Converting A Toyota 3.0L To A 3.4L - Why And How

4Runner conversion

First of all, there’s nothing wrong with the standard Toyota 3.0L V6 engine. For those who only need to get from point A to point B and take their 4Runner off-road sparingly, the 3.0L will probably do just fine.

Then there are you off-road enthusiasts. You need more power, more reliability, and better overall performance. And we’re all for that. (Like you can see here.)

Once you get the swap, you’ll notice a discernible difference whether you’re climbing hills, 4-wheeling to a secret camping spot, or racing down the highway.

Why Switch Engines?

4Runner conversion lifted

A 4Runner mid-conversion via 

There are many reasons to perform this engine swap, but the main reasons have to do with performance and reliability (and whose not interested in that?):

  1. To start, the 3.4L engine features better technology than the 3.0 engine your 4Runner came with. Lightweight and powerful - with 190 HP (a 45 HP increase) - it’s equipped with a Toyota multi-port fuel injection system. The dual overhead camshaft design of the 3.4L lends itself to fuel efficiency and the opportunity for more power upgrades.
  2. Most people agree the 3.4L is a sturdier engine than the 3.0L and less likely to fail.
  3. Unlike a lot of engine swaps, a 4Runner with a 3.0L will readily accept a 3.4L. No frame alterations are required, there are no concerns about driveline durability after the swap, etc.

Basically, the 3.4L is better than the 3.0L, and the swap is about as straightforward as engine swaps get. So, why not?

The Swap

4Runner conversion engine

A fully converted engine via

While there are plenty of shops out there that would gladly perform this conversion, it’s not out of the question for you to do it yourself. In fact, it’s pretty straightforward.

4Runner conversion testing

Image via

Here’s what the swap requires:

  • Electrical work to combine the new engine management system with the factory vehicle wiring. This keeps all systems functioning properly.
  • Custom exhaust work so the new engine connects to the existing exhaust system
  • An OBDII compliant catalytic converter
  • A plan to relocate the battery

You'll also likely have to deal with hood clearance issues as the 3.4L engine sits higher and hits the hood when it’s closed. While some 4Runners have enough clearance, most will need a scoop or body lift to make it happen.

What you'll want:

  • A 'donor' 3.4L V6, which can be pulled at a junkyard or sourced from any number of websites
  • A swap kit, which can be had from,, and some other places

You can do a swap without a kit, but the kits are priced very reasonably and save a lot of time.

NOTE: Both and will sell a kit and a used engine as a complete package. Definitely consider this.

OEM Parts

Sometimes, when you start working on your vehicle, you get the bug to keep going. After you’ve swapped out your engine, be sure to visit our website for a wide selection of quality OEM parts, even for older 4Runners. And if you ever have any questions about engine swaps or anything else, feel free to give one of our experts a call.

Do you have experience with the 3.4L engine swap? Tell us about it on Facebook!