blue smoke

test drove a 08' 6.4 and i drove it town a few miles and it was great, I got on the on ramp for the highway and started to put my foot into it and for about 100 yards blue smoke was coming out the tail pipe, After that it was fine for the rest of the test drive... i really like the truck but that kinda scares me, any ideas? FYI its all stock with dpf and 86k miles

seems like that is what the 6.4's like to do, its weird. I have driven in back of alot of stock ones and they randomly release blue smoke for like 100 yards

Its probly due to a failing dpf or possibly cracked a one. The contaminents will hold in the exhaust after a drive and will start to burn out once it gets heated up. I see this in alot in trucks at dealers that do not get drove a whole lot and they dont get the chance to go into regen mode.

And like he said above that is due to a failing dpf. And they are more prone to do it when moisture is present or raining. There is a ford bulletin about this exact problem. Mine did this and was replaced under warranty. Then I sold the dpf and almost got back what I had in the whole delete

Not sure of the reason, but now that it is getting cold around here. (under 20) I have seen a lot of what I assume are stock 6.4 trailing quite a bit of blue smoke. My truck smokes a little blue (assuming unburnt fuel) When it is warming up with a race tune.

If your buying the truck to keep it stock, I would be concerned. But since your on this website, that probably won't happen so just buy it an mod it lol.

Big tunes I've noticed tend to smoke a little blue during warmup.

Stock trucks with DPF/Cat on them seem to smoke white when cold.