This is a slimmed down version of a thread I used to have on another site. I hope it helps someone attempting a similar swap. I will add more as time allows.
My truck 1985 4Runner SR5 22RE(bought in 1997), 33x10.5x15, (now 35x12.5x15) 5.29s, W56-A trans, single case marlin gears, ARB front/rear, 86 rear axle, marlin crossover steering, other random stuff
Donor truck 2001 Tacoma Prerunner Auto that had been rolled but only had 25,000 miles.
Oil pan, bellhousing, flywheel, clutch, slave and airbox from a 1995 T100 at the junkyard.
Manual ecu from ebay
TOS (toy only swaps) motor mounts(chilkat mounts did not work for me)
22RE oil pressure sender
A/C clutch/pulley from a 1986 MR2
Dipstick tube from Toyota
New flywheel bolts from Toyota (they are not reusable)
Toyota belts, front/rear main seals, valve cover gasket, water pump, fuel filter, throwout bearing, pilot bearing
Plastic 22RE heater valve 89-95
My goal was to keep this motor as stock as possible so it could not only be reliable but easily and accurately serviced via obdII scan tools. I live in California and need to have it pass the Referee.
THINGS TO GET FROM DONOR (2001)
-engine with complete harness
-cat(s) with o2 sensors (as much of the exhaust as possible
-wiring for rear o2
-under hood fuse box (early Tacos under dash fuse box also)
-clutch slave and line
-bell housing, flywheel, clutch, fork
-charcoal canister(evap box)
-fuel, return, vent lines to tank
-IK2 dash harness plug to plug into engine harness IK2
-obdII plug
-remove battery tray with spot weld bit if moving battery
-exhaust heat shields
-heater hoses but need a different heater valve 87240-89124
-throttle cable
-air box and fender snorkel
3rz/2rz Types
From what I've learned, there are three main versions of these motors with possible slight differences throughout
95.5-97.6- distributor
97.6-2000- 2 coil pack
2001-2004- 4 coil (COP) 2 cats, header type manifold
(4 coil started in 2000 in California)
GENERAL NOTES
A lot of people perform this swap quickly, don't take the time to prep vehicle, and don't connect as many of the wires as I do. (It really doesn't take very many connections to make it run) If you're trying to do this swap quickly, you may want to stop reading now. This is for those who want everything to work like it was stock.
2RZ/3RZ
I would not hesitate to use a 2rz as opposed to a 3rz. It doesn't make quite as much power but is still a modern update from a 22R/RE (twin cam, obd) and has the advantage of not having balance shafts like the 3rz which some choose to remove using a Kit. I kept mine.
Like all great Toyota engines, there is always at least one problem area, the exhaust valves.(some might say the balance shafts can also be a problem) The 2rz/3rz exhaust valves tighten up over time. Make sure to check your valve clearances. Burnt Exhaust Valves are common causes of failure on these engines if not checked and adjusted periodically. If your exhaust clearances are still in spec but on the tight side, I would adjust them a bit looser. The 3rz uses disc over bucket style shims. You can harvest shims at a junkyard so you'll have a bunch of different ones on hand when you do the work. I used a rounded and smoothed flathead screwdriver to push the bucket down and a SCHLEY SL88251($15) spacer wedge to hold it down in order to remove the shims(using a magnet) with the cams in place. 3rz valve adjustment
Cold adjustment IN=0.15-0.25mm (0.006-0.010in.) EX=0.25-0.35mm (0.010-0.014in.)
Here is a junkyard list of all Toyotas that use the same valve shim discs.
