3.4L ENGINE CONVERSION TECH INFO - AUTOMATIC TRANSMISSION

Intro

Here at Off Road Solutions we are proud to be a part of the 3.4L engine conversion craze. We offer conversion kits designed to allow the easy installation of a Toyota 3.4L engine into an older Toyota Truck or 4Runner. We also manufacture parts that can be used to put this engine into virtually anything. Our parts are derived from many knuckle busting years of performing this conversion. Here is some information that should be helpful when considering (and performing) this conversion.

Before reading too far, we want to be honest. No matter how you look at it, engine conversions can be very costly and time consuming. This conversion is great for those wanting something different, those who love their older Toyota, and those in search of "sweetness." Another factor to keep in mind is that this swap is considerably more expensive with an automatic transmission compared to with a manual transmission. As you will read later in the article, the cost of the transmission and necessary components can be a large expense. The automatic swap has also proven to be more time consuming.

The 3.4L, 5VZ-FE was released mid-year 1995 into Tacoma trucks and T100 trucks. It is the successor to the 3.0L, 3VZ-E. The engine code means that it is the 5th engine in the "VZ" family. "F" represents dual overhead camshafts in each engine head. The intake camshaft is driven by the timing belt, which turns the exhaust camshaft by way of a "scissor" gear. Anybody who’s into Toyotas will know the "E" represents electronic fuel injection. This motor was also released into the 3rd generation 4Runners (1996-2002) and base model Tundras.

There are many advantages that lead people to use this power plant in place of other conventional choices. The 3.4L uses late model technology. It is lightweight yet powerful, producing 190HP at 4800 RPM and 220 ft-lb torque at 3600 RPM. It is equipped with a smooth Toyota multi-port fuel injection system using a distributor-less ignition system and OBDII diagnostics. Its dual overhead camshaft design makes it efficient on fuel and offers great opportunity for power upgrades. This motor LOVES forced induction modifications, such as the beloved TRD Supercharger system. This engine also fits very well into a Toyota truck or 4Runner. Because of its size and components the conversion can look "factory" if performed properly. Don’t forget- one huge advantage is the "cool factor" of swapping in a late model Toyota motor!

Although the 5VZ-FE has been around for years it has many versions varying by model and year. There are several things to be aware of when considering this swap and purchasing the ORS conversion kit.
Back To Top

Transmissions

This kit will not allow the use of your original transmission. The 3.0L and 3.4L trucks both use an A340 automatic transmission. Although these transmissions use the same transmission codes, they are very different from each other. The valve body layout and electronic drive systems are very different and not compatible. These transmissions are driven by their respective ECU’s (Engine Control Unit, or computer). The 3.4L requires the use of the ECU from the 3.4L donor vehicle; thus requiring the use of an A340 automatic transmission from the 3.4L donor vehicle. If the conversion is being performed on a 4WD vehicle, it will be necessary to use a 4WD 3.4L donor vehicle.

This, of course, will incur an extra cost. Fortunately, it is not all a waste. The later version of the A340 coupled with the 3.4L is an improved version of the old. It sports a more responsive and efficient torque converter. It is also stuffed with upgraded clutches and brakes for more holding power. Needless to say, it is a stronger, better performing transmission.

The transfer cases behind the 3.4L A340’s have the front drive output on the driver side, opposite of all ’95 and earlier Toyota 4x4’s. The transfer case behind the 3.0L A340 is hydraulically driven by that transmission and cannot be separated from that transmission. For this reason our 3.4L conversion kits are sold with an adapter that allows the installation of an earlier gear-driven transfer case to the 3.4L auto transmission. This transfer case is not only stronger than both V6 versions but also has the front drive output on the passenger side. This transfer case is found in ’79-’95 4 cylinder manual transmission Toyota 4x4’s. The transfer case is then modified to a 23 spline input shaft and a top-shifting configuration.

The external dimensions of the 3.4L A340 are similar to that of the 3.0L automatic transmission. In some cases, driveline lengths are similar enough to allow the use of the stock drivelines. However, there are some cases when driveline lengths and flange bolt patterns will need modification. It is a good idea to plan this into the project budget. The transmission cross-member will also require modifications to accommodate this new drive train.

The use of a 3.4L A340 transmission will also require the use of a different shifter assembly. This shifter will also need to come from the 3.4L donor vehicle. The instructions included in the conversion kits detail how to fit this newer shifter mechanically and electrically.

The use of a 3.4L A340 transmission will also require the use of a different shifter assembly. This shifter will also need to come from the 3.4L donor vehicle. The instructions included in the conversion kits detail how to fit this newer shifter mechanically and electrically.

