The Toyota 4Runner is a long-running mid-size SUV that has been in production since 1983.
In the Japanese market, it was known as the Hilux Surf and was produced from 1983 to 2009, but outside it continues to be popular where it is sold in North and South America.
It’s known as one of the most lasting SUVs in the world, achieving on average 200,000 miles or more.
This article answers why is “Toyota 4Runner 4 Wheel Drive (4WD) Not Working?”…
What Is 4WD?
“4WD” or “4-wheel drive” describes a type of drivetrain on a car in which torque from the engine is sent to all four wheels to move the vehicle, as opposed to just the front wheels on a FWD model, or the rear wheels on a RWD model.
It is a feature that was most commonly featured on SUV models but now is also popular on many sedans and even smaller cars for the greater traction and control that it gives, especially when off-roading or driving competitively.
How Does It Work?
A 4WD system works by the engine first sending power through the transmission, which then splits the power and sends it in equal measure to both the front and rear wheel axles.
Torque is then transferred to all 4 wheels to boost traction on the road.
It is essentially a system designed to increase traction and contact with the road surface, and thus optimize vehicles for off-road situations where two wheels may be stuck, so the other two can gain traction and pull the vehicle forward.
Do All 4Runners Come With 4WD?
No, not all Toyota 4Runners come with 4WD. Buyers have a choice whereby they can select a 2WD model, or 2WD with part-time 4WD, or full-time 4WD.
The presence of which system is typically dictated by the trim level of the particular 4Runner.
In the 2020 4Runner, for instance, the SR5 and TRD off-road models come with part-time 4WD with the Active Traction Control system built-in.
The Limited model has a full-time 4WD with the same A-TRAC system as well as a superior limited-slip center differential.
How To Know If My 4Runner Has 4WD?
If you want to know if your Toyota 4Runner has 4WD or not, you can inspect the manual, of course. But there’s another sign, as well.
Look where the gear shifter is, and see if there is one if there are two shifters.
In 4WD models, there was a second shifter there for the 4WD functions. Therefore, if you have the second shifter, you have 4WD in your 4Runner.
If you are driving a newer version, however (4th generation onwards) then you should see a switch for the 4WD on the central control stack.
Why Is My 4WD Not Working?
If you bought the 4Runner to use its 4WD function because of where you live or the winter climate or another reason, then it can be quite disconcerting when it breaks down.
The most common cause behind 4WD failure in the Toyota 4Runner is the ECU and/or the actuator seizing up. A seizing actuator is the most common problem.
First, let’s deal with the ECU. When the ECU fails to send a signal to the system, it won’t activate, even when you are shifting into 4WD using your shifter.
When you shift into 4WD, do you hear a clicking noise underneath? You should hear that click to indicate it is engaging. You should also see a dash light indicator.
When you see neither of these signs, the most likely culprit is the ECU or actuator not working.
It’s hard to DIY fixes on the ECU because it’s so specialized. To get a replacement can cost $900 with parts and labor, making it an expensive task.
It can even be as high as $1450 depending on your geographical location.
An independent mechanic would likely charge the lower estimate, whereas the dealership would charge the higher one.
If the actuator is the problem, it’s a cheaper fix at just $350 on average including parts and labor.
The reason for that is the actuator is a mechanical part and not as complex to repair or replace as the control modules.
It is, however, awkwardly located and harder to get at, which is why a DIY fix is unlikely.
One other possible cause is the vacuum control solenoid becoming faulty and needing a replacement.
This can be fixed for just $110-130 with parts and labor but can be trickier than it sounds to do.
With some know-how, you could fix this yourself, but it’s not recommended if you don’t have experience.
How To Prevent A 4WD From Failing?
The main method of preventing your 4WD from failing on the 4Runner is to use the 4WD regularly. What’s the advice of the Toyota 4Runner community? “Use it or lose it.”
At least once a month, you should cycle through your various 4WD options… 4WD HI, 4WD LO, 2WD, etc.
Use each one for a while. By cycling through the options and driving in each mode, you prevent the actuator from seizing up.
The actuator seizing is most often caused by inactivity and long periods of being in one drive mode and not cycling to others.
This is even more likely to happen in cold climates and/or when a cold winter arrives.
It doesn’t matter if you need to use them very often, you should use them just to keep them moving and active so that they won’t get locked up.
It is similar to the concept of driving your car to keep the battery charged.
When Should I Use 4WD And When I Shouldn’t?
You should 4WD when you feel you will benefit from additional traction on the road.
For example, you might use it in snowy, icy, or otherwise wintry conditions where it is easy for one or more wheels to lose traction.
With 4WD activated, it won’t matter as much if one or even two wheels lose traction because you’ll have two more actively working to maintain balance.
Another time 4WD is useful is when off-roading.
Transferring torque to all four wheels ensures greater ease of movement on uneven terrain, and similarly to the winter/snow conditions, if one or two tires become stuck, there are two more that can maintain traction and pull the vehicle forward.
You should cycle through the 4WD options at least once a month regardless of need, as well, just to prevent the actuator and any other cables/lines from seizing up.
This is especially important in the 4Runner 4WD system.
When you are driving on smooth, flat, and dry roads, you should turn off 4WD.
4WD naturally consumes more gasoline than 2WD so if you have the option, turn it off when driving on smooth, flat roads.
If your vehicle has permanent/full-time AWD, such as the Audi Quattro system, then there’s no turning that off and you just have to deal with lower efficiency.
Does Toyota Warranty Cover 4WD Failure?
The Toyota 4Runner comes with a 60-month or 60,000-mile warranty on the powertrain, as well as a 36-month and 36,000-mile basic warranty.
The former covers failures in the transmission when they are due to manufacturer error.
If the 4WD fails as a result of something connected to a manufacturer error and not anything on the part of the owner, then yes it should be covered by the warranty.
If Toyota were to determine that you had caused the 4WD failure most likely because of driving that went against the manual warnings/recommendations, or because you had not stuck to the recommended maintenance schedule, then it would not be covered.
What Models/Years Are More Prone To 4WD Failure?
The fact is that any model with 4WD contains the main vulnerability of the actuator possibly seizing up due to long periods of idleness.
That’s all generations, but especially the 4th generation and earlier.
The most serious 4WD failings tended to happen more on older models from 1996 to 2000.
This is where most customer complaints regarding the 4WD system could be found.
Toyota has since made improvements to the way the 4WD is activated and controlled and that has increased reliability on the latest-generation models.
Be mindful of 4th generation models and earlier.
Does The 4WD System Need Maintenance?
Toyota recommends that you get a scheduled service on your 4Runner every 5,000 miles or 6 months, whichever comes first. This service will include checks on the 4WD system.
The service typically checks the mechanics of your 4WD, but especially the actuator and cables to make sure nothing has seized up and/or stopped working.
A technician will check in the transfer case to make sure the actuator and connected components are all working.
Can Bad Use Of 4WD Damage The System?
Using 4WD when you’re on smooth, flat surfaces or at high speeds on the highway is bad for your car and can cause some damage.
This is because when you use 4WD on a road on which traction is already strong, you create stress on the drivetrain and will wear out the tires much faster.
The 4WD system is specially designed for those low-traction situations and low-speed situations where the wheels operating with their own power won’t affect the drivetrain too much.
When you try to do that on a high-traction surface, it does far more harm than good.