Swapping into 95 and older trucks:
A 3rz/2rz will fit in straight axle mini trucks with the addition of a t100 3rz oil pan/pickup/dipstick tube. For IFS you will have to make a custom t100 oil pan or find a company that makes/modifies them as it will hit some front diff areas. IFS Oil Pan Update I have heard from another Mud member that you can use and oil pan and pickup tube from a 3rz Landcruiser Prado. 12101-75090 oil pan. 15104-75090 pickup tube. 15301-75011 dipstick. A 3rz/2rz bellhousing will bolt right up to the W or G series trans found on most 4cyl trucks. If you have a 3.0 v6 it is far easier to do a 3.4 swap as it bolts right up to the R series trans and as far as I know uses the factory motor mounts. The 3.4 swap normally requires slight hood clearancing without a body lift. If you want to mate a 3rz/2rz to an R series trans you will need a 2tr manual bell housing from 05 and up 4cyl tacoma
Motor mounts
Some people buy them, some people make them. it's up to you. I prefer the TOS ones.
Air filter box
If you're going to move the battery to the other side, you'll have room for a stock air box. Some people leave the battery and just use an open cone filter which I don't like because it's right above the exhaust manifold (hot air) and doesn't protect from water intrusion.
The 3rz air filter box is too tall for the older trucks. I cut the bottom out of a T-100 box and fiberglassed it to fit.
The best solution is an airbox out of certain 99-2004 3.4 tacomas that can be identified because the filter loads from the top like toast in a toaster and has a flap you lift to insert it. An aftermarket one only costs around $70 new.
Heater
-Retaining the rear heater (4runner) was not worth it to me although it can be done later with some Y style connections. The early 80’s style 4runner metal heater valve with rear heater does not work for the swap (although some squeeze it in), it will hit the backside of the 3rz, remove it before test fitting the new motor. A later style plastic heater valve is the one to use. It came on 89-95 pickups and 4runners with 22r, 22re and 3.0 part number 87240-89124. Pre Tacoma trucks/4runners use heater valves with a push/pull operation. The taco heater valve can't be used because it is a left/right operation and would require a longer push rod. It is important to figure out the heater connections before final motor install because of how tight the area is. You want to make sure your heater hoses aren't in contact with hot exhaust egr tubes or any sharp edges which is hard to do in that space.
Fuel Lines
-I used the gas, vent, and return line from the Tacoma however you can buy a 5/16 line and a 5/16 fuel line compression fitting just remember to remove the coating on the Toyota line down to bare metal before installing the fitting(high pressure line)
Clutch
-I have read many posts regarding the clutch when mating the G or W series trans to the 3RZ. Some people used the 22RE fork and throwout bearing, some used the 3RZ fork with the 22RE throwout and some used all 3RZ parts like I did. Most used the 3RZ slave and kept the 22RE master.
Brake Booster
If you haven't upgraded your booster by now, there is no better time. I would recommend the dual diaphragm booster that came on the 3.0 4runners and others. You may need a spacer on 84-85 but slight grinding is all I needed. I don't recommend the turbo booster because it may hit the 3RZ intake. 83 and older trucks require more creative solutions
Oil pressure gauge
you need to get/reuse the oil pressure sender from the original motor(if it had a gauge) and replace the 3RZ oil light sender with it. As far as I know, the tacos only had an oil light on the dash, never a gauge. I have heard you can ruin your original gauge if you connect the 3RZ sender to it. Note: the 3rz oil pressure is much lower than the 22re and reads between low and a quarter most of the time on mine and others I've questioned.
Tach gauge and Vehicle speed sensor
I used the 10k ohm resistor mod to get the original tach to read correctly.
The speed sensor wire (VSS or SP1) should be connected to the 3rz ECU. It is easy to find on a 22RE as it originally went to the 22RE ECU and cruise control computer. I have heard that a lot of toyota gauges have the VSS built into them whether it's used or not. On my truck it was a green wire/blue stripe connector B pin 4 on the gauge diagram below. My VSS signal is created in the cluster from my speedo cable, many other trucks have an electronic sensor
at the transmission which is wired into the cluster which then creates the VSS signal. It may take additional work to get a VSS signal if you are swapping clusters and/or transmissions. You're not going to be able to wire an electronic VSS sensor into a cluster that has a speedo cable input but you may be able
to add an electronic VSS to a trans that had a speedo cable originally.
