MagnaFlow 15145 MF Series Performance Cat-Back Exhaust System
Step by Step Installation and Instructions of the MagnaFlow 15145 Cat-Back Exhaust System.
This install is on a 2014; however, this exhaust will fit on other models. This is a very simple install and can take under 3 hours if you have two guys.
You will get the most out of this exhaust system if you install a cold air intake (CAI).
The CAI combined with an aftermarket exhaust will open up the airflow through your engine, thus increasing the overall performance. While you are at it, just install the entire list of performance mods for the 4Runner.
- System for 5th Gen 4Runner: Check Today’s Price
- TIP FINISH: POLISHED
- MATERIAL: STAINLESS STEEL
- 14mm Sockets
- 15mm Sockets
- Flathead Screwdriver
- Truck Creeper
- Jack Stands
- OEM Spare Tire Tools
- MagnaFlow_Instruction_Manual_5th_Gen_4Runner (PDF)
- Warning (PDF)
Step 1: Jack up Truck
You will want some car creepers or something to move around on once you are underneath the truck. This makes for an easy process for getting in and out from underneath your 4Runner.
Step 2: Unbolt Exhaust from Y-pipe
Start by unbolting the OEM 4Runner exhaust from the Y-pipe under the center of the truck. This is the piece that connects the actual muffler to the Y-pipe. At this point, you do not want to actually remove the exhaust or even the bolts. Leave the bolts connected. Right now we are just loosening the connection from the exhaust to the Y-Pipe. We don’t want to remove the bolts because we will need to remove two more bolts that are connected to the exit tubing.
In V6 and V8 engines where there is more than one exhaust bank, ‘Y-pipes’ and ‘X-pipes’ work on the same principle of using the low pressure component of an exhaust pulse to increase the velocity of the next exhaust pulse
Step 3: Unbolt Exhaust from Exit Tubing
We will need to remove two more bolts that are connected to the exit tubing. At this point, you want to loosen these bolts as well. It is important to keep the bolts on that are connected to the Y-Pipe as the whole system moves when you are trying to unbolt the exhaust from the exit pipe.
You remove the bolts from the Y-Pipe (like we did), you are going to have a hard time getting leverage on unbolting the exhaust from the exit pipe. We had to put the bolts back on to get enough leverage to remove the second set of bolts pictured below.
After you have loosened the 4 bolts from the Y-Pipe and the exit pipe, you can now remove all 4 bolts and set the aside.
Save the bolts from the Y-Pipe section, you will need these to install the new MagnaFlow Cat-Back Exhaust on your 4Runner.
Step 4: Use WD40 to loosen up the Rubber Connectors (Rubber Isolators)
Next, you want to remove all 5 of the rubber connectors (rubber isolators) that hold your exhaust on and prevent your whole truck from shaking when your engine is running. Pictured below are all 5 rubber connection points.
VERY IMPORTANT: Do not damage the rubber connectors, you will need these to install the new MagnaFlow Cat-Back Exhaust on your 4Runner.
To loosen the rubber connectors, use WD40 and a very small flathead screwdriver. Use the flathead screwdriver to open up the rubber connectors in between the rubber and metal. Spray the WD40 in between these small spaces and slide the rubber connectors back and forth until everything is sliding around nice and free.
VERY IMPORTANT: Do not remove any isolators at this point.
Rubber Isolator 1
Rubber Isolator 2
Rubber Isolator 3
Rubber Isolator 4
Rubber Isolator 5
Step 5: Remove OEM Exhaust
After you have greased up the rubber isolators with WD40, you can now remove all rubber connectors and remove the OEM 4Runner exhaust.
Step 6: Remove OEM Pipe
VERY IMPORTANT: Note that you will have to lower the replacement tire in the rear of the 4Runner to allow the old OEM exhaust pipe to exit and be removed. If you do not lower the tire, you will not be able to remove the exhaust pipe (yes, this happened to us as well). Hopefully, this helps you expedite the process a little faster.
Step 7: Ready for Install
Step 8: Feeding Tail Pipe
The first section of the new exhaust you want to install is this crooked looking piece of exhaust tubing, the tail pipe. This will go straight up and over the frame.
Step 9: Installing the Muffler
Once you have the exhaust back onto the rubber connectors, you can grab the two bolts that you disconnected from the Y-Pipe and bolt those back onto the new system.
Step 10: Installing New Tail Pipe (New Clamps)
Once you have the new exhaust bolted onto the Y-pipe and connected to all the rubber isolators, you can now start to clamp on the remaining two clamps in the rear and exit of the system.
That’s it! This is a very easy install if you have a couple spare hours in your day. It took us around 3 hours from opening the doors to having the new exhaust on.
You want to check out the exhaust in a couple days and make sure all of the rubber isolators are still in place.