Does a turbo have to work harder when towing?

[y_p_w]

I was just thinking about years ago I was checking out some message board and some guy is asking if there's any way to disable the turbo in order to protect it from damage. His rationale was that he would be towing and that it would be stressing the turbo beyond what it would normally have to do. My contention was that even if one could be disabled, it would make it harder on the engine since the use of boost is designed into the engine (lower compression ratio) and it would probably need to be revved higher to make up for the lack of boost.

Now I started thinking about it, and turbos are really just regulated and hit the maximum designed pressure pretty easily. I don't think that it's necessarily stressing out one. If I'm cruising at 3500 RPM then it's going to be providing boost anyways. Is it really going to be doing anything it isn't already, even with a heavy load?

 

[RooflessVW]

The only thing to possibly worry about would be EGT, maybe oil temp.

If you're all stock, then there is nothing to be concerned with.

 

[The motor guy]

Spins faster, but it's designed for it.

 

[Rand]

the turbo doesnt "work harder"

The engine "works harder" when towing.

unless you have some kind of racing tune.. it will be fine..

of course thats assuming they "allow" you tow anything with your turbo car.

 

[E150GT]

I knew a guy who had a Ford 6.0 and he was towing and the turbo happened to die while doing so. It ended with him having no power to pull the load. Or so he says.

 

[Drew99GT]

If the boost is the same, it likely won't spin any faster, but with a higher load on the engine and running full boost for longer periods, it will get hotter than normal IMO. The new Fords though are so stress tested from the factory that you'd have to pull over max weight up something like I-17 north out of Phoenix in August to do damage.

 

[KrisZ]

Every single engine can provide different amounts of power at the same RPM, therefore work "harder". Cruising on a flat land at 3.5k RPM will require less throttle opening and less fuel, hence less work, than climbing a 10% hill at the same speed and RPM.

The same goes for turbocharging. The RPM may be the same, but the boost provided will be different, it all depends how much fuel is being burned at any given time and how much of the exhaust gasses are actually hitting the turbine vanes.

 

[Quattro Pete]

Originally Posted By: E150GT
I knew a guy who had a Ford 6.0 and he was towing and the turbo happened to die while doing so. It ended with him having no power to pull the load. Or so he says.

If your turbo fails, the car will likely go into a limp mode that will severely reduce power even beyond what turbo can provide.

 

[Chris142]

Originally Posted By: E150GT
I knew a guy who had a Ford 6.0 and he was towing and the turbo happened to die while doing so. It ended with him having no power to pull the load. Or so he says.
sorta like my na diesel lol

 

[DrRoughneck]

Originally Posted By: Rand
the turbo doesnt "work harder"

The engine "works harder" when towing.

unless you have some kind of racing tune.. it will be fine..

of course thats assuming they "allow" you tow anything with your turbo car.

This.

Since turbos are spun by exhaust gases coming from the engine, it's the engine's work that spins the turbo.
There is a point where the turbo can spin too fast and the EGR is there to vent some of the extra air pumped by the turbo into the atmosphere rather than into the intake port. Setting th EGR to open at a lower pressure would cause less air to be pumped into the engine and the engine would have to spin faster to generate the same amount of power (less efficient, the turbo's work is wasted). Faster engine RPM results in more exhaust gases and hotter turbo. As counter-intuitive as it sounds, limiting the turbo's performance causes more engine strain to generate matching power.

Nearly all semis - whose purpose is just that: towing - are turbocharged. RPMs are kept low, turbos are always spun to peak efficiency. They last for 20k hours between rebuild.

Hope this helps understand the cause/effect of turbos.

 

[y_p_w]

Originally Posted By: DrRoughneck
Nearly all semis - whose purpose is just that: towing - are turbocharged. RPMs are kept low, turbos are always spun to peak efficiency. They last for 20k hours between rebuild.

Hope this helps understand the cause/effect of turbos.

