If you own a Subaru BRZ tS or its Toyota GR86 twin, you are driving one of the most engaging and pure sports cars on the road. But beneath that low slung, agile chassis lies a critical vulnerability that can turn a day of fun into a catastrophic engine failure. The factory plastic undertray, designed for aerodynamics and basic debris deflection, is a known weak point. This guide dives deep into why upgrading to a dedicated BRZ tS skid plate made of aluminum is not just a modification, it is an essential insurance policy for your engine.
Table of Contents
| Feature | OEM Plastic Undertray | Aftermarket Aluminum Skid Plate |
|---|---|---|
| Primary Material | Flimsy Plastic | 3/16" or 1/4" 5052 Aluminum |
| Primary Purpose | Aero, Minor Debris | oil pan protection BRZ & Impact Resistance |
| Impact Resistance | Low (Cracks Easily) | Very High |
| Weight | ~5 lbs | ~15 20 lbs |
| Long Term Cost | High (Replacement Parts) | One Time Investment |
The Flimsy Factory Undertray: A Design Compromise
Let us be clear. The stock BRZ tS front undershroud is not a skid plate. It is a large, flexible piece of molded plastic. Its job from the factory is to manage airflow under the car for cooling and stability, and to keep small road spray and pebbles away from sensitive components. It was never engineered to withstand a direct impact with a curb, a steep driveway transition, or an autocross cone.
I learned this lesson the hard way. After lowering my own BRZ tS on a set of quality coilovers, I heard that dreaded scrape on a seemingly mild incline. A quick inspection revealed a cracked and sagging undertray. The real horror came when I removed it. The oil pan, made of relatively soft aluminum, was sitting less than an inch from the point of impact. A slightly harder hit, or a differently shaped object, and I would have been looking at a punctured oil pan and a seized FA24 engine. The repair bill for that scenario starts at several thousand dollars.
This is a universal problem across the entire BRZ and GR86 platform. The oil pan is the lowest point on the engine, and it is dangerously exposed. Forums and social media groups are filled with stories of owners who have experienced everything from cracked plastic trays to fully breached oil pans. This is not a matter of if, but when, for any owner who drives their car with spirit or on anything less than perfect pavement.
What the Stock Piece Gets Wrong
- Material Failure: Plastic becomes brittle with age and heat cycles, shattering on impact instead of deflecting it.
- Poor Mounting: It is often secured with weak plastic push clips and small screws that shear off easily.
- Lack of Coverage: It offers no structural defense for the oil pan, leaving it completely vulnerable to direct hits.
The Aftermarket Savior: Engineered Aluminum Skid Plates
The solution is a purpose built aftermarket BRZ undertray constructed from aircraft grade aluminum. These are not mere replacements, they are significant upgrades designed specifically to address the OEM part's failures.
A high quality BRZ aluminum oil pan guard is typically fabricated from 3/16 inch or 1/4 inch thick 5052 or 6061 aluminum. This material is chosen for its excellent strength to weight ratio and its ability to absorb and distribute impact energy. Instead of cracking, it will dent, saving your oil pan from taking the full force of an impact.
Key Features of a Quality Skid Plate
- Robust Material: 3/16" or 1/4" 5052 Aluminum is the industry standard for a best skid plate for BRZ.
- Strategic Design: Features engineered bends and ribs for added stiffness and impact resistance.
- Comprehensive Protection: Covers the oil pan, oil filter, and often extends to provide differential cooler protection.
- Proper Mounting: Uses reinforced mounting points and high strength hardware to bolt directly to the chassis subframe.
- Serviceability: Includes access holes or dedicated doors for easy oil changes without removing the entire plate.