It is extremely important that all parts are purchased from the same donor vehicle. When doing an automatic transmission 3.4L conversion, all parts will need to come from a 3.4L donor vehicle with an automatic transmission. Toyota made changes to the electronics, sensors, and wiring configurations every year and to every model within each year. This makes it nearly impossible to match parts from different donor vehicles. Properly matching parts is also necessary for Off Road Solutions to provide conversion kits and wiring harnesses that function properly.
Back To Top

Wiring

The wiring is possibly the most complicated part of this conversion. The 3.4L fuel injection system is entirely different from that of the older Toyotas. This means all the electronics that Toyota gave the 3.4L will have to be in place in your older Toyota in order to make this engine purr. Unfortunately, the electronic EFI components from your older Toyota 3VZ or 22R will be useless in this swap.

There are 3 primary parts of this fuel injection circuit. The first is the engine wiring harness. This is the harness that is primarily attached to the engine. This is sometimes called the injector harness. This harness connects to engine components like the fuel injectors, ignition coils, air flow meter, etc. and then carries the wires into the passenger compartment through the passenger side firewall.

The second main part is the Engine Control Unit, or ECU. This is also called the Engine Control Module, or ECM. Sometimes it is just called the computer. I guess we like to call it the ECU. This is the heart of the fuel injection system. This maze of solid state circuitry uses various input signals to control the engine electronics.

The third main part of the 3.4L electronic fuel injection circuit is the body harness. This is sometimes called the "dash" harness or the main harness. This harness is the largest harness in the vehicle and carries the majority of the entire vehicle’s circuits. About 40% of the fuel injection’s circuit is contained in this complicated harness.

The engine wiring harness and ECU are easy to install in another vehicle when performing this swap, but the real challenge comes about when it’s time to take care of that last 40%. That is when Off Road Solutions comes in. We offer a conversion harness that is designed to provide that last 40% of the 3.4L fuel injection circuit. This harness connects to the 3.4L ECU and engine wiring harness, then plugs directly into your older Toyota. In some cases it will even act as a stand-alone harness that completes the engine circuit. Either way, the original wiring in your older Toyota will not have to be torn apart or changed in order to accommodate this new engine. It’s really cool. The alternative is to re-wire your entire vehicle with a newer body wiring harness. The ORS conversion wiring harness will save you an enormous amount of time and heartache. Trust us, we’ve tried other ways.

The ORS conversion harness is found in every conversion kit and is also sold separately. There are many discrepancies in factory wiring configurations between years and models. This makes it very important to match the ORS conversion harness to your conversion. This is another great reason to purchase all the donor parts from the same vehicle.
Back To Top

Oil Pan

Most 3.4L engines are equipped with an oil pan that will not fit the suspension of an older Toyota. If your 3.4L came from a T100, you may be in luck. If your 3.4L came from a Tacoma, 4Runner, or Tundra, you will have to swap out your oil pan to fit this engine into your older Toyota. The oil sump on the above applications is in the front of the engine, right where your steering and differential like to hang out. An oil pan from a V6 equipped T100 will have to be used in this conversion. A 4WD T100 pan will work well with 4WD IFS trucks, and a 2WD T100 oil pan works well with live axle 4WDs and 2WDs. The oil pan accessories, such as the oil sump and dipstick parts will also need to be replaced to accommodate this new oil pan. Coincidentally, the oil pans found on the 3.0L engines are the same pans from the V6 T100s. 4WD and 2WD applications work the same. However, if using a 3.0L oil pan, the oil sump and dip stick hardware need to come from a 3.4L T100 application. These parts can also be found in most Off Road Solutions 3.4L conversion kits.

Another concern is the oil dipstick placement. All Tacoma, 4Runner, and Tundra models have the dipstick placed in the front of the motor, in the oil pump housing. During the conversion, the dipstick will be moved toward the rear of the engine to accommodate the conversion oil pan. 1999 and earlier models have a machined hole with a removable plug where the dipstick will be installed. In 2000 and later models this hole no longer exists and will need to be drilled to perform the conversion. If curious when shopping for an engine, inspect the block directly underneath the driver side engine mount just above the oil pan for the plug (see illustration).

