# turbo on 2008 f350 and 2007 f250



## DJMAUCTION (Oct 10, 2007)

Hi all.

heres the story, have a 07 6.0 turbo rarely gets over 25, its low when on the highway and slightly accelerating, seems ok to me, no issues

my 08 6.4 350...the turbo is always registering someting. it seems to be at 10 when slightly accelerating and if i go to pass or hit the cruise it jumps to 20-25

on the 07 6.0 I have to floor it to get it that high, is this all normal???


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## MickiRig1 (Dec 5, 2003)

I don't understand the question? I drive ambulances with all the PSD's.


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## DJMAUCTION (Oct 10, 2007)

the boost on the 08 is always around 8-12 psi. on low acceleration, its nothing on the 07 6.0 until i really press the petal down.... wondering if the boost/gauge is more active because its a small and big one ( turbo vanes?) and its the small one working on low rpms?????


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## ColliganLands (Sep 4, 2008)

the only thing i can think of is that it might have something to do with the 08(6.4l) having 2 turbos and the 07(6.0L) having only 1 turbo
Kyle


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## LawnProLandscapes (Nov 15, 2007)

DJMAUCTION;593007 said:


> Hi all.
> 
> heres the story, have a 07 6.0 turbo rarely gets over 25, its low when on the highway and slightly accelerating, seems ok to me, no issues
> 
> ...


the 6.0 only has a single stage turbo which isnt going to produce much boost when cruising at low r's until you get on it and need it... with the 6.4 they have a two stage turbo setup so the smaller turbo starts turning at lower r's and creates boost so when the big turbo kicks in there isnt any "turbo lag" and the larger turbo takes over. thats what i think your noticing in difference.


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## PRAM (Sep 30, 2008)

The 08 twin turbo has 2 stages.....if you hammer it then the 2nd stage kicks in...shouldn't kill mileage as long as you don't stay on it.


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## stroker79 (Dec 2, 2006)

Which stage is "Ludicrous Speed"???


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## PRAM (Sep 30, 2008)

My cc goes pretty darn quick !!!!!!!!


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## ColliganLands (Sep 4, 2008)

my 6.0 moves along really good, no lag at all. they did just have to replace almost 10k in parts including the turbo so that might also help it


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## Chaos (Jan 27, 2005)

Both engines use the same principle. The 6.0 liter uses a variable vane turbo which adjusts the boost based on RPM electronically (unlike normal turbos which use exhaust gas speed to directly determine the boost pressure). Obviously, the turbo cannot make 20 psi at 1 000 RPM, but you get the idea on how they tried to reduce the lag.

6.4's as everyone mentioned uses a "serial" or dual sequential turbo system with vixed vanes (thus much higher reliability than initial '03 6.0 models). Both turbos spin depending on exhaust pressure, but the smaller turbo gives early RPM boost and the rest is taken over by the larger vaned turbo, thus almost eliminating turbo lag.

We have an '06 Powerstroke and have the same problem. There seems to be a delay (controlled by the computer) before it decides to start up. Normal of course, but annoying as hell. I don't think we can blame it on the turbo lag, but there definately is a lag from the turbo. However, when that sucker kicks in, hold on to your nuts.

My friend slapped a chip in his '05 PSD and it reduced the lag alot, but 6.0 liters are known not to like just plopping in a chip. You should upgrade the other components as well (same goes for any vehicle for that matter.

*edit* Sorry, the 6.4 has a variable vane turbo on the second stage turbo


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## MickiRig1 (Dec 5, 2003)

I think without a doubt the 6.4 is the best Power Stroke yet. The computer controls the transmission to use the engine to it's best. There is very little lag in boast, I think it's designed to keep the boast low, at lower speeds.It improves driveabilty at so your not on the brakes all the time. The 6.0 and the 7.3 were like a Turbo or 4 barrel carbed gas vehicles. Once your in wide open throttle they just charge ahead to their red line.


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## Chaos (Jan 27, 2005)

If anyone is interested on more turbo information here's some links

http://www.holset.co.uk/mainsite/files/

http://en.wikipedia.org/wiki/Variable_geometry_turbocharger

As far as the 6.4 being the best engine, I would have to disagree until it's been around for over 10 years like the 7.3L. Which will never be the case since the Scorpion is on it's way into the trucks. For most years the 7.3 didn't suffer from emissions control like the newer engines, so electronics weren't necessary.

Today, with the number of sensors, amount of turbo pressure, moving parts JUST to control emissions......1 little sensor reads a fault and the whole engine stops working.


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## MickiRig1 (Dec 5, 2003)

A lot of people said the same thing about fuel injection and no distributer ignition. I am talking about the drivabilty of the 6.4 . Talk to me when my Ambulance reaches 100K on it.
It has 54K on it now and has not had an engine or proformance problem yet. I have drove the Power Stroke's and non-Turbo's since Ford put them in E-350's in the late 80's. I love the 7.3 but the 6.4 is no doubt a decent replacement.


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## Chaos (Jan 27, 2005)

ok Mick, you win, lol

I agree the driveability of the 6.4 is amazing, quiet, little to no lag and a heck of alot of power. I think the braking you experience is actually the torque converter locking up at low RPM. Kind of like an engine brake, it's pretty handy. And if you hit that tow/haul button, it gets even more extreme.


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## DJMAUCTION (Oct 10, 2007)

*fun fun fun*

so lately, my 6.4 sounds like a gasser not in Time, I mean when I give it fuel, you hear the injectors pissing, then when you let go the sound disappears and you hear a thud thud thud sound get lower and lower, gass it up again and the sound is just loud and stupid.

the truck has 2800 miles and I do not have time to [email protected]@#$ around at the dealers, I [email protected]#$ hate them all.

help me obi one micki your my only hope 

seriously I dont know why the engine is so dam loud on acceleration, and im not flooring it, just going normal speeds, no load on....rrrrggghhhhh I hate new trucks that sound like old ones...


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## matzke3 (Oct 15, 2008)

Sounds like possibly a boost issue. Are your boost numbers low? If you dont want to vist the dealer just yet Checked your intake boots and clamps.


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