Stop/Brake signal
The stop signal (STP) also needs to be connected to the 3rz ECU. It, together with the VSS plays a crucial role on decel fuel trim/cut. The ECU needs to know if you are still moving when you let go of the gas pedal, also if you are still moving when you apply the brakes. Here is a quote from Toyota
"Stop Light Switch (STP) The stop light switch input to the ECU is used to modify the deceleration fuel cut program when the vehicle is braking. Whenever the brake pedal is depressed, fuel cutoff and resumption rpm is reduced to improve driveability characteristics of the vehicle. In the event the STP signal is lost, fuel cut will take place at a standard deceleration speed, causing an objectionable feel when fuel is cancelled."
I have seen threads where people don't think it's necessary to connect the VSS or STP wires to the ECU but I think you should.
Very important
-Move the brake lines on the firewall towards the passenger side as much as possible then move the same lines from the side of frame to the top of the frame to avoid heat from the cat/exhaust manifold.
Heat shielding
-Add heat shielding to passenger firewall and down following exhaust route. I used "floor and tunnel heat shield barrier adhesive backed" along with the regular metal shielding I installed once the exhaust was in. This is very important as the manifold ends up very close to the firewall and will literally melt the carpet in the inside of the passenger cab as well as provide permanent heat. You’ve been warned.
Radiator & Fan
I used a three row aluminum radiator for a 2wd 3.0 pickup (dpi-1190), a 2wd 2RZ fan shroud modified to fit, and kept the 3RZ fan. I originally used the 22RE fan, clutch, and shroud on the 3RZ but it got hot a couple of times, the larger 3RZ fan/clutch/2rz shroud fixed the issue. I made use of the 22RE cooling pipe to get around the alternator and used custom hoses top-gates 22808, bottom-gates 22827, and I think gates 22361 for the pump to pipe elbow.
My truck 1985 4Runner SR5 22RE(bought in 1997), 33x10.5x15, (now 35x12.5x15) 5.29s, W56-A trans, single case marlin gears, ARB front/rear, 86 rear axle, marlin crossover steering, other random stuff
Donor truck 2001 Tacoma Prerunner Auto that had been rolled but only had 25,000 miles.
Oil pan, bellhousing, flywheel, clutch, slave and airbox from a 1995 T100 at the junkyard.
Manual ecu from ebay
TOS (toy only swaps) motor mounts(chilkat mounts did not work for me)
22RE oil pressure sender
A/C clutch/pulley from a 1986 MR2
Dipstick tube from Toyota
New flywheel bolts from Toyota (they are not reusable)
Toyota belts, front/rear main seals, valve cover gasket, water pump, fuel filter, throwout bearing, pilot bearing
Plastic 22RE heater valve 89-95
My goal was to keep this motor as stock as possible so it could not only be reliable but easily and accurately serviced via obdII scan tools. I live in California and need to have it pass the Referee.
THINGS TO GET FROM DONOR (2001)
-engine with complete harness
-cat(s) with o2 sensors (as much of the exhaust as possible
-wiring for rear o2
-under hood fuse box (early Tacos under dash fuse box also)
-clutch slave and line
-bell housing, flywheel, clutch, fork
-charcoal canister(evap box)
-fuel, return, vent lines to tank
-IK2 dash harness plug to plug into engine harness IK2
-obdII plug
-remove battery tray with spot weld bit if moving battery
-exhaust heat shields
-heater hoses but need a different heater valve 87240-89124
-throttle cable
-air box and fender snorkel
3rz/2rz Types
From what I've learned, there are three main versions of these motors with possible slight differences throughout
95.5-97.6- distributor
97.6-2000- 2 coil pack
2001-2004- 4 coil (COP) 2 cats, header type manifold
(4 coil started in 2000 in California)
GENERAL NOTES
A lot of people perform this swap quickly, don't take the time to prep vehicle, and don't connect as many of the wires as I do. (It really doesn't take very many connections to make it run) If you're trying to do this swap quickly, you may want to stop reading now. This is for those who want everything to work like it was stock.
