High turbo noise

[Lar_s]

Just pulled a tough hill, towing my about 17k 5ver, pushing it hard to get past a wide load truck and the turbo went to about 20,000 or so... pretty loud wind up noise that is new to me. Wondered if it was normal.

The turbo normally runs up to about 15k on hills that aren't as tough.



Truck is a 2015, Ram, 6.7, 4500 miles.

Thx

[DavinD]

Fan clutch on my 6.0 Ford was super loud. Thought I was taxing for take-off. Haven't heard it on my 6.7 (hope I don't have to).

[marcsbigfoot20b]

You see the fan come on a lot on turbo diesels because of the extra 300+ degrees of the intercooler under full boost cranking up a large hill. The fan locks on when the air temp of about 205F (on my 7.3 Ford) hits the bimetal curled sensing clock spring which turns and allows the fluid to lock the fan.

What is annoying is when you are cranking up a hill at 70 mph or more (plenty of airflow) and the stupid fan comes on anyway dragging 25-30 hp, even though it shuts right off after 20 seconds of cresting the hill.

Im actually thinking of adding a windshield wiper squirter that is aimed right at the center of the fan clutch. When it locks on a hill, I can just push the button for 5 seconds of water and the fan should instantly unlock for a bit.

[GoPackGo]

Thank you. I learned something today.

[jus2shy]

GoPackGo wrote:
Agree. The last time that happened to me I glanced down at the temp gage and I could actually see it start to decrease after a very few seconds. It happens
fast.

Long ago I read that at normal NON-TOWING highway speeds, the fan isn't even needed in most vehicles because the 60 mph wind blowing thru the radiator is entirely sufficient to cool it.

What I don't understand at all is why GM/FORD/RAM don't use electric fans on their trucks instead of engine driven. It's wasted horsepower when you need it most. And I know all these trucks have HP to burn, but when going up a hill I want every one of them pulling instead of spinning the fan.

Tim

Simple, there is no electric fan system that's cheap and robust enough to actually move as much air as the engine mounted fans in use today to keep up with the number of BTU's modern HD diesels need to disperse. Our transit agency helped pioneer an electric cooling package for our buses, That cooling package which only deals with a radiator and intercooler consists of 8 or 9 fans to provide enough air flow through the radiator and intercooler. Both units are about 4 or 5 inches thick. A transit bus only has about 300 HP and 1,000 lb-ft of torque (Typically a Cummins ISL). And the system at full-bore draws over 100 amps. The alternators we use pump out 400 to 500 amps. At partial load it will intelligently throttle each fan individually depending on which unit needs cooling. Intercooler fans are ran almost constantly depending on ambient temps. Every diesel in a pickup would have to have twin alternators to power a cooling system of similar size. Granted, the transit industry doesn't have the economies of scale as the light duty truck industry, but the cooling system alone costs roughly half the price of a typical compact car. But over the lifespan of a bus and all the fuel it saves, it actually pays for itself and then some.

[GoPackGo]

Agree. The last time that happened to me I glanced down at the temp gage and I could actually see it start to decrease after a very few seconds. It happens
fast.

Long ago I read that at normal NON-TOWING highway speeds, the fan isn't even needed in most vehicles because the 60 mph wind blowing thru the radiator is entirely sufficient to cool it.

What I don't understand at all is why GM/FORD/RAM don't use electric fans on their trucks instead of engine driven. It's wasted horsepower when you need it most. And I know all these trucks have HP to burn, but when going up a hill I want every one of them pulling instead of spinning the fan.

Tim

[blofgren]

It is the fan; they ramp up quite quickly and run for a bit even after cresting a hill. It brings the temperature down very quickly, though! Enjoy your new truck; we love ours!

[Lar_s]

Agree, think it was the fan. I'm sure the heat went up cuz it was working hard. Was paying more attention to the hill and traffic. I was more used to my ISL 370 running behind me in the motor home so a bit new. The last diesel I had wasn't turbo equiped, nor is my farm tractor...

Thx for all the replies.

[ACZL]

I agree w/ what's been said so far. Either engine fan or possible boost/intercooler leak. If the intercooler it sounds like a "wooshing" or sucking and only happens when under acceleration/load. If the eng fan, the water temp should have come up to a "X" point on gauge, fan kicks on and temp should've come down. Sometimes the fan will stay on till you crest the hill, others it will cycle depending on length of hill. Like what others have said too, the eng fan sounds like a jet under the hood.

For farts and giggles, next time your in city traffic and at red light w/ semis around, listen to hear if you hear sounds similar to your when they take off from a dead stop on warm/hot days. Chances are their eng fans will kick in briefly as the sound will be greatly louder than normal diesel sound.

[N-Trouble]

Could be a boost leak if its not the fan clutch.

[Lar_s]

Thx .... I guess I have read most of the manual, even the 900 page one RAM sent when I kept calling with questions.... must have had a brain #$%^ on boost pressure. Fan kicking in could have been it... tough hill and topped it at 61 mph... way too macho but ... well, you know.

Temp didn't show a climb, but had to be up there.

Thx again

Lar

[hone_eagle]

Turtle n Peeps wrote:
If it's boost, Ram really stepped it up! :E

20 thousand lbs of boost. That's a bunch! No wonder that "Cummings" pulls so well. :W

OP it might be a good idea to read you owners manual cover to cover. A lot of good info in there.

Toyoda pulls the space shuttle Cummins powers the space shuttle.

[Grit_dog]

Possible combo of boost pressure getting the turbo to sing, cooling fan kicking in (roar) and active intake management switching to fresh air intake to lower intake temps.
Nothing wrong, you got a bad @ss truck!

[NinerBikes]

15 or 20 is probably manifold pressure in psi boost. Turbo's don't usually start making boost until 80 or 90,000 rpm and that's just barely anything, and 110 to 135,000 is where they really start flowing a lot of psi boost.

Another vote for RTFM.

[Turtle_n_Peeps]

If it's boost, Ram really stepped it up! :E

20 thousand lbs of boost. That's a bunch! No wonder that "Cummings" pulls so well. :W

OP it might be a good idea to read you owners manual cover to cover. A lot of good info in there.