Toyota 3.4L TT recall

Must be sand in the block from the mould? If they still use that technique.

 

Ahh damn I need that rate

 

Giving them an old 3.5 V6 engine which runs forever.

 

I am not a real mechanic and never will be, but the front crankshaft bearing is located at the front edge of the engine contained between two aluminum castings. Most crankshaft bearings I have seen are contained within the block behind some form of a cover, which, it seems, provides for better oil circulation. I am not sure how much the expansion and contraction of the two-part aluminum castings have on bearing pressure, but combined with the limited oil circulation, could that be a problem?

If so, the new 2.4 looks like it has the same design.

 

This isn't too difficult to understand, it's not the motor, it's the manufacturing process that left debris in it. I'm sure toyota isn't putting some pos motor in their vehicles.

 

why is this in the 6th gen section? it should be in the "other vehicle" section or a stretch if you want to put it into the "4runner general" section, but thats just my opinion.

 

Can the OP correct the title as Toyota 3.4L Turbo engine recall

 

That’s an excuse by Toyota. Do you actually think they have been leaving debris in the engine blocks for three years now?

 

Yes, it happened on a limited basis and they finally figured out the cause. Toyota over engineers their motors to death.

 

The pictures of torn down motors that I've seen are bearing issues, not material in the engine issues.

 

Hyundai and Kia had the same explanation for their junk Theta II GDI engines and the issues persisted well beyond something a manufacturing change would have been able to fix. Admittedly they technically improved over their roughly-a-decade production run but hardly in a confidence inspiring manner.

I think what to look forward to is whether the 3.4L failures continue or drop off.

 

They came out with the debris excuse last year and tried to blame it on a bad employee. Now they have 2024 model year engines that have the same problems. It’s a BS story.

 

So they claim.. lol it’s evidently a POS motor in all new tundras

 

Incorrect

 

Says a Toyota fan boy.. I think the contrarian viewpoint is just as valid

 

Isn’t having to recall 100K engines pretty much the definition of a POS engine? If this was a Kia or Hyundai we certainly would be calling it a POS.

 

Not only Toyota, Lexus joined the party too even though it's built in Japan.
Tundra started with Turbo waste gate problems then both Tundra and LX600 with main baring issues. Pretty sure Sequoia and GX550 be next with the same engine.

I won't be surprised the Land Cruiser and 6G 4runner join with 2.4Turbo.

 

Those god damn idiot monkeys can’t figure out how to not make the driver side cv rumble and grind, inside the front diff… for like 30 years now…

 

you people are funny, bash toyota but when the domestics do it the same or worse, you dont even bat an eye since its the norm

overall in a general sense, i have better chances with a toyota than any domestic from my historical perspective since owning toyota's from 1981.

 

Not quite, the recall spans a large number but whether it actually affects them all is the question.

Honda has had a sizable recall for the 3.5L crankshaft that spans a large number of vehicles (250k) but currently a small number of affected engines is expected/estimated (1%, 2,500) and since the V6 has been, and continued to be considered dependable I don’t have reason at this time to doubt that estimate.

Hyundai/Kia has both the big recall counts and failures that I bet dwarfs both here.

 

So, this doesn't really have an impact on bearing lubrication - they are not oiled by splashing around them, there is typically and oil passage cut into one side of the bearing cap to provide flow from the oil passages.

Searching around for a good image to illustrate this I found this diagram. You can see the oil passage in the block that lines up with the oiling hole and groove in the top half of the bearing insert. Every main bearing journal in the block would have one of these passages, regardless of design.





The image above shows the traditional American V8 style of main bearing construction with individual main bearing caps (2 bolt mains in this drawing). As you noted a LOT of modern engines now have a cast split block with all the lower bearing retainers contained in a single piece casting which bolts onto the bottom of the block before the oil pan. It doesn't change how the bearings are lubricated.


I also found on the Tundra forum photos of a blown 3.4 opened up to work on the bearings. Its a 4 main bearing crank (typical for a v6), and shown here sitting in the lower split casting. Interesting here it appears to have discreet 4 bolt cast iron main bearing caps that the aluminum lower split block was cast around, fusing the caps and block into a single piece - very strong.

What you can't see in this photo are the oiling grooves that would be in the top half of the bearing journals in the main block.

 

I have seen many similar failures in racing. This looks like something affects oil pressure, as it look like oiling issue on that bearing. If you look, the rest of them appear to be fine. Someone suggested that it might be crankshaft flexing, but I think something like that would unlikely to make it past abuse testing. Plus, it is I4, so crank is simplest design of any configuration.

 

That would jive with the published Toyota explanation. If there where machining debris that dint get flushed out of those oil passages in the block it could have caused a blockage preventing flow to the bearings which would guarantee a catastrophic failure.

If so and if its a production/QC lapse that can be corrected going forward it may not be any fundamental flaw in the design.

 

These motors have been seizing up for 3 years. If the problem truly is machining debris and Toyota hasn’t started cleaning the debris out of the engine blocks better in the third year of that engine then Toyota has some serious issues going on. That’s worse than an engine design flaw to me.

 

While possible, it is extremely unlikely. These are small metal shavings, how would you get enough of them to plug an oil passage?

 

Correct

 

each brands has very different luck with their turbo gas engines. With Ford, the 3.5 EB is chronically problematic but their 2.3 4 cylinder used in the ranger and Bronco is surprisingly trouble free.

 

"You keep using that word, I do not think it means what you think it means". The 2.3L hasn't been trouble-free.

https://static.nhtsa.gov/odi/tsbs/2023/MC-10233849-0001.pdf

 

In the grand scheme of things it is considering the small number of vehicles involved.

Certainly doing better than the Toyota turbo engines.