Why Every BRZ and GR86 Owner Needs This Upgrade
You might be thinking, "I drive carefully, I do not need this." But the need for a BRZ under body protection upgrade extends far beyond just aggressive driving.
| Driver Profile | Risk Factor | How a Skid Plate Helps |
|---|---|---|
| Lowered Car Owners | High. Reduced ground clearance makes impacts with driveways and road imperfections inevitable. | Acts as a sacrificial shield, preventing costly damage to the oil pan and engine. |
| Track Day & Autocross Participants | Very High. Curbs, off track excursions, and aggressive maneuvers pose a direct threat. | Essential BRZ track day mods for safety and reliability, protecting against session ending damage. |
| Daily Drivers on Rough Roads | Moderate to High. Potholes, road debris, and broken pavement are unpredictable. | Deflects rocks and debris, preventing surprise failures during your commute. |
| All Enthusiasts | Moderate. The OEM part is fragile and will eventually fail from fatigue or a minor scrape. | A one time upgrade that adds durability and preserves the value of your car. |
The question is not if you need a GR86 skid plate, but when you will install one. It is one of the most cost effective and critical reliability modifications you can make.
DIY Installation: A Step by Step Guide to Installing Your BRZ tS under tray skid plate
One of the best aspects of this upgrade is its DIY friendliness. You do not need a professional mechanic to get it done. With basic tools and a couple of hours, you can significantly increase your car's resilience.
Tools and Materials You Will Need
- New BRZ aluminum oil pan guard
- Floor Jack and Jack Stands (x4 for safety) or Vehicle Ramps
- Socket Set (10mm, 12mm, 14mm are most common)
- Screwdrivers (Flathead/Phillips)
- Torque Wrench (Recommended)
- Safety Glasses and Gloves
Can I use a jack and jack stands to install a skid plate? Absolutely. This is the preferred method for most DIYers. Ensure the car is on a level surface and that the jack stands are securely positioned on the chassis pinch welds or designated lift points. Never work under a car supported only by a jack.
The Installation Process
Step 1: Safety First and Car Preparation
Park on a flat, solid surface. Engage the parking brake and chock the rear wheels. Lift the front of the car using your floor jack and secure it on four jack stands for maximum stability. This gives you ample room to work.
Step 2: Remove the Old OEM Undertray
The stock undertray is held on by a combination of Phillips head screws and plastic push clips. Some may be corroded or tight. Use a well fitting screwdriver and a bit of patience. You may need to pry out the plastic clips carefully. As you remove the last screw, support the tray so it does not fall on you.
Step 3: Inspect and Clean
With the tray off, take a moment to inspect the oil pan and surrounding area for any pre existing damage or leaks. This is also a good time to clean the mating surface on the subframe.
Step 4: Test Fit the New Skid Plate
Carefully offer up the new aluminum skid plate to the chassis. Do not bolt it in yet. Ensure all the mounting holes line up and that it clears all components, including the headers and steering rack. Some minor filing of holes might be necessary depending on the manufacturer.
Step 5: Final Installation
Once you are satisfied with the fit, use the provided high grade hardware to bolt the plate into place. Start by threading all bolts hand tight to ensure proper alignment. Then, using your socket set and torque wrench, tighten the bolts to the manufacturer's specified torque value. Do not over tighten, as this can strip the threads in the chassis.
Step 6: Final Check
Give the installed plate a firm shake to ensure there are no loose connections. Do a visual check to confirm it is sitting flush and secure.
And that is it. You have successfully installed your first major piece of BRZ under body protection. The whole process is straightforward and immensely satisfying.
Frequently Asked Questions (FAQ)
Why does the BRZ/GR86 need a skid plate?
The factory plastic undertray provides zero impact protection for the oil pan, which is the lowest and most vulnerable part of the engine. A dedicated skid plate is necessary to prevent a punctured oil pan, which can lead to immediate engine failure and a repair bill in the thousands.
What is the difference between the stock BRZ undertray and an aftermarket skid plate?
The stock piece is a thin plastic shroud for aerodynamics. An aftermarket BRZ undertray is a structural component made of thick aluminum, designed specifically to absorb and deflect impacts that would otherwise damage the oil pan and other critical components.
How do you install a BRZ tS skid plate?
The installation process for an install BRZ skid plate is straightforward. It involves safely lifting the car, removing the old plastic undertray, test fitting the new aluminum plate, and securing it with the provided hardware. Basic hand tools and about 1 2 hours are typically required.
