Been a diesel mechanic on industrial engines for 15 years but new to the whole pickup world. Purchased an '05 Dmax and it is straight piped. When I get on the throttle I get the loud turbo hiss. Looking for the deep throaty growl. Any help is greatly appreciated

Check that the intercooler couplings are tight, 05s leak there with a tune in it,

All pressure hoses are tight. Are there any mods to the turbo to loose this noise. Full throttle sounds like a fighter jet taking off?

All pressure hoses are tight. Are there any mods to the turbo to loose this noise. Full throttle sounds like a fighter jet taking off?
sorry to break it to you but exhaust noise and turbo whistle in a diesel go hand in hand. cant really have one without the other. most believe turbo whistle is desireable. i have a turbo back straight pipe on my lb7 and it is a deep throaty growl at idle and just cruising but will roar when you get on it and you can definately hear the turbo. if you just want a rumble and no turbo get a big block gasser but if you want a great running and sounding truck learn to love the turbo and keep it the way it is.

4 inch MBRP turbo(downpipe) back system.

The 05 engine has a VVT turbo,( varible vane turbo) controlled by the computer, not much you can do apart from changing to an aftermarket turbo, I had mine straight piped and had the same noise so I fitted a performance muffler pretty much straight thru but it added a howl to it.

All pressure hoses are tight. Are there any mods to the turbo to loose this noise. Full throttle sounds like a fighter jet taking off?
Your talking about the rush of air sound as you get closer to WOT? You have to get a programmer. I'm not sure of the particulars but I've got a straight piped LBZ and I'm thinking I'm going to program mine as well. I can't get used to the sound, like a jet liner spooling up for take-off. You'll have to go to the exhaust mod section and dig a little. http://www.dieselplace.com/forum/forumdisplay.php?f=84

when you say straight pipe, do you mean STRAIGHT as in no muffler and CAT, or do you have one or both?? If you have a true straight pipe without the CAT and muffler then you are going to have alot of whistle, that is the nature of these trucks.

Mine whistles a lot when I first start it up or sit still. You can also hear the vanes adjusting in the turbo from time to time. When I step on it the whistle kind of disappears but I'm not sure what it sounds like at the pipe. I think it's a deep tone cause I can hear it bouncing back off the concrete walls and bridges when I pass. Just FYI, mine is straight piped, no muffler no cat, just a 3.5 inch pipe with hardly any bends going to the back.

Mine has a muffler that resembles the looks of a cherry bomb, but I have no cat. It pretty much sounds like a fighter jet at all times. I personally think it sounds cool but I wouldn't mind getting that mean sound that a Cummins has. That is pretty much impossible though.

yeah its due to the VVT it the rush of axhaust backpressure past the hot side of the turbo/varible vanes in the exhaust side of the turbo doing their thing to get the turbo spooled up faster like a small turbo and when the boost comes up they back off or relax or OPEN up to make the sound of a big turbo or a regular styler turbo without the VVT. MIne does the same thing too. I kinda like it. But I still have the old school 12 valve cummins to get my fix of the old style turbo/diesel sound. :) hope this helps

Moved to Fuel System, Air, Exhaust, & Emissions Upgrades...

it is perfectly normal man, no worries. We get this call all the time. The variable vane turbo makes some funky noises at idle.

I think he is talking more about the ear piercing hiss/swirling sound at WOT. I had the same thing too on my LMM. I installed the DiamondEye Downpipe and it sounds MUCH better at WOT.

get efi live you can change the sound and the way the vane is in the turbo and really make it growl like a big block:cool:

yea i have thats done to mine and wow its sweet lopy idle