Back To Top

Exhaust

There are many ways that the exhaust system can be done in this conversion. It is popular to use the factory exhaust manifolds from the 3.4L engine. The OEM 3.4L exhaust uses a crossover pipe that ties the two manifolds together behind the engine, above the bell housing. This pipe, however, exits on the passenger side. It is more difficult to route the exhaust down the passenger side, due to brake and fuel lines, the transfer case, and the fuel tank. ORS offers a custom crossover pipe similar to the 3.4L OEM unit, but routes both banks to the driver side. This will allow a cleaner and easier exhaust system installation. This "dumps" the exhaust on the proper side of an older Toyota, and keeps the undercarriage free of any crossover exhaust pipes. When ordering an ORS crossover pipe, note the year of the donor engine. This will denote the type of exhaust manifolds on the engine (either can be used).

If performance exhaust is desired, we recommend using the Downey header system with a custom built exhaust system. When using the Downey system, exhaust will need to be routed down both sides of the bell housing to a custom crossover pipe underneath the vehicle. Earlier Toyotas were designed to have the exhaust routed down the driver side of the vehicle. With this header setup care must be taken when routing the exhaust down the passenger side to be clear of fuel lines, brake lines, and the front drive shaft (and don’t forget the fuel tank too).

Once the headers or factory manifolds are in place, a custom exhaust will need to be built on your vehicle. If emission regulations are a concern, it is the customer’s responsibility to research the local regulations to ensure the modifications will be legal. If the donor vehicle had 2 catalytic converters, 2 converters need to be installed in order to satisfy the ECU’s emission controls. If the donor vehicle only had 1 converter, 1 good replacement will suffice. 2 oxygen sensors are needed. 1 will be placed before the catalytic converter(s), but after the crossover. The other will need to be placed after the catalytic converter(s). We strongly recommend using Toyota or OEM quality replacement oxygen sensors. The choice of muffler, materials, diameter, etc. will be up to the customer. We recommend using a 2.25" or 2.5" diameter, depending on your performance plans. Most local exhaust shops should also be able to build a mandrel or traditional system tailored to your needs.

We are often asked if the catalytic converters and oxygen sensors are needed. Our answer is yes. This fuel injection system is designed to have 2 oxygen sensors and 1 or 2 catalytic converters. The OBD2 diagnostic system can detect if an oxygen sensor or a catalytic converter is missing or faulty. If so, the ECU will operate on a different fuel map, causing a loss in performance in order to conserve fuel (and reduce emissions) until the condition is corrected. This engine will run better with these emission systems properly installed. Besides, we don’t need to stink up our outdoor playground any more than necessary, do we?
Back To Top

Hood Clearance

Another concern we have found is that this engine is physically too tall to fit under the hood of your vehicle without modifications. The intake plenum is taller than that of the 3VZ-E, not allowing the assembly to fit between the suspension and the hood. We have found that a small amount of hood trimming or a 2" body lift will cure this problem. In most cases we have found that a small hood scoop will cover the hole cleanly. The necessary clearance hole is a little larger on the ’84-’88 body style. Body lift kits and hood scoops are available through Off Road Solutions.

Recommended Hood Scoop Installed

Hood cut performed on ’84-’88 body style

Back To Top

Donor Parts

When shopping for the parts in this conversion, there are a few groups of parts to consider.
  • The first is the engine itself and the OEM parts associated with it. These parts are not provided and are usually found in a salvage yard.
  • The second is the conversion parts. ORS offers different conversion kits, depending on the customer’s needs. Many of these parts cannot be found on the donor or recipient vehicle, but are necessary to perform the swap. Some of these parts are not necessary, but very helpful when doing a conversion.
  • The third group to consider is not necessary, well not for some... Performance stuff. Headers, supercharger, ORS crossover pipe, tuning kits... You get the idea. This would be a great time to add this stuff.
A few Goodies for a "faster" conversion.

