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Discussion Starter · #1 ·
Hey guys, been around this forum for a while but first post. I have a 2008 LMM with about 200,000 miles. Everything is stock. Driving this morning and it started blowing whit/ grey smoke really bad. No performance problems seem to run the same. Pulled over and looked it over, looks like oil coming from exhaust flange between DPF and catalytic converter. Smoke does smell like oil to me, or coolant seems to smell like hot metal. Also no sign of coolant loss. Any ideas? Turbo?
Thanks
 

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2011 Crew Cab 4x4 dully LML
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Should be very little movement up and down and/or in and out. Not sure what the measurements should be but when I seen turbos go bad you could see it with no problem because it will leave scar marks on the hosing from the impeller. You can open up the charge pipe from turbo to inlet intercooler to check for oil. The down pipe you know has oil in it since you seen oil at the flanges.
 

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Discussion Starter · #7 ·
Should be very little movement up and down and/or in and out. Not sure what the measurements should be but when I seen turbos go bad you could see it with no problem because it will leave scar marks on the hosing from the impeller. You can open up the charge pipe from turbo to inlet intercooler to check for oil. The down pipe you know has oil in it since you seen oil at the flanges.
Not any oil in inlet pipe, I don’t feel any movement in the turbo, maybe a couple thousands, no scaring or marks on housing.
 

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2011 Crew Cab 4x4 dully LML
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That is somewhat good news. Well now if is was me I would pull the down pipe to have a visual on the hot side of turbo. If oily then maybe even start with pipe off so you can see the oil leaking. Just be careful if you go this route. I have never seen just the seal go bad by itself the bearing usually whips out the oil.
Something to look at
 

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If the boosted intake charge is leaking from a boot clamp or a hole in the intercooler, the result is over-fueling/smoke since the intake charge is less than the ECM thinks there is so it's overfueled...
 

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2010 crew cab dually
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1st thing let's get a scan tool amd read the codes
In my experience light colored smoke comes from a lean condition or coolant in chambers one sniff tells you dark smoke results from a rich condition or overfueling if you prefer that term.

A boost leak will lead to a rich condition white smoke generally rules that out

Read codes write down and report back
 

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Discussion Starter · #15 ·
1st thing let's get a scan tool amd read the codes
In my experience light colored smoke comes from a lean condition or coolant in chambers one sniff tells you dark smoke results from a rich condition or overfueling if you prefer that term.

A boost leak will lead to a rich condition white smoke generally rules that out

Read codes write down and report back
I have a scan tool, and there are no codes, the smoke doesn’t have any smell of coolant and I have no coolant loss.
 

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Test upper rad hose in morning should be squeezable not rock hard this will usually be a tell if youve got a bad head gasket if it were fuel starvation id expect some codes indicating low rail pressure etc
 

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I used a old school push button starter tool. One ends clamps to hot side of battery and the other end clamps on the starter solenoid. Not sure it that was the correct way, but that is my go to tool I use to verify compression, starter working, and/or to gain oil pressure after major work.
 
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