5VZ-FE Swap

FAQ: 3.4L (5VZ-FE) Conversion

[toggler title=”Does it matter if the donor parts are all from the same vehicle?”]

Yes, we recommend that all donor 3.4L parts are from one vehicle. Toyota made many small changes from model to model and year to year. Matching an ECU, engine harness and related sensors from different vehicles is possible but can be a mess.[/toggler]

[toggler title=”What information do you need to place my 3.4L Kit or Harness order?”]

Donor (3.4L) vehicle: VIN#, Year & Model, 2/4WD, Auto/Manual Trans. If there is any uncertainty about this information, we’ll need to Toyota part #’s to verify, see below.

Recipient (your) vehicle: VIN#, Year & Model, 2/4WD, Auto/Manual Trans, IFS/SAS, Original Engine (what came stock in your truck), Rear-wheel ABS Y/N, and if you will be using stock exhaust manifolds or headers.

Pictures: Here are some applications that we have found to be inconsistent w/ published information. We will need the following pictures for the following applications:

  • -1989-1990 Recipient Vehicles:
    • There are 2 connectors in the passenger-side “kick-panel”, behind the OEM ECU. One is a white connector and the other is gray. We need a picture of the face of these connectors (opposite the wires).
  • -1999-2000 Tacoma Donor Vehicles:
    • There will be 2-4 connectors on the engine harness that connect to the 3.4L ECU, they will be toward the inside of the vehicle from the firewall grommet. We need a picture of the face (opposite the wires) of only one of these connectors to see what style is used.
    • On this model we also need a picture of the large harness-harness connector. This connector is on the engine harness near the ECU connectors. It will be larger than the ECU connectors. It will have a “knob” on each side of the housing. We need a picture of the face of this connector (opposite the wires).

See core information below.

Providing the correct information is the sole responsibility of the customer. ORS will not be responsible for correcting parts due to mis-information.[/toggler]

[toggler title=”Without a reliable VIN, how can I tell what year/model my 3.4L is?”]

On the harness there is a 10-digit part number that starts with “82121-_____”. This number is printed on a tag near the firewall grommet.

On the ECU there is a number that starts with either “89661-_____” or “89666-_____”.

Your Toyota dealer can identify the model and year using these part numbers. In this case ORS will request these part numbers when placing your order.[/toggler]

[toggler title=”Do I need to send in core connectors/harnesses to have an ORS harness built?”]

Most orders do not require core connectors and most harness are built from all-new parts. However, some connectors have become obsolete and cores are required. The following are applications where core connectors are needed:

  • 1985-1990 22R-E and 3VZ-FE Recipient Vehicles
    • The cores needed are the harness-harness connectors (2) that connect the original engine harness to the OEM main or “dash” harness. These connectors are located in the passenger-side “kick-panel” area, behind the OEM ECU. These will be yellow, gray or white depending on the year. We only need the connector housings on the ENGINE HARNESS side of this connection.


[toggler title=”What parts are needed to complete this swap?”]

Donor Parts

Conversion Parts


[toggler title=”What automatic transmission can I use? Will my 3.0L auto transmission work with the 3.4L engine and computer?”]

You can use an A340 automatic transmission from a 3.4L or 3.0L application. ORS recommends the 3.4L version for a couple of reasons:

  • If the donor engine is from a Tacoma, 4Runner or Tundra the 3.0L version will not work flawlessly. The engine computer also operates the automatic transmission. There is a different type of output shaft speed sensor in the newer (3.4L version) transmissions that the ECU will be looking for. Unfortunately the 3.0L sensor is also not easily interchangeable with a newer type. This will create an imperfect shift pattern and a constant engine trouble code (check engine light).
  • T100 donor engines don’t share this problem. If you plan to use the 3.0L transmission a T100 donor engine will work well and is highly recommended.
  • Keep in mind that the 3.4L version of the A340 auto transmission was upgraded in performance and strength from the 3.0L version and may be worth the additional cost, see below.
  • In a 2WD applications transfer case issues don’t apply and a 3.4L version of the auto transmission is highly recommended.


[toggler title=”Will my transfer case work with a 3.4L version automatic or manual transmission?”]

No, and neither will the 3.4L transfer case.* You will need a gear-driven transfer case from a 1979-1995, 4-cylinder, manual transmission Truck or 1984-1993, 4-cylinder, manual transmission 4Runner. The transfer case must to be converted to or equipped with a 23-spline input shaft and top-shifting configuration. You will also need a Marlin Crawler transmission x transfer case adapter (available from ORS) for installation of this transfer case. Some of our A/T conversion kits are equipped with this adapter.

This transfer case is needed to correct the front driveshaft output. On Tacomas, 4Runners, and Tundras the front driveshaft output is on the driver side. On your vehicle it outputs on the passenger side.

*Unless you have a T-100 donor vehicle. If the donor 3.4L parts and transmission are from a T-100, the T100 front driveshaft output is on the passenger side (like yours). In this case the T100 transmission and transfer case would work without modification.

An Atlas transfer case can also be used behind some 3.4L transmissions. Advanced Adapters manufactures an adapter to make this happen. This would be ideal for hard-core applications that may require the additional strength.[/toggler]

[toggler title=”What manual transmissions can I use?”]

You can use an R150 (found behind the 3.0L & 3.4L) or an R151 (22R-TE turbo applications) transmission. If the R150 is from a 3.0L it is a direct bolt-in to the 3.4L engine and also to the 3.0L chassis.

