2 Easy-To-Fix Transmission Problems Of A Toyota 4Runner

According to iSeeCars.com and their 2019 study, the Toyota 4Runner is the 5th longest-lasting vehicle in the US. A whopping 3.9% of all 4Runners had more than 200,000 miles. In this blog, we are looking at all the transmission problems of the 4Runner in the past 20 years. Here is a quick summary of our findings:

Both the 4-speed and the 5-speed automatic transmissions in the 4th and 5th generation 4Runner are highly reliable. The most common problem is shift solenoid failure at high mileage (250,000 miles +).

If you are after the entire story, make sure you sit tight. As we continue, we look at all the owners’ complaints, technical service bulletins, and potential recalls that address the transmission. Keep reading!

Also, read our full article, in which we explain the most common problems of the current generation 4Runner.

Common Toyota 4Runner Transmission Problems

We will take a closer look at the fourth and fifth-generation Toyota 4Runner and first list the available transmissions in each generation. We will then present our findings for each of the transmissions.

Fifth Generation – N280 (2010 – Present)

The fifth generation was, in some sense, a disappointment to many. The fact that it did not carry on the 4.7L V8 from the previous generation was “devastating”. Nonetheless, the N280 generation still features the 4.0L V6 and featured the 2.7L l4 in its first year of production. Enough about the engines; here are the available transmissions:

• 4-speed automatic A340E/F (2.7 L)
• 5-speed automatic A750E/F (4.0 L)

The 4-speed automatic transmission was only available in 2010, together with the 2.7L 4-cylinder engine. Both were discontinued in the 2011 model year 4Runner. The 5-speed automatic came in two variants: the A750F for the 4WD model and the A750E for the 2WD model. 

Both 5-speed transmissions are mechanically identical. However, the A750F does allow for the attachment of the 4WD transfer case. Let’s get to the problems.

5-Speed Automatic

The truth about this transmission, which can be found in the 4Runner today, is that it is a transmission from 2003. It was first released for the 2003 model year 4Runner and has stayed the same since then. 

For some reason, Toyota decided to keep this seemingly “ancient” transmission in the 4Runner, but at the same time, they have been introducing more modern 8-speed and CVT transmissions in other models.

This transmission is a bit older and tried and tested, which makes for excellent reliability. That is also why there are very few NHTSA owners’ complaints regarding this transmission.

Two problems seem to be common and unrelated to high mileage or excessive abuse. The first problem is related to the neutral safety switch prone to water damage.

Due to poor design, water can enter and damage the neutral safety switch in the 4Runner. This prevents the car from shifting into Park or shifting out of Park; it can also light up the 4Lo light, it can bring up specific diagnostic trouble codes, and so on.

It is relatively easy to fix, so Toyota never took it too seriously and fixed the problem.

The second problem that we detected was shuddering. This mainly happens because of contaminated transmission fluid that eventually causes havoc on the valve body. Not only can this lead to shuddering, but it can also lead to delayed engagement, overheating, and premature wear of certain internal parts.

Many people faced this problem because Toyota considered the A750 series transmission a closed unit. Meaning it does not need fluid replacement. The truth is the A750 needs a fluid replacement every 30,000 – 60,000 miles.

Learn more about this problem in this lengthy owner’s thread.

If you buy a 4Runner with this transmission, make sure it receives regular fluid changes. It is the only thing that this transmission asks for. If you do the bare minimum, this standard automatic should outlast your engine with ease.

4-Speed Automatic

The 4-Speed automatic was only featured in the 2010 model year of the 5th generation 4Runner. During this time, there were no NHTSA owners’ complaints, technical service bulletins, or recalls regarding this transmission.

Much like the 5-speed transmission we just discussed, this transmission is “old-tech”. It has been tried and tested through many model years of the previous generation 4Runners, so it should not be causing any trouble if maintained right.

Fourth Generation – N210 (2003 – 2009)

The fourth generation drove the 4Runner philosophy forward, and with all the design and chassis changes, it was an instant hit. Toyota released the 4th generation 4Runner with the following transmissions:

• 4-speed A340E/F automatic
• 5-speed A750E/F automatic

We have already revealed all the A750 transmission problems before. The A750 Aisin Warner transmission revealed with the 2003 model year 4Runner has remained the same to this day. 

