2025 Engine Problems

[purplenova]

Brother in law is looking at the new 2025. Are there engine issues like the Tundra was experiencing?

 

[Jeff_DML]

Nothing I have seen yet

Edit: I personally would just get the 2.4T gas engine and not the hybrid setup to minimize complexity for reliability

 

[88Center]

Brother in law is looking at the new 2025. Are there engine issues like the Tundra was experiencing?

New 4Runner has same engine as 2024+ Tacoma and 2025 Land Cruiser. Toyota worked out most of the problems on the Tacoma, which came out more than a year before the new 4Runner and Land Cruiser. Taco owners were the guinea pigs.
Tundra has a V6.
4Runner has a 4 banger.

Tundra made in US.
4Runner made in Japan.

Tundra probably not the best comparison.

 

[5thToy]

New 4Runner has same engine as 2024+ Tacoma and 2025 Land Cruiser. Toyota worked out most of the problems on the Tacoma, which came out more than a year before the new 4Runner and Land Cruiser. Taco owners were the guinea pigs.
Tundra has a V6.
4Runner has a 4 banger.

Tundra made in US.
4Runner made in Japan.

Tundra probably not the best comparison.

T24 was also used in the Lexus NX/RX and Highlander prior to that.

 

[thatoneguy]

T24 was also used in the Lexus NX/RX and Highlander prior to that.

Yep, this engine has been around for 5+ years now in one form or another. So far it has proven pretty stout in all applications. It is reasonably overbuilt, smart for such a widespread corporate engine. I wouldn't fear this powerplant at all.

 

[88Center]

the livability office is coming after me ...

Neighborhood gestapo?

Sounds like one of your neighbors called someone and complained. That sucks. Hopefully you get it all fixed up soon.

I need to do my cv axels. Either new boots or refurbished ones. Either way, it's going to be a lot of work.

 

[02SE]

Engine problems? What do you know about engine problems?

when my 1999 Toyota 4Runner hit 265K miles this year, it began shitting the driveway.

So far this year i've spent $2500 on parts and tools.

New cylinder heads, new head gaskets, new timing belt, new water pump, new thermostat, new spark plugs, new valve cover gaskets, new heater control valve, new pcv valve, new radiator, new transmission filter, new starter, new rear axle bearing, new rear axle seal, new rear suspension coils, new battery, new transmission oil dipstick,

One thing after another. What will fail on my 4runner today? Stay tuned.

I still need to install new shift knob bushings, new actuator for passenger door, replace emergency brakes, figure out why cruise control won't set, figure out why ABS activates too often when it shouldn't, figure out why some LEDs don't come on in the dash,

The nice thing is that the replacement parts are readily available and fairly unexpensive compared to other vehicles. Also the knowledge base of this community and guys like Tim the Toolman doing videos how to fix everything is a huge silver lining in all of this.

Also when i was replacing the starter through the passenger front wheel well i noticed grease leaking out of the ball joints so now i have to order upper and lower ball joints, new sway bar link, maybe even a new cv axle.

I've worked on my 4runner so much the last 6 months that the livability office is coming after me for having an "inoperable vehicle" in my driveway since on any normal day the hood is up. The vehicle runs and is operable but my neighbors must think i started a 4runner salvage yard.

So after 26 years and nearly 300k of apparent maintenance neglect, all that deferred maintenance is coming due.

You may recall the old advertisement: "You can pay me now, or pay me later"

As for the 2025 6th gen 4Runner engine, it's long-term reliability is still unknown. The biggest problem I have is the glaringly obvious cost-cutting, and readily apparent chintzy build quality.

I guess we'll see if Toyota addresses some of those issues, as the 6th gen 4Runner matures.

 

[Sense-A]

haha yeah but i'm beginning to wonder how much of the original vehicle i will have left after i replace everything. LOL

Are you the kind of guy that likes to keep trading in for newer vehicles? Or do you grow attachment to a vehicle and try to keep it running as long as possible?

You're probably the guy always interested in the new model. That's cool. Different personality. I'm the kind of guy that just wants to get familiar with my truck to keep it running forever and learn as much as i can about it and not worry about new models.

I always first attempt to repair things before seeking to buy a new item or replacement.

I don't like the direction vehicle makers went with newer cars post 2000. I love 1960s American muscle cars.

