I have a 2002 LB7 with 166026 miles and stock from day one, it's smoking at idle. I have had the Balance rates and injectors check with two differant dealers. I have had an oil sample done at Ziegler and it's fine.
The last dealer told me it maybe the exhaust side seal on the turbo not sealing at lower oil pressure when idling and as the pressure increases it seals back up. Can this happen.

mjdmax

Nobody!!!!!!!!!!

Oil sample reading @ 5797 miles on it.

Soot 0
sulfation 19
oxidation 16
no fuel
no antifreeze
no water
potassium 1
copper 2
sodium 3
iron 4
chromium 0
aluminium 2
silicon 3
lead 2
tin 0
pq-ferrous dedris 4

I have never heard of it happening on a duramax but its not out of the question.

It is a big problem on Fords

the seal does not work that way, you would have a bad seal or oil drain blockage check your air filter. if you live/work near grain elevator, replace it. hows your fuel filter, did your fuel station get the biodiesel, and have any problems. when bio was mandatory, lot of stations got bad fuel, enough that minnesota stopped that policy. restricted filter will not allow enough fuel to get proper atomization, leading to smoke(blueish)

when bio was mandatory, lot of stations got bad fuel, enough that minnesota stopped that policy.

I don't think the fuel is whats bad, normally the stations don't drain their tanks of water like they should before they switched to bio. Happening in Cincy for bio and ethanol.