I get that most diesel locomotives are turbocharged. The big diesel engines from General Electric, Cummins, or Caterpillar/EMD are designed to operate at constant RPM, and I suppose the turbo is tuned for that kind of operation.

 

[Cujet]

Certainly, the higher the engine load, the faster the turbocharger shaft spins, and the more "work" it does. More engine output requires more air, that additional airflow is provided by the compressor, which is driven faster and is compressing much more air.

Here is a Ford Raptor's 3.5L Ecoboost under high load:

You had better believe the turbocharger is doing more work under high loads. MUCH MORE

And, this being an oil forum, the picture clearly illustrates why synthetic oils are a good idea with modern turbochargers. That level of heat can turn oil into "coke". BUT BUT BUT the turbo is water cooled.... Yes, it is, however, the turbine and shaft are not water cooled, they glow nearly white hot, and that heat rapidly transfers the quarter to half inch down the shaft and into the oil lubricated bearing.

Yes, modern turbos are designed to prevent coking. Or more accurately, to better tolerate modest coking. Use a quality synthetic and avoid problems.

 

[eljefino]

Disabling the turbo would be massively stupid.

He should just put in a boost gauge if he doesn't already have it, keep his foot out of it so as to mentally tell himself he "isn't using the turbo", wash the bugs off his radiator and

Not knowing his vehicle, he could get into thermal runaway where he runs hot, pulls timing, and runs hotter until he conks out. 18 wheelers are designed to go 100% for days but possibly not a sports car.

 

[Quattro Pete]

Originally Posted By: y_p_w
If I'm cruising at 3500 RPM then it's going to be providing boost anyways.

Not necessarily.

 

[Andrew1972]

Generally a vehicle towing tends to rev motor more due to downshifting for needed power which in turn calls for more boost. So a general statement is turbo works harder or really more often under boost while towing.

 

[Lenny5160]

Originally Posted By: E150GT
I knew a guy who had a Ford 6.0 and he was towing and the turbo happened to die while doing so. It ended with him having no power to pull the load. Or so he says.


Been there, done that with a brand new 2002 7.3L Ford. Limped it about 200 miles back home (while towing a ~18,000 lb trailer) with the exhaust glowing the whole way. Brought it back to the dealership Monday morning and never saw it again. Had to wait all summer for the 2003s to come out.

 

[bullwinkle]

Originally Posted By: E150GT
I knew a guy who had a Ford 6.0 and he was towing and the turbo happened to die while doing so. It ended with him having no power to pull the load. Or so he says.
Yes-after the dealer replaced the radiator on my 6.0 PSD work van they didn't tighten the intercooler hoses enough, one blew off-lots of smoke/noise, very little power.

 

[y_p_w]

Originally Posted By: madRiver
Generally a vehicle towing tends to rev motor more due to downshifting for needed power which in turn calls for more boost. So a general statement is turbo works harder or really more often under boost while towing.

But what I found rather odd was the notion that somehow stopping the turbo from doing its thing was going to be easier on vehicle when the idea was to tow with it.

Of course a turbo is pretty integral to an engine where its used.

 

[mjoekingz28]

What is the major threat to EGTs? Is it fuel burned, RPMs, ambient temp?


Does a turbocharger really ever work 'harder'? I don't think so since it is probably governed with a pop off valve when it reaches a certain level of boost or rpm. So, I would guess it can only 'work more often'.

 

[JHZR2]

Turbomachinery is life rated based upon time at temperature. Erosion occurs as well.

Higher/more boost equals higher temperature. Being at a higher boost level longer equals more time at temperature.

You should generally expect everything to be more stressed/ shorter longevity when towing. For the Turbo, you're essentially trading end of life performance, so if the machine is designed for some number of hours at some condition, you'll get some fewer hours at some other condition. It could be an exponential decrease in life,,,

But Id expect that modern torture testing on the components would ensure reasonable life under bad conditions. The wildcard is that accelerated age if tests don't account for natural age if of all sorts of bits and pieces in the vehicle.