Downey Headers

This is a list of the OEM parts needed, including the engine. These parts are NOT included in our kit and will need to be provided by the customer from a 5VZ-FE equipped vehicle. New parts can be used, however, used parts are most common. The used parts market price of this list can vary greatly. We’ve seen this list sell from $1200-3500. If the 3.4L conversion is being performed on a 4WD vehicle, the donor vehicle will also need to be a 4WD.
  • 5VZ-FE longblock- new, remanufactured, or used
  • Both exhaust manifolds and crossover pipe (unless using a header system)
  • Intake manifold
  • Intake plenum with throttle body
  • All items on motor related to fuel injection such as injectors, fuel rail, vsv’s, sensors, throttle body, etc.
  • Alternator and brackets
  • Power steering pump and brackets
  • A/C compressor and brackets
  • Spark plugs
  • Spark plug wire set
  • Cylinder coil packs (3)
  • Engine (injector) wiring harness
  • ECU (computer)
  • Igniter assembly (flat, square shape, usually black, near intake box)
  • Intake system- tubing, air box, air filter. If upgrading to an aftermarket intake system, only the air flow meter mounting tube and hardware will be necessary.
  • Evaporative canister (optional)
  • Evaporative vapor pressure sensor
  • Evaporative vapor pressure VSV
  • Evaporative purge VSV
  • Starter
  • Air flow meter
  • Oxygen sensors (2), post and pre-cat
  • Automatic transmission assembly w/ torque converter
  • Shifter assembly (floorboard)
  • Transmission cooler hard lines (2)
  • Transmission lower inspection (dust) cover
  • Drive plate and mounting hardware
  • Torque converter x drive plate mounting bolts
  • Gear driven transfer case - 23 spline, top shifting configuration***
  • Rubber mount from gear driven transfer case
  • OEM oxygen sensor exhaust ports (welded to pipe)
  • All the OEM hardware you can get your hands on...
***A transfer case with this configuration was never manufactured by Toyota. Gear driven cases with a 23 spline input are only found in 22R-TE (turbo) 4WDs equipped with a manual transmission. These were never "top shifting," meaning the shifter exits straight out of the top of the transfer case. Top shifting cases can be found in all ’79-’83 4WD trucks and ’85-’88 4WD fuel injected trucks and 4Runners. To complete this swap, a case will need to be modified to meet these qualifications.
The following parts will need to be re-used from your vehicle (or a 3.0L equipped vehicle), if in good condition. If these parts are not in good condition ORS can offer replacements.
  • Radiator- 3VZ-E application - yes, we use this one
  • 3.0L Shroud
  • 3.0L fan assembly
  • 3.0L fan clutch assembly
  • Engine Mount Brackets
  • Misc. OEM hardware
  • Oil pressure sending unit (if equipped with oil pressure gauge)
Back To Top

Conversion parts

Off Road Solutions offers 3 different 3.4L conversion kits for pre ’95 Toyota trucks and 4Runners. ORS also offers these parts separately. All Off Road Solutions 3.4L Conversion Kits are priced as a package. This saves the customer substantial money (and time) over buying the products separately. See the products section of our website for pricing information.

These kits work very well with 3.0L equipped vehicles. If the engine is being dropped into a ’86-’95 model with a 22R, our weld-on engine mounts are needed to prepare the frame for the V6.

Our conversion kits DO NOT include provisions for the exhaust system. If using the OEM manifolds, we highly recommend purchasing the ORS custom crossover pipe to make the installation much cleaner and easier. This is also not included in the kits.

The first conversion kit is the Full Kit. This kit includes many parts necessary for the conversion. Also included are parts that are not necessary, but useful to replace, like a clutch, oil pan, spark plugs, etc. This kit is VERY complete and is designed to prevent the customer from going to the parts store 20 times during the conversion. The idea is to literally open the box and perform the conversion (short of exhaust) with high quality new parts. These parts are package priced to save the customer money in the long run. We highly suggest the Full Kit for most installers. Please review what is included:
  • Conversion wiring harness
  • Transmission to transfer case adapter
  • High pressure power steering hose
  • High pressure fuel hose
  • Fuel return hose
  • Power steering return hose
  • Battery relocation tray
  • Engine mount isolators (rubber isolators)
  • Lower radiator hose
  • Upper radiator hose
  • Oil pan
  • Oil sump assembly
  • Oil sump gasket
  • Sealer for oil pan
  • Oil dip stick
  • Oil dip stick tube
  • Oil dip stick tube adapter
  • Oil dip stick tube O-ring
  • Transmission oil pan
  • Transmission oil pan dipstick tube
  • Transmission dip stick
  • Transmission pan sealer
  • Transmission cooler hoses
  • Heater hoses
  • Oil filter
  • Spark plugs
  • Alternator drive belt
  • Power steering drive belt
  • A/C drive belt
  • Oil pump housing plug
  • Tap for housing plug
  • Drain plug
  • Drain plug gasket
  • Large, medium and small hose clamps
  • Assorted hose and wire routing clamps
  • Misc. vacuum hose
  • Misc. zip ties
  • 8 gauge battery relocation cable
  • Fusible link wire
  • An extremely helpful set of instructions...
The second kit available is the Standard kit. This kit includes the essentials for performing the swap (short of exhaust). This kit is similar to the full kit but a few items were removed that can be re-used from the original vehicle or may not need replacement. Here are the items included in the Standard Kit:
  • Conversion wiring harness
  • Transmission to transfer case adapter
  • High pressure power steering hose
  • High pressure fuel hose
  • Fuel return hose
  • Power steering return hose
  • Battery relocation tray
  • Lower radiator hose
  • Upper radiator hose
  • Oil sump assembly
  • Oil sump gasket
  • Sealer for oil pan
  • Oil dip stick tube
  • Oil dip stick
  • Oil dip stick tube adapter
  • Oil dip stick tube O-ring
  • Heater hoses
  • Transmission oil pan dipstick tube
  • Transmission dip stick
  • Transmission pan sealer
  • Transmission cooler hoses
  • Oil pump housing plug
  • Tap for housing
  • Drain plug gasket
  • Large, medium and small hose clamps
  • Assorted hose and wire routing clamps
  • Misc. vacuum hose
  • Misc. zip ties
  • 8 gauge battery relocation cable
  • Fusible link wire
  • An extremely helpful set of instructions
The third kit offered is the Basic Kit. This kit includes the items exclusive to Off Road Solutions. These items are very helpful when doing the swap. Many other new parts will still be needed to complete the conversion. Here are the parts included in the Basic Kit:
  • Conversion wiring harness
  • Transmission to transfer case adapter
  • Upper radiator hose
  • Lower radiator hose
  • Heater hoses
  • High pressure power steering hose
  • High pressure fuel hose
  • Battery relocation tray
  • Oil pump housing plug
  • Tap for housing
  • An extremely helpful set of instructions
It is the sole responsibility of the customer to provide Off Road Solutions with the necessary information from the donor and recipient vehicles. Having the proper information is the only way for Off Road Solutions to ensure that the provided parts will function properly. The information needed by ORS at the time of order is: Donor vehicle - VIN number, production date, model, 4WD or 2WD, Transmission type. Recipient vehicle - VIN number, production date, model, 4WD or 2WD, original engine type, suspension setup, ABS or no, transmission type.
Back To Top

