Regearing to 4.56 Gears on the 5th Gen 4Runner

3000 Mile In-depth Review: Regearing to 4.56 Gears by East Coast Gear Supply On the 5th Gen 4Runner

3000 miles ago, I re-geared my 2016 4Runner to 4.56 Gears using East Coast Gear Supply’s Assembled 3rd Members.

I’ll talk about why I did it, the pros and cons and some of the technical details.

But first, let’s understand a little bit more about re-gearing like when it’s needed, why it’s done, and what it accomplishes.

The Set-Up

• East Coast Gear Supply 3rds Members for 5th Gen 4Runner: Check Price

The Dilemma

Let’s be honest, the stock 4400-lb 5th Gen 4Runner pushing out 270hp and 278 lb-ft torque was never zippy, to begin with. And, after all your mods and gear acquisitions, it now feels even slower than molasses.

So, let’s say you’ve lifted your truck 2 or 3 inches, added heavier oversized AT or mud tires…

Maybe you’ve even added some body armor, a metal bumper, winch, rear tire swing, an onboard fridge, a second battery, and/or a roof rack.  Your truck now looks like a beast on the road and it’s now a very capable machine in the off-road environment too!

But there’s a downside…

Your truck brick-in-the-wind is probably searching for gears on hill climbs or even while trying to cruise by slower traffic in the fast lane on a flat highway.

Your MPGs drop a bit as the engine is working harder to fully rotate those larger wheels, and your driving experience (although subjective) probably suffers a bit.

So, why is this happening?

Well, your truck might now be somewhere between 500-1500 pounds heavier when not under load and it now has considerably more frictional resistance and wind resistance to deal with when driving.

In technical terms, you’ve increased the mass of your vehicle and you now need more torque if you want your acceleration, shifting points, and power band to feel “normal” again.

Without getting overly technical, this dilemma occurs because the larger tires and added weight reduce the thrust that moves your truck forward.

In short, more torque is needed to get your oversized tires rotating and your vehicle to overcome the drag from the added weight and frictional/wind resistance.

Your truck hasn’t actually lost power, but it is definitely now working harder to turn those wheels!

As a result, your drivetrain and power band probably feel weaker and out of balance.  Transmission shifting points will feel out-of-whack too.

For some, that constant driving experience is a small price to pay and isn’t bothersome, for others it’s just unbearable.  I raised my hand to the latter of the two.

You, yourself, will probably compensate for the loss in torque by pressing the tall-skinny pedal a bit more.

Your truck will try to compensate at times by downshifting and “searching for gears” to provide more torque to the wheels as well.

At the end of the day, unless you restore the torque that was lost due to larger tires and added weight, your truck (depending on your specific set up) will constantly feel sluggish and underpowered and even more-so when under-load.

If you enjoy technical reading, math formulas, Newton’s laws, and would like to understand crawl ratio, torque, gearing, and all the science behind it much more in-depth, I highly suggest this article by Jalopnik—Crawl Ratios and Off-Road Gearing

Now we get it… So, Let’s Take a Look at the Solutions

The Potential Solutions

If you find yourself in the middle of this dilemma, there’s a handful of small to medium performance mods you can do.

Said mods have pretty minimal “gains” in the HP and torque areas but are still worth considering.

To find out more you can read our full round-up on 5th Gen 4Runner performance mods.

For the potential solutions…

Performance mods and upgrades like CAI, Catback exhaust, and headers may help a little.

However, there are really only two feasible options that instantly re-balance your power band, restore torque back to the wheels, and bring the shifting points back to normal.

Your Two Options:  Supercharge or Re-Gear

Both options provide more torque to the wheels, but in different ways:

• Supercharger basically increases your engine’s actual HP/torque output.
• Re-gearing increases torque by allowing the engine’s available power to transfer and rotate the wheels more easily.

Take, for example, the need to un-tighten a nut that is stuck on a bolt.  You can either push harder on the wrench or use a longer wrench to turn the nut “easier.”

Adding a supercharger to your truck would be equivalent to adding an extra set of hands to physically push harder on your wrench to get the bolt to finally come loose.

Re-gearing your truck would be like switching to longer wrench and using leverage to get it loose.

With the latter option, you use the same amount of “muscle” originally used… But we all know that the longer the wrench handle, the “easier” it is to turn and loosen the bolt due to the laws of leverage.

I, personally, already have the Magnuson Supercharger installed on my 4Runner, but I still also choose to re-gear to 4.56 and I’ll be reviewing this decision further below.

A NOTE ON THE SUPERCHARGER:  We aren’t going to cover the Supercharger option here, but we do have a great article that compares Supercharging and Re-Gearing… and you can read our full detailed review of the Magnuson Supercharger as well.

Now back to re-gearing…

Gears 101

If you have no clue what gears actually are or how they work, the easiest and most familiar way to understand gears is thinking about a road bike or a mountain bike.

