twin-turbo pickup truck issues?

[edyvw]

Fuel efficiency in turbo engines greatly depends on the manufacturer, meaning execution. Toyota spent the last two decades focusing on obsolete engines because that was the targeted customer group. However, emissions increased with them, and there is a learning curve here.
BMW, for example, does not have an issue getting in real-world driving 27-30 mpg in vehicles like the X7. Know-how matters, A LOT.

 

[KJSmith]

It has nothing to do with the turbos.

We Finally Know Why the Toyota Tundra V6 Keeps Self-Destructing

Owners have been demanding answers to their problems with main bearing failures. Now, Toyota is issuing a recall with an explanation.

www.yahoo.com

 

[The Lube Guy]

It has nothing to do with the turbos.

We Finally Know Why the Toyota Tundra V6 Keeps Self-Destructing

Owners have been demanding answers to their problems with main bearing failures. Now, Toyota is issuing a recall with an explanation.

www.yahoo.com

No, but neither is Toyota being honest. They pulled a page out of Hyundai's playbook to cover up bad engineering. When Hyundai got in trouble with the Theta II engines, they pulled the same excuse. Except, it wasn't debris killing the Theta II engines, and it isn't debris here either. It's just bad cost-saving engineering.

I looked at these before, and I'm so happy I didn't pull the trigger and bought one.

 

[irekm]

Fuel efficiency in turbo engines greatly depends on the manufacturer, meaning execution. Toyota spent the last two decades focusing on obsolete engines because that was the targeted customer group. However, emissions increased with them, and there is a learning curve here.
BMW, for example, does not have an issue getting in real-world driving 27-30 mpg in vehicles like the X7. Know-how matters, A LOT.

It is quite simple, efficient bigger engine and staying out of boost...

 

[edyvw]

It is quite simple, efficient bigger engine and staying out of boost...

It is really not “quite simple.” Otherwise, we would not be here discussing it.
New Sequoia with mild hybrid system barely can get 20mpg on hwy! When you are on hwy, you always have “boost.”

 

[Ronin73]

I have a 108 roundtrip hwy drive everyday and I am rarely, if ever, in boost on my Ford 3.5. I am killing it with mpg...usually 28-30. Love it.

 

[Burt]

But is it worse?

A gallon of gasoline has a fixed amount of energy in it. If a turbocharged small engine makes the same mpg doing the same work as a larger NA, then the efficiency is the same. The turbo engine might cost more to purchase, but get better mpg unloaded. No NA encylinders

But is it worse?

A gallon of gasoline has a fixed amount of energy in it. If a turbocharged small engine makes the same mpg doing the same work as a larger NA, then the efficiency is the same. The turbo engine might cost more to purchase, but get better mpg unloaded. No NA engine ever lost a turbo, but they suffer at altitude.

A turbo charged engine needs fewer cylinders/displacement so it has less internal friction and weight for a given hp. This benefit tends to be offset as the boost increases and higher compression requires ignition retardation. So relatively better hp/fuel ratio at low load, not so good at high loads.

 

[edyvw]

I have a 108 roundtrip hwy drive everyday and I am rarely, if ever, in boost on my Ford 3.5. I am killing it with mpg...usually 28-30. Love it.

You are in boost. Turbo aways works. Peak torque in Ecoboost is at 2,500rpms, 90% available at 1,700rpms.
Engine just runs in its optimal range. That is it.

 

[Ronin73]

You are in boost. Turbo aways works. Peak torque in Ecoboost is at 2,500rpms, 90% available at 1,700rpms.
Engine just runs in its optimal range. That is it.

I have the boost screen in my dash that shows when it is being used. As I stated, it rarely moves…when I get on it, of course, or take off quickly, but cruising, nope. I am lot in boost.

 

[irekm]

It is really not “quite simple.” Otherwise, we would not be here discussing it.
New Sequoia with mild hybrid system barely can get 20mpg on hwy! When you are on hwy, you always have “boost.”

