Best 4Runner engine and tranny for FJ40... And could I keep the current tcase (1 Viewer)

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I'm not sure what your goal would be. The world of conversions isn't that far-reaching, or is it? But, I can really appreciate how the factory-4Runner drives, wheels, etc.

This is my incorrect answer. A Buick 3.8L V-6 Fireball, would be of interest, depending on the compatibility of flywheel? The bellhousing is supposedly akin to the SBC, but, the flywheel itself might be engine-specific. The later versions were the 'Buick 3800.' An '84 Buick Regal with a 3.8L V6 could get like 16-city, 22-mpg highway. Same for the 3800 that were used in front wheel drive cars, like the one in my folk's '92. The bore and stroke is not like the 2F, it is 'over-square' - meaning it can safely spin at a higher rpm. - short stoke. I think this would keep up with my buddies Gen 2 4Runner, that he let me wheel back in the day - a Buick engine with stock Toyota gears in an early 70's FJ40. Buuut, when you look at the history, it is actually a Jeep engine. Jeep Engine: Dauntless Buick 225 V6 - https://www.jeeptech.com/engine/dauntless225.html
 
I'm with Grayscale as far as why a 4Runner engine/transmission combination?

What are you hoping to gain?

I say that because when my ex-wife and I moved to Utah, she had a 1993 4Runner with the 3.0 V-6. It was Gutless. Some friends came out to visit, and unfortunately totalled her 4Runner. By then (1999) the 4Runner was a new body style with a newer, more powerful engine.

We test drove it, and were underwhelmed. That was disappointing because other than the lack of power, we liked the vehicle a lot. But the power deficit compared to other vehicles we looked at, was a dealbreaker.

The Internet in general, as well as 'Mud have a lot of information on engine swaps. I'm not aware that people are going out of their way to swap 4Runner power trains into anything. If you haven't done it, an engine swap is a lot of work. In my opinion, you are way ahead in dollars, time, and frustration by choosing an engine/transmission combination that is somewhat common... and it will still be expensive, time consuming and frustrating.

Especially with computerized, fuel injected engines, you want to be able to access the knowledge base of those who have done it. Conversion wiring harnesses, and computer re-flashing are only two parts of the process. There are many vendors of both for common engine swaps, as well as all kinds of aftermarket parts to make the swap easier.

I would encourage you to seriously consider your goals, your skill set, your budget, and your timetable before embarking on the journey of an engine swap.
 
I'm with Grayscale as far as why a 4Runner engine/transmission combination?

What are you hoping to gain?

I say that because when my ex-wife and I moved to Utah, she had a 1993 4Runner with the 3.0 V-6. It was Gutless. Some friends came out to visit, and unfortunately totalled her 4Runner. By then (1999) the 4Runner was a new body style with a newer, more powerful engine.

We test drove it, and were underwhelmed. That was disappointing because other than the lack of power, we liked the vehicle a lot. But the power deficit compared to other vehicles we looked at, was a dealbreaker.

The Internet in general, as well as 'Mud have a lot of information on engine swaps. I'm not aware that people are going out of their way to swap 4Runner power trains into anything. If you haven't done it, an engine swap is a lot of work. In my opinion, you are way ahead in dollars, time, and frustration by choosing an engine/transmission combination that is somewhat common... and it will still be expensive, time consuming and frustrating.

Especially with computerized, fuel injected engines, you want to be able to access the knowledge base of those who have done it. Conversion wiring harnesses, and computer re-flashing are only two parts of the process. There are many vendors of both for common engine swaps, as well as all kinds of aftermarket parts to make the swap easier.

I would encourage you to seriously consider your goals, your skill set, your budget, and your timetable before embarking on the journey of an engine swap.
To be honest I started with questions such as changing the gearing, rebuilding and boring the two f engine we have, and switching to a H55F transmission. From talking with people that have made that switch or those changes already it wasn't going to be a big change and drivability.

This FJ40 is something my son dad and I have worked on for 3 years and it is my son's daily driver while at college

I was just looking for something that is going to create more highway driveability

Each of my questions and answers from other people on mud brought up more questions
 
I was just looking for something that is going to create more highway driveability

The powertrain is the least of an FJ40's problem for drivability.

Terrible suspension.
Horrific CG
Dreadful wheelbase
Awful steering. Both mechanically and geometry.


I daily my 40 in the non-winter months, and I put a fair number of miles on it. I think I put 20k miles on it last year.
I love it, but it's a terrible vehicle in almost every metric. 🤣
I just have Dogshït taste in cars.
 