2RZ/3RZ
I would not hesitate to use a 2rz as opposed to a 3rz. It doesn't make quite as much power but is still a modern update from a 22R/RE (twin cam, obd) and has the advantage of not having balance shafts like the 3rz which some choose to remove using a Kit. I kept mine.
Like all great Toyota engines, there is always at least one problem area, the exhaust valves.(some might say the balance shafts can also be a problem) The 2rz/3rz exhaust valves tighten up over time. Make sure to check your valve clearances. Burnt Exhaust Valves are common causes of failure on these engines if not checked and adjusted periodically. If your exhaust clearances are still in spec but on the tight side, I would adjust them a bit looser. The 3rz uses disc over bucket style shims. You can harvest shims at a junkyard so you'll have a bunch of different ones on hand when you do the work. I used a rounded and smoothed flathead screwdriver to push the bucket down and a SCHLEY SL88251($15) spacer wedge to hold it down in order to remove the shims(using a magnet) with the cams in place. 3rz valve adjustment
Cold adjustment IN=0.15-0.25mm (0.006-0.010in.) EX=0.25-0.35mm (0.010-0.014in.)
Here is a junkyard list of all Toyotas that use the same valve shim discs.
Swapping into 95 and older trucks:
A 3rz/2rz will fit in straight axle mini trucks with the addition of a t100 3rz oil pan/pickup/dipstick tube. For IFS you will have to make a custom t100 oil pan or find a company that makes/modifies them as it will hit some front diff areas. IFS Oil Pan Update I have heard from another Mud member that you can use and oil pan and pickup tube from a 3rz Landcruiser Prado. 12101-75090 oil pan. 15104-75090 pickup tube. 15301-75011 dipstick. A 3rz/2rz bellhousing will bolt right up to the W or G series trans found on most 4cyl trucks. If you have a 3.0 v6 it is far easier to do a 3.4 swap as it bolts right up to the R series trans and as far as I know uses the factory motor mounts. The 3.4 swap normally requires slight hood clearancing without a body lift. If you want to mate a 3rz/2rz to an R series trans you will need a 2tr manual bell housing from 05 and up 4cyl tacoma
Motor mounts
Some people buy them, some people make them. it's up to you. I prefer the TOS ones.
Air filter box
If you're going to move the battery to the other side, you'll have room for a stock air box. Some people leave the battery and just use an open cone filter which I don't like because it's right above the exhaust manifold (hot air) and doesn't protect from water intrusion.
The 3rz air filter box is too tall for the older trucks. I cut the bottom out of a T-100 box and fiberglassed it to fit.
The best solution is an airbox out of certain 99-2004 3.4 tacomas that can be identified because the filter loads from the top like toast in a toaster and has a flap you lift to insert it. An aftermarket one only costs around $70 new.
Heater
-Retaining the rear heater (4runner) was not worth it to me although it can be done later with some Y style connections. The early 80’s style 4runner metal heater valve with rear heater does not work for the swap (although some squeeze it in), it will hit the backside of the 3rz, remove it before test fitting the new motor. A later style plastic heater valve is the one to use. It came on 89-95 pickups and 4runners with 22r, 22re and 3.0 part number 87240-89124. Pre Tacoma trucks/4runners use heater valves with a push/pull operation. The taco heater valve can't be used because it is a left/right operation and would require a longer push rod. It is important to figure out the heater connections before final motor install because of how tight the area is. You want to make sure your heater hoses aren't in contact with hot exhaust egr tubes or any sharp edges which is hard to do in that space.
