If you're rolling up on six figures on your 3rd Gen Tacoma's odometer, there's a critical maintenance milestone you can't afford to overlook: the 100,000-mile coolant service. As shown in the video thumbnail above, this hands-on walkthrough covers exactly what it takes to properly drain and refill your Tacoma's cooling system using Toyota Super Long Life Coolant — a task every Tacoma owner should understand, whether you're daily driving your truck or prepping it for the next overland adventure.
In this guide, we're breaking down a real-world 100K mile coolant service performed on a 2018 Toyota Tacoma TRD Sport, walking through the entire process from prep to final inspection.
Why the 100,000-Mile Coolant Service Matters
Your Tacoma's cooling system is the unsung hero keeping your engine running at optimal temperatures, whether you're crawling over rocks on a technical trail or cruising down the interstate with a fully loaded overland rig. Toyota's factory coolant is engineered to last, but it doesn't last forever. By the time you hit 100,000 miles, that Super Long Life Coolant has been through years of thermal cycling, and its corrosion-inhibiting additives begin to break down.
Skipping this service isn't just a minor oversight — degraded coolant can lead to:
- Reduced corrosion protection for your radiator, water pump, and engine block
- Decreased heat transfer efficiency, especially critical during heavy towing or off-road use
- Potential scale buildup that restricts coolant flow
- Long-term damage to expensive engine components
For Tacoma owners who push their trucks hard on the trail, maintaining a healthy cooling system isn't optional — it's essential insurance for your investment.
What's Covered in This 3rd Gen Tacoma Coolant Service
This DIY guide applies directly to 2016–2023 3rd Gen Toyota Tacomas and walks through a complete drain and fill process (not a machine-powered flush). Here's the breakdown of what's covered:
Coolant Service Plan & Prep
Before diving in, the video outlines a full 100K-mile maintenance plan specific to the Tacoma platform, helping you understand where the coolant service fits into your broader maintenance schedule.
Toyota Super Long Life Coolant
Using OEM Toyota Super Long Life Coolant ensures you're maintaining the correct chemical compatibility with your factory cooling system. This isn't the place to cut corners with generic, off-the-shelf coolant — the video explains why sticking with Toyota's specific formulation matters.
Removing Radiator & Reservoir Caps
Step one is properly accessing the system by removing both the radiator cap and the overflow reservoir cap — a simple step, but one that requires attention to a hot engine and pressurized system safety.
Draining the Radiator
The video shows exactly where the drain point is located on the 3rd Gen Tacoma radiator and how to fully evacuate the old, degraded coolant from the system.
Refilling the Cooling System
Once drained, the process of refilling with fresh Toyota Super Long Life Coolant is demonstrated in detail, including proper mixing ratios and fill techniques.
Bleeding Air From the System
One of the most critical — and often overlooked — steps in any coolant service is working trapped air out of the system. Air pockets can cause overheating and inaccurate temperature readings, so this step gets dedicated attention in the walkthrough.
Final Level Check & Recap
After the refill, checking coolant levels and properly recapping the system ensures everything is buttoned up and ready for the road — or the trail.
Reference Material: Factory Repair Manual
For this service, the factory repair manual was used as a reference to ensure every step followed Toyota's official specifications. If you're planning to tackle this maintenance yourself, having access to the factory manual for your specific Tacoma model year is invaluable for torque specs, capacities, and system-specific procedures.
Tools Used for This Coolant Service
Having the right tools makes any DIY Tacoma maintenance job smoother. Here's what was used during this coolant service:
- Electric Ratchet – speeds up fastener removal significantly
- Ratchet and Socket Set – essential for accessing components around the radiator
- Trim Removal Tool Set – helps avoid damage to plastic clips and panels
- Torque Wrench – ensures proper reassembly torque specs are met
- 3/8 Ratchet and Socket Set – for finer work in tighter spaces
- Swivel Combination Wrenches – useful for awkward angles around the engine bay
Why This Matters for Overlanding Tacoma Owners
If you're running your Tacoma as an overland rig, you're likely putting it through more thermal stress than the average commuter truck. Steep grades, low-range crawling, sustained high RPMs on technical terrain, and remote locations far from a service shop all make a properly maintained cooling system non-negotiable. A coolant failure hundreds of miles from cell service isn't just inconvenient — it can strand you.
Staying ahead of scheduled maintenance like this 100K-mile coolant service is one of the simplest ways to keep your rig trail-ready and reliable, no matter how far off the beaten path you go.
Join the Tacoma Community
Tackling maintenance like this is always easier with a community behind you. Connect with other 3rd Gen Tacoma owners, share build tips, and get answers to your maintenance questions:
- TacomaPlanet Community: https://tacomaplanet.com
- Tacoma Store (parts and gear): https://tacomastore.com
- Smoky Mtn Taco: https://smokymtntaco.com
Final Thoughts
A 100,000-mile coolant service is one of those maintenance items that's easy to push off — until it isn't. Whether you're keeping your daily driver running strong or maintaining an overland-ready Tacoma for remote adventures, staying on top of your cooling system health protects your engine and your peace of mind. This drain and fill process is straightforward enough for most DIY-inclined owners to tackle in an afternoon with basic tools and the right coolant.
For the full step-by-step walkthrough, including exact drain point locations and air-bleeding techniques, check out the complete video below.