If you have an ‘84-‘95 4-cylinder chassis you can use this transmission with its original cross-member and drive-shafts (same wheelbase) to make this portion a “bolt-in”. From there, the ORS motor mounts can be used to mount the engine easily.

If the R150 is from a 3.4L you will need to refer to the transfer-case issues above if your vehicle is a 4WD. Also note that the 3.4L version of the R150 will not work with the ORS Exhaust Crossover Pipe.

The 3.0L and 3.4L version of the R150 have different input shaft lengths and must be used with their original bell-housings.

If you use an R151, you will need to use a bell-housing from a 3.0L.[/toggler]

[toggler title=”What clutch should I use?”]

If using 3.0L version of the R150 or the R151, we recommend the use of a 3.4L flywheel, clutch cover, clutch disc, and pilot bearing. With that, a 3.0L release bearing will be required.

Using all the 3.0L flywheel and clutch components is possible, but the 3.4L flywheel/clutch was upgraded in diameter for the increased power and should be used.

If using the 3.4L version of the R150, you will need the flywheel and all clutch components from a 3.4L application.[/toggler]

[toggler title=”What radiator should I use?”]

We’ve found that 90-95 3.0L radiators work the best with Trucks and 4Runners in this swap. We’ve found this radiator to work well, even in the Arizona summer with the A/C on. This radiator is also a direct bolt-in to most Trucks/4Runners.

If using this radiator we also recommend the use of the 3.0L fan shroud.[/toggler]

[toggler title=”What is the average install time?”]

Install times will vary greatly depending on the amount of detail put into the install. Well-executed swaps normally take 50-100 hours depending on the transmission setup, exhaust, accessories, installer’s learning curve, and the recipient vehicle.[/toggler]

[toggler title=”What would it cost to have ORS perform the swap for me?”]

Prices may differ depending on your individual swap. Please contact us to learn more.[/toggler]

[toggler title=”Do I need the dipstick drill guide?”]

Only 2000 and newer 3.4L models require drilling. 1999 and older models already have the necessary hole in the block.[/toggler]

[toggler title=”What are your crossovers made of?”]

They are made from mild steel. We recommend a ceramic coat finish before installing the ORS crossover.[/toggler]

[toggler title=”Can you install the crossover with the motor in the vehicle?”]

You can, however it is much more difficult this way. At a minimum you will have to remove the transmission crossmember and drop the transmission a ways to get the crossover pipe in or out of the vehicle.[/toggler]

[toggler title=”What do you recommend using for the exhaust?”]

There is no easy solution for the exhaust system, it must be custom-built; whether you use a crossover pipe or headers. We recommend using at least 2.5″ diameter exhaust tubing and components for best performance. We also recommend using a flex pipe in your exhaust system after the headers or crossover to prevent premature failure of these components. MORE INFO HERE.[/toggler]

[toggler title=”What should I do for my emissions?”]

If you have emissions testing where you live, check your local laws first. There is normally a legal way to do a swap.

This will involve some paperwork. Be sure to keep all information you have about the donor vehicle, especially the VIN.

Normally you will be required to use the emissions systems from the donor vehicle. This is possible with the ORS harness and the 3.4L emissions components.

NOTE: ’02 and newer 3.4L vehicles have a more complicated EVAP system. It is possible to work with this system, but in strict emission-law areas it can be difficult to use.[/toggler]

[toggler title=”Can my vehicle be switched from an A/T to a M/T during the swap?”]

Yes, this is actually done pretty often. First of all, you will need to notify ORS of the transition when ordering a kit/harness. We will change the parts accordingly.

You will also need to install a clutch pedal, bracket, and hydraulic system into your vehicle. We suggest using these parts from a M/T donor vehicle of the same model/year, this will make the swap relatively simple. The floor will also have to be modified to accept the new shifter locations.

If a “Clutch Start Cancel” switch is desired this will have to be hard wired into your vehicle’s start circuit.[/toggler]

[toggler title=”Can my vehicle be switched from a M/T to an A/T during the swap?”]

Yes, this is actually done pretty often. First of all, you will need to notify ORS of the transition when ordering a kit/harness. We will change your parts accordingly and add the necessary circuits to your wiring harness.

You will also need to modify your floor to fit the new A/T shifter. You may also want to change your pedal and bracket assembly to match that of an A/T vehicle.

The clutch start cancel switch will have to be bypassed in order for the start circuit to work.[/toggler]

[toggler title=”Will my stock EFI fuel pump work with this swap?”]

Normally the OEM 22R-E or 3VZ-FE fuel pump is sufficient for the 3.4L. If the 3.4L is supercharged, however, we recommend an upgraded fuel pump. We recommend an upgraded pump from URD, www.urdusa.com. If the upgraded pump is outside your budget you can normally retro-fit a 3.4L OEM pump into your stock pump location.[/toggler]

[toggler title=”How many oxygen sensors will I need to install with this swap?”]

You will need 2 oxygen sensors. All 3.4L engines use the OBD2 emissions standards. These standards require the use of 2 oxygen sensors. One sensor is installed before the catalytic converter and one is installed after the catalytic converter. This setup allows the ECU to monitor the efficiency of the catalytic converter(s). For this reason you will also have to install one or 2 functioning catalytic converters.

If the oxygen sensors or catalytic converter(s) are not functioning properly the ECU will detect this condition and the engine will run poorly.

*See the tech article for more info on oxygen sensor types and exhaust setup.[/toggler]