The gears on a bicycle are the clusters of spiky circular rings around the pedals and at the rear wheel which the bike chain wraps around.

Gears are necessary for the process of transferring power from the power source down to the movable object (in this case, the bike wheels).

If you’ve ever ridden a road bike or mountain bike, you will know that its “easier” to accelerate and/or climb inclines when you switch the bike chain to the largest gears.  The larger gears are creating more torque since they are letting your legs turn higher RPMs at slower moving speeds when there is a lot of net force against you.

Conceptually speaking, gears in cars work just about the same way.

Why re-gear to 4.56 or 4.88?

I think it’s safe to assume that most of you reading this have already added weight and larger tires to your 4Runner.  If you haven’t already, you’re probably planning on doing so sooner rather than later!

A stock 5th Gen 4Runner’s power band was geared for a 4400 lb truck needing to turn 31” tires… It wasn’t geared for a 5800 lb truck turning 33”, 34”, or 35” tires.

A stock 5th Gen 4Runner is geared with 3.73 gears.

Proper re-gearing will reset your drivetrain to efficiently deliver the extra torque needed to the wheels on your heavier 4Runner with oversized tires.  Re-gearing allows your engine to work a little easier and efficiently turning those wheels especially during acceleration or while under load.

Long term, re-gearing should reduce the amount of stress on the drivetrain and hopefully prevent extra wear, tear, and breakage on heavier modified 4Runners.

Also, if you own a 4Runner and you are a bit of a speed junkie, I will say I cannot help you. You may have bought the wrong vehicle, to begin with… 🙂

However, the fact is, re-gearing will absolutely improve your truck’s acceleration and zippy-ness.

But you have a supercharger, why did YOU re-gear?

Fair question and there are a few reasons…

First and foremost, I’m self-admittedly a bit of a speed junkie.

Coming from a previous 5.7L V8 daily driver, the 4Runner wasn’t just a step down in power and acceleration, it was practically a fall off a cliff.  I decided early on I wanted to do all the major upgrades to retain a much power and acceleration possible on the 5th Gen 4Runner.

Practically speaking, there are a few other reasons I decided to re-gear:

1. Low current mileage – at only 30k miles, both, my drivetrain and I,  are going to enjoy this investment for a verrry long time.
2. Tire size – I’m on 33” tires, and will likely upgrade to 34” tires next time I need a set.
3. More weight coming soon – Metal bumper, sliders, and winch are going to be my next mods
4. Load Weight – I carry a lot of extra weight when camping… for example, I move a family of 5, I carry an extra 8 gallons of premium gas for the Magnuson, onboard refrigerator, enough supplies for a family of 5, etc. It all adds up very very quickly to approximately a 6000lb curb weight.
5. Other’s Experience – Every single person that’s re-geared has said how much they love it.

Why I Chose East Coast Gear Supply

I choose East Coat Gear Supply due to convenience and reputation.

With East Coast Gear supply, you actually buy a pair of Assembled 3rd members with the gear size of your choice.  Additional options for the Toyota e-locker are available.

If you don’t have the stock Toyota e-locker, then that’s fine.

You can pay extra to have ECGS add an aftermarket e-locker or air locker of your choice.  You always have the option to just go with no lockers as well.

I found it a lot easier to call and place my order with an ECGS rep over the phone.

Lead times are 3-5 weeks, so you want to make sure you get your order 100% correct the first time and I found that placing an order on the phone was super easy and quick.

ECGS Sales Reps are extremely kind and knowledgeable and the whole process took about 5 minutes.

Once the order is ready-ready, ECGS ships you a pair of 3rd Members.

After your installation is complete, you ship back your old 3rd members to ECGS.  There is a core charge which is refunded once ECGS receive your old 3rd members safe and sound.

What happens after re-gearing?

Practically speaking, the most observable differences you will experience after a re-gear are exactly what you’d imagine.

Improved acceleration, improved fuel economy (especially “city mpg”), and your shifting points should feel normal again as if you were driving a stock 4400lb 4Runner right off the lot.

You will certainly notice higher RPMs, especially at cruising speeds. 

After switching to 4.56s,  I cruise at 70mph and doing about 2400RPMs on 33” tires.  BEFORE switching to 4.56s,  I was doing 70mph at about 2000 RPMs also on 33” tires.

The higher RPMs are due to your driveshaft having to make more actual turns to rotate your tire one full rotation.

On 4.56s the wheels turn “easier” but it takes almost one full extra rotation of the driveshaft to actually turn the tires 1 full rotation compared to the stock 3.73 gears.

Non-observable differences are mainly that your engine isn’t working quite as hard to turn the wheels in most circumstances.

Off-Road Performance after Re-Gearing

This is one area where re-gearing really shines!

When on the trail, your 4.56 gears are going to give you a great improvement in performance.

