---
id: guide-0014
title: "What fluids and filters does my vehicle need, and when should they be changed?"
category: guide
subtopic: maintenance-fluids
page_type: guide
source_url: "https://www.castlekiamchenry.com"
tags: ["maintenance", "fluids", "filters", "guide"]
questions:
  - "When do I change my oil?"
  - "What about coolant, transmission fluid, and air filters?"
  - "How often should filters be replaced?"
  - "What's the difference between synthetic and conventional oil?"
related: [maintenance-schedule, winter-prep, summer-prep]
dealer: Castle Kia McHenry
---

Your vehicle relies on several fluids and filters to run smoothly. Here's the breakdown:

**Engine oil & filter:** Typically every 5,000-10,000 miles (check your owner's manual). Synthetic oil lasts longer than conventional, so intervals may be wider. Regular changes keep your engine clean and protected.

**Air filter:** Usually every 12,000-15,000 miles or when visibly dirty. A clogged filter reduces fuel efficiency and engine performance.

**Cabin air filter:** Every 12,000-15,000 miles. Keeps your interior air clean and your AC working well.

**Coolant, transmission fluid, brake fluid:** These have longer intervals (often 30,000+ miles) but are just as vital. Low or dirty fluid compromises cooling, shifting, and braking.

**Why it matters:** Fresh fluids and filters prevent engine sludge, overheating, transmission problems, and brake failure. They're inexpensive insurance against major repairs.

Not sure what your vehicle needs? **Contact our Service department at (815) 453-8566** for a personalized fluid and filter check. We'll keep everything topped up and clean.