 

[Black Canyon]

2025 4Runner Transmission Overheating on Climbs Off-Road

Not the engine, but the transmission - our 2025 6G OR Hybrid transmission overheats on slow offroad climbs. Took it the dealer and turns out to be a software issue, as expected. They made a Technical Assistance Case (TAS) with Toyota (first in the national apparently) as Toyota has no fix yet for this.

 

[Jeff_DML]

Not the engine, but the transmission - our 2025 6G OR Hybrid transmission overheats on slow offroad climbs. Took it the dealer and turns out to be a software issue, as expected. They made a Technical Assistance Case (TAS) with Toyota (first in the national apparently) as Toyota has no fix yet for this.

hmm, seems odd they determined it was a SW issue but no fix. 5th gen can overheat if you are in 4H, running in 4l helps.

 

[02SE]

haha yeah but i'm beginning to wonder how much of the original vehicle i will have left after i replace everything. LOL

Are you the kind of guy that likes to keep trading in for newer vehicles? Or do you grow attachment to a vehicle and try to keep it running as long as possible?

You're probably the guy always interested in the new model. That's cool. Different personality. I'm the kind of guy that just wants to get familiar with my truck to keep it running forever and learn as much as i can about it and not worry about new models.

I always first attempt to repair things before seeking to buy a new item or replacement.

I don't like the direction vehicle makers went with newer cars post 2000. I love 1960s American muscle cars.

You know what happens when you 'assume'...

Anyway I'm a former Master Tech. First at a Toyota dealership, then independent shops which worked on all makes.

I had a 3rd gen 4Runner from new for 22+ years.

What I'm saying is that your description of your 4Runner indicates it was maintenance neglected. Most vehicles on the road are. Vehicles will also eventually wear out, that will happen more quickly if maintenance is neglected.

I sold my unicorn 3rd gen for a ridiculous amount of money, to a guy who recognized it for what it was. With the proceeds I bought a 5th gen TRD ORP. It's a nicer vehicle to drive all around.

I appreciate older classic cars. My first car was a 1970 Duster 340 W/4-speed. I rebuilt the engine and transmission for it to become my first car at 16. I wish I hadn't sold it to buy a 4wd truck back in the day...

The point of all this is to say you have an old vehicle, which was neglected. If your 4Runner had been properly maintained, the wholesale parts replacement list would be shorter.

I have a bunch of vehicles as they are my hobby. Some older, some newer, but all bought because they offer unique experiences. They are all well-maintained.

 

[02SE]

Not the engine, but the transmission - our 2025 6G OR Hybrid transmission overheats on slow offroad climbs. Took it the dealer and turns out to be a software issue, as expected. They made a Technical Assistance Case (TAS) with Toyota (first in the national apparently) as Toyota has no fix yet for this.

For a slow off-road climb, you should be in low-range in any 4wd vehicle. This increases the mechanical advantage due to the lower gearing, and won't heat up the transmission nearly as readily as trying to climb slow, steep roads in high-range.

This is also the reason soft-roaders like Subarus are banned on some 4wd trails. The owners think they can go anywhere in their Subaru, but quickly overheat the transmission, and then they require being recovered from the trail.

Bottom line: If you aren't in 4lo during those slow off-road climbs, it's driver error. If you are in 4lo and are still overheating, then there might indeed be an issue with Toyota's engineering on the 6th gen.

 

[Jeff_DML]

For a slow off-road climb, you should be in low-range in any 4wd vehicle. This increases the mechanical advantage due to the lower gearing, and won't heat up the transmission nearly as readily as trying to climb slow, steep roads in high-range.

This is also the reason soft-roaders like Subarus are banned on some 4wd trails. The owners think they can go anywhere in their Subaru, but quickly overheat the transmission, and then they require being recovered from the trail.

Bottom line: If you aren't in 4lo during those slow off-road climbs, it's driver error. If you are in 4lo and are still overheating, then there might indeed be an issue with Toyota's engineering on the 6th gen.

yep:thumb3:

btw, where are subaru's(AWD) banned?

 

[02SE]

yep:thumb3:

btw, where are subaru's(AWD) banned?

The National Park Service will cite drivers of AWD soft-roaders if they drive onto 4wd trails. Googling will bring up plenty of info on the topic.

