checks, and fill procedures can be tricky on the Sentra. If you notice slipping, shuddering, reduced performance, or abnormal noises, or if the level check indicates an unusual reading, contact a qualified technician. A dealer or trusted shop can verify the fluid type, perform a proper level check, and carry out any needed service with the correct torque on plugs and the correct quantity of NS-2 CVT fluid.
Summary
In a 2018 Nissan Sentra, transmission fluid is added through a side fill plug on the CVT housing using Nissan CVT Fluid NS-2. Do not use standard ATF, and avoid filling through the engine oil system. The process often requires lifting the vehicle and may involve removing a splash shield for access. If you’re not comfortable performing the check or top-up yourself, have the service done by a Nissan technician to ensure proper fluid type, level, and transmission health.