Fuel Lines
-I used the gas, vent, and return line from the Tacoma however you can buy a 5/16 line and a 5/16 fuel line compression fitting just remember to remove the coating on the Toyota line down to bare metal before installing the fitting(high pressure line)
Clutch
-I have read many posts regarding the clutch when mating the G or W series trans to the 3RZ. Some people used the 22RE fork and throwout bearing, some used the 3RZ fork with the 22RE throwout and some used all 3RZ parts like I did. Most used the 3RZ slave and kept the 22RE master.
Brake Booster
If you haven't upgraded your booster by now, there is no better time. I would recommend the dual diaphragm booster that came on the 3.0 4runners and others. You may need a spacer on 84-85 but slight grinding is all I needed. I don't recommend the turbo booster because it may hit the 3RZ intake. 83 and older trucks require more creative solutions
Oil pressure gauge
you need to get/reuse the oil pressure sender from the original motor(if it had a gauge) and replace the 3RZ oil light sender with it. As far as I know, the tacos only had an oil light on the dash, never a gauge. I have heard you can ruin your original gauge if you connect the 3RZ sender to it. Note: the 3rz oil pressure is much lower than the 22re and reads between low and a quarter most of the time on mine and others I've questioned.
Tach gauge and Vehicle speed sensor
I used the 10k ohm resistor mod to get the original tach to read correctly.
The speed sensor wire (VSS or SP1) should be connected to the 3rz ECU. It is easy to find on a 22RE as it originally went to the 22RE ECU and cruise control computer. I have heard that a lot of toyota gauges have the VSS built into them whether it's used or not. On my truck it was a green wire/blue stripe connector B pin 4 on the gauge diagram below. My VSS signal is created in the cluster from my speedo cable, many other trucks have an electronic sensor
at the transmission which is wired into the cluster which then creates the VSS signal. It may take additional work to get a VSS signal if you are swapping clusters and/or transmissions. You're not going to be able to wire an electronic VSS sensor into a cluster that has a speedo cable input but you may be able
to add an electronic VSS to a trans that had a speedo cable originally.
Stop/Brake signal
The stop signal (STP) also needs to be connected to the 3rz ECU. It, together with the VSS plays a crucial role on decel fuel trim/cut. The ECU needs to know if you are still moving when you let go of the gas pedal, also if you are still moving when you apply the brakes. Here is a quote from Toyota
"Stop Light Switch (STP) The stop light switch input to the ECU is used to modify the deceleration fuel cut program when the vehicle is braking. Whenever the brake pedal is depressed, fuel cutoff and resumption rpm is reduced to improve driveability characteristics of the vehicle. In the event the STP signal is lost, fuel cut will take place at a standard deceleration speed, causing an objectionable feel when fuel is cancelled."
I have seen threads where people don't think it's necessary to connect the VSS or STP wires to the ECU but I think you should.
Very important
-Move the brake lines on the firewall towards the passenger side as much as possible then move the same lines from the side of frame to the top of the frame to avoid heat from the cat/exhaust manifold.
Heat shielding
-Add heat shielding to passenger firewall and down following exhaust route. I used "floor and tunnel heat shield barrier adhesive backed" along with the regular metal shielding I installed once the exhaust was in. This is very important as the manifold ends up very close to the firewall and will literally melt the carpet in the inside of the passenger cab as well as provide permanent heat. You’ve been warned.
Radiator & Fan
I used a three row aluminum radiator for a 2wd 3.0 pickup (dpi-1190), a 2wd 2RZ fan shroud modified to fit, and kept the 3RZ fan. I originally used the 22RE fan, clutch, and shroud on the 3RZ but it got hot a couple of times, the larger 3RZ fan/clutch/2rz shroud fixed the issue. I made use of the 22RE cooling pipe to get around the alternator and used custom hoses top-gates 22808, bottom-gates 22827, and I think gates 22361 for the pump to pipe elbow.
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