Turbo Whistle

Shawn T · July 10, 2005

I have the LB7. I have ridden in a few others and there is a noticable "turbo whistle" at low speeds and upon acceleration. The same goes for the LLY. I can never hear mine. Only when I am in an alley or along side of any object that can reflect the sound, barely. I can feel it spool up on take-offs, because I get that "lunar" take-off at about 2000 RPM's. Should I be able to hear the turbine over the motor? Should it be relatively quite? Would a code pop up if there was a problem with the turbo system, or is it all mechanical? I don't care for the extra noise, but I want the turbo at it's full capabilities. Is this "quiteness" normal, or am I just overreacting? I posted this topic once before and never really got a definate answer. How do I check the boost pressure?

Shaners · July 11, 2005

I can hear mine in my '05.

WileE1 · July 11, 2005

I can rarely hear mine. Only time I do is on the highway when it's in 5th and I step on it to pass someone. I used too and kinda miss it

The motor is noticably louder even after the injector and FPR change? Hmmmmm

dewfpo · July 11, 2005

It's possible it just your driving style. Perhaps your not a leadfoot. The whine you hear is the turbo/bearing spinning at 10's of thousands of RPM. This is normal. When road or wind noise are present you won't hear the turbo whine, unless you punch it. Could even be the type of oil you use or how often you change it. All in all it sounds normal to me and I wouldn't worry about it.

DEWFPO

Shawn T · July 11, 2005

DEWFPO,

Thanks, I actually sent an email to Jim at thedieselpage.com. He pretty-much said the same thing. An aftermarket intake or free flowing exhaust could make it louder, or just vary from truck to truck. The "whine", or the "zing" you hear is actually the bearings, as you mentioned. He also said a low boost pressure would most likely throw a code, such as, low MAF. It is just wierd, when I jump in my buddy's truck (same truck, totally stock) you can hear the turbine making that zing every time he even feathers the throttle, muck less hammers on it. I heard a guy hammer on his 05 DMax the other day while I was filling up. When he went by, all I could hear was the turbocharger. Maybe I just got lucky with a very, very quite diesel and a well insulated cab.

BlackSilver · July 11, 2005

I have an 03 LB7, and can only hear a whisper of turbo noise, and you have to listen very carefully.

KyleBst264 · July 13, 2005

I can only hear mine when I'm towing my trailer down the highway, with the cruise set, windows up and radio off. And then, I have to be coming onto a grade, I will hear it very faintly. If the radio is on, I won't hear it at all.