Actually, plenty of precedent for this:

5VZ-FE/R150/1F/adaptor from Marlin and split case and this would work.

It might actually be a pretty bad ass set-up
I would agree a 5vz would be not too bad. You could look around for an R151 from an LJ78 and get a split case upgrade to the t-case.
 
I'm with Grayscale as far as why a 4Runner engine/transmission combination?

What are you hoping to gain?

I say that because when my ex-wife and I moved to Utah, she had a 1993 4Runner with the 3.0 V-6. It was Gutless. Some friends came out to visit, and unfortunately totalled her 4Runner. By then (1999) the 4Runner was a new body style with a newer, more powerful engine.

We test drove it, and were underwhelmed. That was disappointing because other than the lack of power, we liked the vehicle a lot. But the power deficit compared to other vehicles we looked at, was a dealbreaker.

The Internet in general, as well as 'Mud have a lot of information on engine swaps. I'm not aware that people are going out of their way to swap 4Runner power trains into anything. If you haven't done it, an engine swap is a lot of work. In my opinion, you are way ahead in dollars, time, and frustration by choosing an engine/transmission combination that is somewhat common... and it will still be expensive, time consuming and frustrating.

Especially with computerized, fuel injected engines, you want to be able to access the knowledge base of those who have done it. Conversion wiring harnesses, and computer re-flashing are only two parts of the process. There are many vendors of both for common engine swaps, as well as all kinds of aftermarket parts to make the swap easier.

I would encourage you to seriously consider your goals, your skill set, your budget, and your timetable before embarking on the journey of an engine swap.
I was looking for an engine / tranny swap that would create more driveability. My son is a freshman at college right now. He absolutely loves the FJ, minus the high rev of highway speed, poor mpg, etc.

As stated before I looked at gear changes, rebuild motor but suped up, changing to H55F... and everyone said it wouldn't make that big of a change in highway benefits. I looked at swapping the motor to a diesel mated with the H55F and ran into availability issues for a Toyota diesel. I didn't want to spend $15k for a 2.8 cummins. It looks like the VW 1.9 TDI could be an option, but haven't fully vetted it yet. I am doing that here on MUD.

I thought that a newer Toyota engine mated with a higher gear ratio tranny would make a bigger difference, but didn't know how much of a pain in the ass it would be

You guys are correct... there is nothing great about the FJ40 wheelbase, suspension, pushing a square object through the air fast isn't efficient... but it sure does look badass.

to everyone that has responded, thank you for your input and thoughts. it has helped a lot.
 
If you settle on an idea of "This power train is what I want," you should get an example of that vehicle, mount a piece of plywood to the roof to simulate the FJ40 windshield, and drive it around for a few weeks to see what kind of mpg you get.
If you pick a 4Runner, you might also need to add about 1,000lbs for accuracy.
 
If you settle on an idea of "This power train is what I want," you should get an example of that vehicle, mount a piece of plywood to the roof to simulate the FJ40 windshield, and drive it around for a few weeks to see what kind of mpg you get.
If you pick a 4Runner, you might also need to add about 1,000lbs for accuracy.
LOL... yeah pretty much. my original questions lead to other questions.... which lead to other questions! And here we are!
 
The 2F is tough, simple, reliable, and easy to work on, which is the whole point of an FJ40 to begin with. If you want to tilt things in favor of performance though I'm sure an EFI conversion and the 5 speed will make a dramatic difference.
 
The 2F is tough, simple, reliable, and easy to work on, which is the whole point of an FJ40 to begin with. If you want to tilt things in favor of performance though I'm sure an EFI conversion and the 5 speed will make a dramatic difference.
I doubt it. I think dramatic is a stretch.
 
Yeah probably not the best word choice. Maybe not "dramatic", it'll still be the same vehicle, but it'd be noticeable
 
2F
 
Any provisions for an e-brake, or parking brake? I should disclose that I probably need to seal mine up from intrusion of gear oil, but, we are talking "best," not for typical service.

I think that a carburetor is more correct to the original vehicle, and therefore better as a rugged, yet simple, build. That is why I'd at least consider the Buick V6, if possible. Many of the benefits of an SBC, but, minus two cylinders to route exhaust from and keep cool. Also, it retains the stock transfercase, with parking brake. The intake manifold on the Buick is water-heated directly from the heads, so it probably could work in a simple desmog configuration, in ways that the 2F struggles. The 5VZ-FE, a '95, I think that we tripped all the codes when my buddy installed an aftermarket oil-bath air filter, and a cold-air intake.
 

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