I've seen signs warning against the AWD mall crawlers venturing onto 4wd trails at their own risk, and they will be responsible for the cost of recovery, in other non-National Park locales.

 

[Buffaloe]

Brother in law is looking at the new 2025. Are there engine issues like the Tundra was experiencing?

My wife has 2025 Sequioa hybrid and it is great with no problems. Passing push is great when you need it. Drive it in the mountains btw.

Fan of the hybrid ISOMAX

 

[Hadelson]

For a slow off-road climb, you should be in low-range in any 4wd vehicle. This increases the mechanical advantage due to the lower gearing, and won't heat up the transmission nearly as readily as trying to climb slow, steep roads in high-range.

This is also the reason soft-roaders like Subarus are banned on some 4wd trails. The owners think they can go anywhere in their Subaru, but quickly overheat the transmission, and then they require being recovered from the trail.

Bottom line: If you aren't in 4lo during those slow off-road climbs, it's driver error. If you are in 4lo and are still overheating, then there might indeed be an issue with Toyota's engineering on the 6th gen.

Do not agree with this. Have a 24 Taco Trailhunter. One of my hunting areas has a dirt road were you gain 500 feet over 3 miles. You can drive it in two wheel drive........put in 4Hi and it over heats. This is a software and design issue. 4Lo no issues-but absolutely not needed for this road. Go over to the Taco forum-owners are having issues with towing trailers and just backing into there driveways. Last T4R was a 17 Pro. It was a off-road beast and never had anytype of cooling issue

 

[02SE]

Do not agree with this. Have a 24 Taco Trailhunter. One of my hunting areas has a dirt road were you gain 500 feet over 3 miles. You can drive it in two wheel drive........put in 4Hi and it over heats. This is a software and design issue. 4Lo no issues-but absolutely not needed for this road. Go over to the Taco forum-owners are having issues with towing trailers and just backing into there driveways. Last T4R was a 17 Pro. It was a off-road beast and never had anytype of cooling issue

The comment I replied to stated "slow, off road climbs". With no specifics as to what exactly constitutes "Slow, off road climbs". To me, a "slow,off road climb" would mean I've shifted into 4lo, greatly increasing mechanical advantage, and lowering the possibility of overheating the drivetrain.

Your situation is not what I would a consider a "slow, off road climb".

If Toyota's cost-cutting has extended to inadequate cooling of the new Tacoma and 4Runner drivetrain, well, that's yet another reason why I haven't sold my low-mileage 5th gen TRD ORP, and bought a new 6th gen 4Runner.

 

[Hadelson]

The comment I replied to stated "slow, off road climbs". With no specifics as to what exactly constitutes "Slow, off road climbs". To me, a "slow,off road climb" would mean I've shifted into 4lo, greatly increasing mechanical advantage, and lowering the possibility of overheating the drivetrain.

Your situation is not what I would a consider a "slow, off road climb".

If Toyota's cost-cutting has extended to inadequate cooling of the new Tacoma and 4Runner drivetrain, well, that's yet another reason why I haven't sold my low-mileage 5th gen TRD ORP, and bought a new 6th gen 4Runner.

Let me spell this out in more detail. Run this road in 2-wheel drive and no issue. Place in 4HI and Trans temps creep up. To me and many others, this means the cooling system is inadequate to handle a simple dirt road in 4HI. Too many other examples as well where people backing trailers up steep driveways in 4HI receiving overheating warning.

 

[toyo]

For a slow off-road climb, you should be in low-range in any 4wd vehicle. This increases the mechanical advantage due to the lower gearing, and won't heat up the transmission nearly as readily as trying to climb slow, steep roads in high-range.

This is also the reason soft-roaders like Subarus are banned on some 4wd trails. The owners think they can go anywhere in their Subaru, but quickly overheat the transmission, and then they require being recovered from the trail.

Bottom line: If you aren't in 4lo during those slow off-road climbs, it's driver error. If you are in 4lo and are still overheating, then there might indeed be an issue with Toyota's engineering on the 6th gen.

Not to mention that the RPM's will be higher, hence the engine will be moving the coolant faster, ECM will demand the fan run faster as well, etc, etc.

 

[rdruss]

Based on what I've read so far about the new 4Runner I can see no reason for an existing 4Runner owner to "upgrade".