Average Costs

Here is a rough idea of the money you may spend on this swap:

Using ORS Full Conversion Kit
Engine and OEM parts: $2,800
Conversion kit: $2,385
Exhaust parts: $750
Miscellaneous: $300
Total: $6,235

Using ORS Standard Conversion Kit
Engine and OEM parts: $2,800
Conversion kit: $1,700
Exhaust parts: $750
Miscellaneous: $300
Total: $5,550
Back To Top

Installation

Off Road Solutions offers full installation service for this conversion. We pride ourselves in performing a swap that looks OEM. We learned how to engineer an engine system from the masters - Toyota. We take the time to be sure that the parts are properly installed, wires and hoses are not rubbing sharp edges, and the swap is fully tested. We have no tolerance for leaks. We make sure that everything is installed properly so that it is not damaged and looks clean, like Toyota does. We can even add performance mods and build super clean exhaust systems for you new power plant.

Our work is billed on a time and materials basis. We charge the customer for the time and materials that it takes to complete the swap. As one can imagine, a nice engine swap can be time consuming, so the installation price is high. A complete swap takes about a week’s worth of time. That is about 50 hours, or about $4500 of labor.

Here are some average costs:
Engine and OEM parts: $2,800
Conversion kit: $12,385
Exhaust parts: $750
Miscellaneous: $300
Installation labor: $5,800
Total: $12,035
Back To Top

Another Word on this Conversion

Engine swaps in general are expensive and time consuming. In comparison, we have found this to be one of the most economical and simplest conversions that can be done in an older Toyota. We also believe it to be one of the best.

We are often asked how one can save money performing this swap. We believe that doing this swap with one of our kits (whichever suits your need) is the best value. Unfortunately, there is not a conversion that can be done properly only using the parts in the donor and recipient vehicles. Parts that cannot be found on either vehicle are required to do a conversion properly, otherwise it would not be a "conversion." Yes, it is possible to "get by" without some of these parts by using parts that don’t fit well and cutting corners when needed. This normally causes great dissatisfaction down the road in the form of a failure. This also costs as much or more money in the long run. We truly believe there is no substitute for quality. An engine is only as reliable as the installation.

We’ve engineered our 3.4L Conversion Parts not only to aid in this conversion, but also to save the customer money and heartache.

With professional installation, this swap is not a good investment for those seeking a monetary return. Customers may never get this money back out of the truck, even when performing their own work. It can be cheaper to sell the older Toyota and purchase a newer Toyota with a factory 3.4L engine. This swap is for those who want something unique, those looking for a challenge, those who won’t let go of their older Toyota, those who have too much into their older Toyota anyway, those who just love the "cool factor", or all of the above!

Thank you for taking the time to check out our article. We hope it has been helpful!
Back To Top