The 4.56s create a better crawl ratio which in Layman’s terms essentially means the added torque of your new gears translates into traversing obstacles more slowly and with more control.

With 4.56 gears, your engine can now rev higher keeping its power up even while at slower speeds which means you ought to experience way more throttle control off-roading.

When you do apply gas, your truck won’t immediately jerks forward (at least not very far) and the new gears will reduce any lurching you may have experienced in the past while trying to get over obstacles.

Hill descents will be a bit slower and controlled when holding it in 1st gear as well.

Let’s review the Pros & Cons…

Pros of Re-Gearing:

• Better Off-Road Control and Performance
• Quicker overall Acceleration
• Shifting Points return to normal
• The truck will feel lighter/faster
• Better Crawl Ratio on trails
• Likely improvement in Fuel Economy
• No more searching for gears
• Less Stress on the Drivetrain long-term

Cons of Re-Gearing:

• Higher RPMs at cruising speeds on 33” Tires
• Expensive Modification
• Equally expensive to reverse the mod

It’s been 3000 miles… so was it worth the cost?

Depending on what labor rate you get for installation, the full job using ECGS 3rd members probably will cost around $2300-$2800 (without having ECGS add lockers) with an experienced shop that knows what they are doing.

After 3000 miles of use, I will say that the re-gear has absolutely been worth it.  It is a pretty expensive modification…

Comparable in price with a good quality full-suspension upgrade, however, a re-gear is only about 1/3 of the price of the Magnuson Supercharger option.

For me, my truck’s low mileage was a big factor when considering investing a re-gear upgrade.

At just about 30k miles on the odometer, I will be able to enjoy the investment of this 4.56 gear upgrade for a very very long time to come, perhaps 250k or more miles on this vehicle!

Performance-wise, acceleration is better and the truck feels lighter!

You will absolutely notice the improvement in acceleration after the re-gear.

My 4Runner sits on 285/70/17 tires, full skid package, full-size Frontrunner Roof Rack, about a 2.5” lift… and the truck feels lighter and zippier than ever.

Granted I do have the Magnuson Supercharger installed, but the truck feels even lighter and it is faster even after the re-gear.

Regarding fuel economy, I happened to add a full RCI aluminum skid package to the underside at the same time that I re-geared so more added weight.

I also do a lot of highway miles at 70-75mph which is where you see the fuel economy gains of the 4.56s hit diminishing returns.

So for me, my fuel economy for me after 3000 miles actually didn’t actually change very much. It’s important to note that your experience with fuel economy will vary based on the specs of your rig and your driving habits.

The Magnuson Supercharger also takes a little bit of a hit on my fuel economy since the PSI boost is now almost always kicked-in, even at highway speeds due to the higher RPMs.

For those interested, with the Magnuson, 285s (approx 33”) tires, full Front Runner roof rack, RCI Skids, and 4.56 gears, my dash computer reads out 13.4mpg after 3k miles with the 4.56s.

I reset the MPG reading the day I got the 4.56s installed, so this is a 3000 mile reading with one 2-day off-roading trip in the midst of that 3000 miles.

90% of my driving or more has been highway mileage between 65-75mph.

The Verdict on RPMs

[LEFT: Stock 3.73 Gears, 1600 RPMs at 60mph, RIGHT: 4.56 Gears, 2000 RPMs at 60mph]

When cruising on the highways, the engine is usually turning about 2400-2600 RPMs…

At 60mph, the engine turns about 2000 RPMs. At 70mph, it turns about 2400RPMs at 75mph; it’s a bit closer to 2500 RPMs depending on wind and incline.

I knew the RPMs would be higher, but in real life, the “feel” of constantly higher RPMs was a bit of a shocker and took some getting used to.

With stock gears and the Magnuson SC, my cruising RPMs used to sit between 1900-2000 at 70-75mph.

However, cruising at 2400-3000 RPMs is really not stressing anything out even though you may not be used to it mentally.

Final Thoughts & Overview

One of the final reasons I decided to re-gear had to do with the possibility of increasing my tire size from 33” to 34” tires.

Making that tire size increase again adds to the amount of torque needed for the truck to operate efficiently and properly. And the 4.56 gears are capable of keeping that powertrain right where it needs to be with tires up to 34” in size.

I will be adding more weight soon too via metal bumper, winch, and rock sliders.

Some research indicates that 4.56 gears are even good-to-go for tire sizes all the way up to 35.”

There is a little bit of relativity because vehicle mass should also be accounted for too.  A very heavy 4Runner on 35” tires may be better off with 4.88 gears, but for the most part the overall consensus is that 4.56 gears are the proper for “built-out” 4Runners with tire sizes of 33” to 35”

All in all, I’m happy with this modification and would recommend it for anyone that wants to restore the balance of your power band and alleviate the sluggishness of a heavy 4Runner on oversized tires.