That's weird, 2 of my boosted cars on the hwy for majority of the time run in vacuum. What cars run under boost on the hwy? I assume it is fairly flat road and speeds lets say up to 80mph

 

[hemioiler]

You are in boost. Turbo aways works. Peak torque in Ecoboost is at 2,500rpms, 90% available at 1,700rpms.
Engine just runs in its optimal range. That is it.

Those specs are at WOT. That's important, if you're just feathering the pedal and sitting at 1700 rpms you're not at 90% peak torque.

As he said, the boost gauge will tell you how hard the engine is working at those rpms. It can be anywhere from loafing to full out WOT.

 

[irekm]

Exactly

 

[edyvw]

That's weird, 2 of my boosted cars on the hwy for majority of the time run in vacuum. What cars run under boost on the hwy? I assume it is fairly flat road and speeds lets say up to 80mph

I would say you must have boost, how much depends on vehicle etc.

Those specs are at WOT. That's important, if you're just feathering the pedal and sitting at 1700 rpms you're not at 90% peak torque.

As he said, the boost gauge will tell you how hard the engine is working at those rpms. It can be anywhere from loafing to full out WOT.

sure, boost is not binary, you have it or don’t. But you are always there.

 

[irekm]

Well then, ecu must somehow be sending wrong info to OBD II port, I get the info from there when it comes to my engine parameters.

As the gentelman before said, engine will stay in vacuum unless you need boost, I'am sure on the straight road I can get to 75mph never hitting any psi. It will be painfull process though

 

[supton]

A turbo charged engine needs fewer cylinders/displacement so it has less internal friction and weight for a given hp. This benefit tends to be offset as the boost increases and higher compression requires ignition retardation. So relatively better hp/fuel ratio at low load, not so good at high loads.

True, but I recall a number of owners indicating better mpg with 91 octane, presumably due to not needing to pull timing. So if you ignore the extra cost of premium, a turbo does not have to pull timing--and of course, a low pressure turbo might never hit the high cylinder pressures (but true, might not be a small displacement engine in the first place).

Now if they are running rich to keep cool and prevent melting pistons (apart from detonation), well that's a killjoy for sure.

 

[BrianF]

While not a 1/2 ton engine, the 6.7 in my 3500 has been chugging along just fine for 160,000km. It loafs along down the highway unloaded with barely any boost but lights up in a hurry.

The only reported issues with whatever Holset unit is used, the electronic actuators are apparently garbage. Likely garbage coolant seals leaking and frying the electronics. While no consolation prize, at least its not the variable vanes or bearings burning out.

 

[Pew]

That's weird, 2 of my boosted cars on the hwy for majority of the time run in vacuum. What cars run under boost on the hwy? I assume it is fairly flat road and speeds lets say up to 80mph

Same, both the Evo and the Focus sat in vacuum around -8 psi @ 85mph.

 

[wwillson]

Possible answer - machining debris

Toyota Finally Figured Out Why Its Twin-Turbo V6s Have Been Failing

The automaker has issued a recall for just over 100,000 of the V6s, which are found in the Tundra and Lexus LX.

jalopnik.com

 

[97prizm]

Wondering the same, because the Tundra is what I was considering.

Apparently Toyota has a release on why the Tundra engines are failing.
In a release from the automaker, it mentions that during production, machining debris may not have been removed from the engine. In affected vehicles, this can cause “potential engine knocking, engine rough running, engine no start and/or a loss of motive power.” Former Jalop José Rodriguez Jr. got Toyota to give more detail of how exactly this engine failure can happen:

The carmaker says the recall applies to models “with a specific V35A engine that contains crankshaft main bearings which allow the crankshaft to rotate within the engine assembly while running. During a specific production period, there is a possibility that engine machining debris of a particular size and amount may not have been cleared from the engine during manufacturing and subsequently contaminated the engine assembly during the production process.”

 

[edyvw]

Possible answer - machining debris

Toyota Finally Figured Out Why Its Twin-Turbo V6s Have Been Failing

The automaker has issued a recall for just over 100,000 of the V6s, which are found in the Tundra and Lexus LX.

jalopnik.com

I call gaslighting. In both plants? If that happened in the US and Japan, than they have other issues to resolve not just this problem.