Is a skid plate necessary for a lowered BRZ?
Yes, it is absolutely necessary. Lowering the car reduces ground clearance, making contact with driveways, speed bumps, and road imperfections much more common and dangerous. A skid plate is the most important mod for any lowered BRZ or GR86.
Does a skid plate affect ground clearance on a BRZ?
Minimally. A well designed skid plate is only slightly thicker than the stock undertray, typically resulting in a loss of less than 1/4 inch of ground clearance. The protection it offers far outweighs this negligible change.
What material is best for a BRZ skid plate? (Aluminum vs. Steel)
Aluminum is generally the best choice. It offers an excellent balance of strength and weight. A BRZ aluminum oil pan guard is significantly lighter than a steel equivalent (15 20 lbs vs 40+ lbs) while providing more than enough protection for impacts with curbs and road debris. Steel is overkill for most applications and adds unnecessary weight.
Will a skid plate cause my engine to overheat?
A properly designed skid plate will not cause overheating. Many aftermarket plates are engineered with ventilation channels or holes to promote airflow. In some cases, they can even improve airflow management compared to a damaged or missing stock undertray.
Does the BRZ tS skid plate protect the oil pan and differential?
Yes, a high quality BRZ tS skid plate is designed to protect both the oil pan and often includes coverage for the differential cooler, providing comprehensive oil pan protection BRZ and differential cooler protection.
Where can I buy a BRZ tS under tray skid plate?
You can purchase quality skid plates from specialized automotive retailers, directly from manufacturers, or through online marketplaces that specialize in performance parts for Subaru and Toyota vehicles.
How much does a quality BRZ aluminum skid plate cost?
A high quality, USA made BRZ aluminum oil pan guard typically ranges from $250 to $400. This is a one time investment that can save you from an engine replacement costing well over $5,000.
Do I need any special tools to install a BRZ skid plate?
No special tools are typically required for an install BRZ skid plate. Basic hand tools like a socket set, screwdrivers, a floor jack, and jack stands are all you need to complete the installation successfully.
Can I use a jack and jack stands to install a skid plate?
Yes, using a floor jack and jack stands is the preferred method for most DIY installations. Always ensure the vehicle is securely supported on all four jack stands before working underneath it.
Are there skid plates that work with an aftermarket front lip or bumper?
Most universal skid plates are designed to work with the stock bumper. However, some manufacturers offer models or adapter kits for popular aftermarket front lips. It is crucial to check compatibility before purchasing if you have non OEM bodywork.
What are the best brands for BRZ/GR86 skid plates?
While several brands produce quality skid plates, look for manufacturers specializing in BRZ under body protection with a reputation for using high grade aluminum, precise fitment, and robust mounting systems.
How much weight does an aluminum skid plate add?
A typical BRZ aluminum oil pan guard adds between 15 and 20 pounds, which is a minimal weight penalty for the significant protection it provides to critical engine components.
Final Thoughts: Protect Your Investment
Your BRZ tS is a precision instrument, a car built for driving pleasure. Do not let a poorly designed piece of plastic be the reason that pleasure turns into a financial nightmare. Upgrading to a robust BRZ tS under tray skid plate is one of the smartest, most practical modifications you can make. It is a testament to the saying, "buy once, cry once." The one time cost of a quality aluminum guard pales in comparison to the alternative.
This upgrade is about more than just metal, it is about peace of mind. It is the confidence to tackle a backroad without flinching at every dip, to push a little harder on track day, and to navigate a steep driveway without that sinking feeling in your stomach. For the BRZ tS skid plate is not an accessory, it is an essential component for any enthusiast who truly uses their car as intended.
Ready to Secure Your BRZ or GR86?
Stop risking your engine. Browse our selection of high quality, direct fit aluminum skid plates designed specifically for the Subaru BRZ tS and Toyota GR86. Protect your drive today.
Disclaimer: This article is for informational purposes only. The installation of aftermarket parts should be performed by a qualified individual. Always follow the manufacturer's instructions and use appropriate safety equipment. The author and publisher are not responsible for any damage or injury resulting from the use or misuse of this information.
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