2012 Nissan Quest

Used‑Oil Analysis & Follow‑Up Plan

Lab sample dated July 12, 2025; AMSOIL Signature Series 5W‑30 and Ea15K12‑EA filter had 3000 miles and 32 months in service when tested. Based on this information, and since the Quest is not driven much, I would probably let the oil and filter change go for three years. It is not driven much since it has other issues like the AC compressor needs replaced along with the rest of the work that goes with that, engine mounts need replaced, front wheel bearings, CVT issues like slipping, stalling, and shuddering when accelerating from a stop.

I did regular CVT fluid changes with other NS-2 fluids with the oil changes. The CVT fluid was drained from the drain plug or siphoned out, then refilled from the dip stick tube and was level checked at the correct fluid temp range. I did not use AMSOIL 100% Synthetic CVT Fluid fluid until the oil change on 11/2022. The Quest was replaced right after that because of these issues. We have used it like a cargo van and for local driving since then. The engine has zero issues, everything else falls apart around it. 159,000 miles seems adequate for a NISSAN CVT with regular fluid changes. It most likely would have been longer if I was using AMSOIL CVT fluid the entire time. It was purchased in 2015 with 60,000 miles.

I recently changed the CVT fluid again with AMSOIL 100% Synthetic CVT Fluid on 06/2025 and it greatly improved the CVT slipping. Before this change I had to be very careful when accelerating from a stop to keep it from shuddering and stalling out. It was also not able to accelerate from an incline without first accelerating from a level road. After changing the fluid again you could accelerate almost normally with very slight shuddering and no stalling from an incline. I will change the CVT fluid change at the next oil change and see if there are any more improvements.

What I Did and Why it Matters

I installed AMSOIL Signature Series 5W‑30 (ASL) and an Ea®15K12‑EA filter at 159 000 miles in Nov 2022 (oil capacity 5 qt). Nissan lists a 7 500‑mile / 6‑month oil‑change interval for normal service on the Quest. Because I drive only ~1 500 miles per year, time—not mileage—forces my oil change. A used‑oil analysis lets me stretch drains safely and reduce waste.

Key Lab Numbers vs. Industry Guidelines

  • Iron — 12 ppm · Well under the ~100 ppm caution line; wear remains very low.

  • Fuel dilution — 1.0 % · Safely below the 2.4 % limit for gasoline engines.

  • Oxidation — 40 abs/cm · At the industry watch level (> 30 abs/cm) but not yet thickening the oil.

  • TBN (base reserve) — 4.5 mg KOH/g · Above the 3 mg change‑oil trigger; plenty of additive left.

  • Viscosity @ 100 °C — 10.5 cSt · Smack in the SAE 30 window (9.3 – 12.5 cSt); no shear or thickening.

  • Silicon — 17 ppm · Indicates good air filtration (< 20 ppm target).

  • Ea®15K12‑EA filter efficiency — 99 % @ 20 µm · Premium filtration keeps wear metals down.

Take‑away: Wear metals are low, viscosity is on‑grade, TBN is healthy and contaminants are minimal. Oxidation has reached the caution line but is not yet affecting viscosity. The lab rated the sample “NORMAL – oil suitable for continued use.”

How Long Can I Safely Run This Oil?

  1. Base Reserve Trend – Fresh Signature Series starts near 12 TBN ; at 4.5 after 32 months, linear projection reaches the 3 TBN limit in roughly 10 more months.

  2. Oxidation Ceiling – Industry warns of rapid viscosity rise above 30‑40 A/cm; I am at the upper edge now, so another ~2 000 miles (about one more driving season) is prudent.

  3. Filter Rating – The Ea15K12‑EA is designed for 15 000 miles or one year; it is time‑expired even though mileage is low.

My Plan:

  • Replace oil and filter at 5 000 total miles on the fill OR by November 2025, whichever comes first. This keeps TBN above 3, oxidation below critical levels.

What I Will Install Next

The same thing I use now.

Why AMSOIL Works for Low‑Mileage Drivers

  • Signature Series offers 28 % more acid‑neutralizing power than Mobil 1, giving extra capacity for long time‑based drains.

  • The oil’s 25 000‑mile / 1‑year guarantee ensures peace of mind even if my usage pattern changes.

  • Full‑synthetic base stocks resist fuel dilution and oxidation better than conventional oils, protecting the Quest’s 3.5 L VQ35DE in hot Tennessee summers.

Quick Reference

  • Vehicle: 2012 Nissan Quest, 162 000 mi

  • Sample date: 12‑Jul‑2025

  • Miles on oil: 3 000

  • Oil / Filter used: AMSOIL Signature Series 5W‑30 + Ea15K12‑EA

  • Next service: November 2025 or 5 000 mi on oil, whichever comes first