Have a F350 with 6.4 blowing blueish smoke from beneath cab during regen. Wondering if anyone else has experienced this? Bought it used a month ago, has 51,000 miles on the clock.

 

Well you might have an exhaust leak or something leaking onto the exhaust causing the smoke. Are the inside of your tailpipes really black? I would bet you may have a cracked DPF.

 

This may apply: Exhaust leak in engine compartment:
Some trucks may have an exhaust odor inside or exhaust smoke may be visible around the front. This could be caused by a leak at the turbo outlet from a misaligned downpipe. Verification requires disconnecting the turbo oil supply tubes (replace the banjo sealing washers, W302474) and removing the turbo heat shield to inspect. If the leak is at the turbo outlet, the downpipe will need to be repositioned to seal correctly, with a new downpipe to turbo gasket (7C3Z-6L612-B) and v-band clamp (7C3Z-5A231-AC), and new nuts for the downpipe to catalytic converter flange (W711407-S900). If properly installed, the downpipe will be 11/16" +/- 1/8" from the frame rail. TSB 07-7-7

 

inside of tail pipes clean as a whistle; smoke only happens for a minute or so during regen, not for the entire regen.

 

thanks senix, sounds like you hit the nail. exhaust order inside the cab and smoke from underneath; only happens for a minute or two during regen usually.

 

provide that tsb to your service dept and get it looked into...

 

Exactly what I had in mind; thanks again, senix!