Auto (Diesel) Mechanics Enter Here For Turbo Question

[olds]

I know turbos generally seem to last 60,000 - 80,000 miles in cars. How about trucks? The specific vehicle is a Ford Super Duty, 7.3 Turbo.

 

[Cyberian]

Originally posted by: oldsmoboat
I know turbos generally seem to last 60,000 - 80,000 miles in cars. How about trucks? The specific vehicle is a Ford Super Duty, 7.3 Turbo.

You talking about the turbo itself, or the engine that's turbocharged?

 

[olds]

Turbo. I hear that heat is the issue.

 

[NutBucket]

Originally posted by: oldsmoboat
Turbo. I hear that heat is the issue.

Yep. Heat is the enemy w/ turbos. It hurts performance and kills the bearings.

 

[Bignate603]

I was under the impression that turbos lasted longer then that if well maintained. I thought the biggest issue was the constant supply of lubricant.

 

[Eli]

Originally posted by: Bignate603
I was under the impression that turbos lasted longer then that if well maintained. I thought the biggest issue was the constant supply of lubricant.

Yes.. Well, more like the constant supply of lubricant thats actually lubricating. The high heat experienced tends to break the oil down fast, so you have to watch it.

Fully synthetic oil is very highly recommended for turbos.

 

[olds]

From what I can tell, they seem to last longer in diesels (trucks) than gas (car) motors. It would be easy to surmise that since diesel is not as flammable as gasoline, less heat results from the combustion process increasing the turbos life. Is this true/correct? Or is there another reason?
I am looking at getting a truck with a diesel motor. It has a turbo and that got me to thinking.

 

[Iron Woode]

Originally posted by: oldsmoboat
From what I can tell, they seem to last longer in diesels (trucks) than gas (car) motors. It would be easy to surmise that since diesel is not as flammable as gasoline, less heat results from the combustion process increasing the turbos life. Is this true/correct? Or is there another reason?
I am looking at getting a truck with a diesel motor. It has a turbo and that got me to thinking.

Diesels generate a lot of heat due to the compression of fuel which is what makes power. Ever examine a diesel truck's radiator? Its huge.

Diesels in most trucks don't rev very high either. Therefore the turbines don't spin as fast (rpm) as a normal gasoline Turbo car's would.

Why not ask a diesel mechanic about the life span of the turbo itself? Or about the whole drivetrain for that matter?

 

[Marshallj]

Originally posted by: oldsmoboat
I know turbos generally seem to last 60,000 - 80,000 miles in cars. How about trucks? The specific vehicle is a Ford Super Duty, 7.3 Turbo.

They last longer than that. In my old 1986 300ZX turbo, I replaced the turbo at 160,000 miles. And in my current Z, I'm at 110,000 miles and I still have the original turbos.

 

[Marshallj]

Originally posted by: oldsmoboat
From what I can tell, they seem to last longer in diesels (trucks) than gas (car) motors. It would be easy to surmise that since diesel is not as flammable as gasoline, less heat results from the combustion process increasing the turbos life. Is this true/correct? Or is there another reason?
I am looking at getting a truck with a diesel motor. It has a turbo and that got me to thinking.

The exhaust gas temperatures (EGT's) are much lower in diesel engines. The turbos therefore do not run as hot.

 

[KokomoGST]

To another degree it really depends on the design & manufacture of the turbo itself... some turbos will be more solid than others and some more fragile. But for a well-maintained turbo that's not being over-worked (constantly demanding more pressure than it can provide efficently) they can last a LONG time.

 

[Marshallj]

Originally posted by: Iron Woode

Diesels in most trucks don't rev very high either. Therefore the turbines don't spin as fast (rpm) as a normal gasoline Turbo car's would.

Why not ask a diesel mechanic about the life span of the turbo itself? Or about the whole drivetrain for that matter?

The speed the engine revs is unrelated to the speed the turbo revs. The how much exhaust is moving through the turbo and how large the turbo is determines how fast the turbo spins. If you upgrade the turbo on a car with a larger turbo, it will spin at a lower RPM. The 2 small turbos in my Z rev to about 150,000 rpm, while a large single turbo upgrade may only spin at 60,000 rpm.

 

[Iron Woode]

Originally posted by: Marshallj

Originally posted by: Iron Woode

Diesels in most trucks don't rev very high either. Therefore the turbines don't spin as fast (rpm) as a normal gasoline Turbo car's would.

Why not ask a diesel mechanic about the life span of the turbo itself? Or about the whole drivetrain for that matter?

The speed the engine revs is unrelated to the speed the turbo revs. The how much exhaust is moving through the turbo and how large the turbo is determines how fast the turbo spins. If you upgrade the turbo on a car with a larger turbo, it will spin at a lower RPM. The 2 small turbos in my Z rev to about 150,000 rpm, while a large single turbo upgrade may only spin at 60,000 rpm.

What I meant was it probably isn't making a tremendous amount of boost. Turbos still spin faster when the engine revs higher and until the waste gate kicks in to release some of the excess pressure that is built up.
The benefit of twin (small) turbos is the reduction of lag. Less mass to spool up means quicker reaction time for the car. It is probably easier to tune a car's turbos when you have 2 smaller ones.