4-Speed A340E/F Automatic

If you want to know everything about this transmission, just check this owner’s thread. Yes, 300,000 miles with regular maintenance is nothing out of the ordinary for these transmissions.

The only thing that is prone to going bad at high mileage is the shift solenoids. The transmission can start shuddering, hesitating, and acting erratically as they fail. This typically happens after the 200,000-mile mark.

Without extreme abuse and with regular maintenance, these transmissions are quite literally top-tier in terms of reliability. Owners that use these transmissions for heavy towing often install an external transmission cooler and aftermarket filter and ensure the transmission fluid gets replaced every 30,000 – 40,000 miles.

5-Speed A750E/F Automatic

We already covered the ins and outs of this transmission when we talked about the fifth-generation 4Runner. It is the same transmission, and Toyota has never had to address any problems with TSBs or recalls.

All the TSBs that address these transmissions are meant for service technicians and provide nothing that would contribute to this blog.

If you are in the market for a 4th generation 4Runner with this transmission, make sure it has clear maintenance history.

Other Problems Related To The Powertrain

The transmission is not the only part of the drivetrain. To paint a whole picture, we also want to point out 5 TSBs that are related to the drivetrain:

•  Toyota TSB T-SB-0026-15
  
  This technical service bulletin addressed the cyclic groaning or grinding noise coming from the front differential. This affected Toyota 4Runner vehicles with part-time 4WD made from 2004-2017. The noise can be eliminated by replacing the needle bearing on the left side of the front differential.
  
• Toyota TSB T-TT-0334-15
  
  Certain 2013-2015 4Runners were prone to developing a leak from the input shaft seal on the transfer case assembly. This TSB provides photos of the locations of the leak and where the leaked fluid ends up accumulating.
  
• Toyota TSB T-SB-0040-12
  
  This TSB addressed the clunking noise from the rear of the vehicles. Certain owners also described the sensation as receiving a bump from behind just before coming to a stop or when accelerating from a stop.
  
  This TSB provides a repair procedure that resolved the problem on the rear driveshaft.
  
• Toyota TSB T-SB-0079-21
  
  Some 2019-2020 model year 4Runner’s may have grease leaking from the inboard joint boot edge where the clamp sits on the front drive shaft. Vehicles with fewer than 25,000 miles on them and no obvious damage to the boot may develop this condition.
  
  This TSB provides a repair procedure to resolve this issue.

• Toyota TSB T-SB-0175-10
  
  This TSB addressed the growling/rumbling noise coming from the front differential assembly on the 2010 model year 4Runner. This condition was only noticeable when driving in 2WD mode. This TSB provides the repair procedure to resolve this issue.
  

If you are ever in the market for a second-hand Toyota 4Runner, make sure there is no weird noises or vibration when driving in 4WD mode. There should also be no problem or hesitation when shifting from 2WD/4WD. 

Have the vehicle inspected by a professional if you are not comfortable evaluating the state of the vehicle on your own.

How Much Does A Toyota 4Runner Transmission Cost?

• 5-Speed A750E/F Rebuild Kit: 250$ – 500$ (eBay)
• 4-Speed A340E/F Rebuild Kit: 200$ – 300$ (eBay)
• Remanufactured A750E/F or A340E/F: 2000$ – 2500$ (SPPrecision)
• Refurbished valve bodies (both transmissions: 175$ – 350$ (eBay)
   

How Long Does A Toyota 4Runner Transmission Last?

Both of the transmissions we mentioned in this article are absolute powerhouses in terms of reliability. Both the 4-speed A340E/F and the 5-speed A750E/F will easily last 300,000 miles and more with regular maintenance

Closing Thoughts

In wrapping up, it’s critical to acknowledge how understanding the common problems of the current generation Toyota 4Runner can greatly enrich your experience as an owner.

Being tuned into these issues allows you to effectively troubleshoot or even prevent some hiccups down the road. As an informed owner, you’re all set to make the best decisions to keep your 4Runner in top shape. That includes understanding everything from fuel options to common problems and everything in between.

Stay ahead of the curve, and enjoy the ride!