Passenger vs. Driver Side: Which Oil Catch Can Does Your Mustang Actually Need?
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You just bought a 2015–2023 Mustang GT.
You go online to buy an Oil Separator (Catch Can) because the forums told you to.
But then you see options: Passenger Side, Driver Side, or Both.
You don't want to spend $400 if you don't have to. So, which one is actually doing the work?
The answer lies in the PCV (Positive Crankcase Ventilation) system.
On the Coyote 5.0L, the air circulates in a specific direction.
- Passenger Side: The "Dirty Side." This is where air exits the crankcase, carrying hot oil vapor with it towards the intake manifold. This side captures 95% of the oil.
- Driver Side: The "Clean Side." This is where fresh air enters the crankcase. Unless you are running high boost (Supercharger/Turbo), there is rarely any oil on this side.
In this guide, we show you what 3,000 miles of "blow-by" looks like in a J&L cup, and why simply buying the Passenger Side kit is the smartest $150 you can spend on your engine.
Compare Catch Can Options
OEM Style or Maximum Capacity?
|
Brand / Model |
Capacity |
Installation |
Best For |
|
J&L 3.0 (JLT) |
3.0 oz. |
Instant. (Plug-n-Play). |
The Standard. #1 Best Seller. Clear bottom option available. |
|
Ford Performance |
Small. |
Instant. (OEM Clips). |
OEM+ Builds. Looks like a factory part. 50-State Legal. |
|
Mishimoto Baffled |
Medium. |
Bolt-On. (Bracket). |
Heavy Duty. Bronze filter + baffling for track abuse. |
|
UPR Dual Valve |
Large. |
Complex. (Routing). |
Boosted Cars. The pro choice for 800HP+ builds. |
Frequently Asked Questions (Catch Cans)
Does a catch can add horsepower?
Technically, no. Ideally, yes.
A catch can doesn't create power. However, it prevents losing power.
When oil vapor enters the combustion chamber, it lowers the octane of your fuel (e.g., turning 93 octane into 89). This causes "knock," and the computer reacts by pulling timing (reducing power). By catching the oil, you keep your fuel pure and your timing advanced.
Why doesn't Ford install these from the factory?
Maintenance.
A catch can requires the owner to physically open the hood and empty it periodically. If a regular driver forgot to empty it, the can would overflow and suck a slug of oil into the engine, causing damage. Manufacturers route the vapor back into the engine to be burned off (emissions) to avoid this maintenance liability—even though it's worse for performance.
Will this void my warranty?
Unlikely.
Catch cans are generally considered preservation devices. Because they protect the engine from carbon buildup and sludge, most dealerships and service advisors view them positively. Parts like the Ford Performance separator maintain a factory appearance and are widely accepted.
Stop the sludge.
Keep your intake clean and your valves happy. Shop our verified collection of 2015–2023 Ford Mustang Oil Separators.