Help Needed knocking and smoking

[jocephus]

hey guys and gals ive got a buddy with a problem he has a 05 sd with 115k on clock all stock it has just started knocking in the top of engine on the pass side and white smoking bad. i can say he more than likely has egr problems but what would cause the knock it only does it when up to opperating temps. would a cracked head cause this? im going out to do some diagnostics on it tonight any help would be appreciated, like where to start.

 

[DaveBen]

jocephus. Have your buddy get the truck scanned by a good shop. The codes will tell the story better than spending all day guessing and throwing parts at it.

Dave

 

[jocephus]

codes

thats the funny thing the truck has no lights comming on and it runs great it justs knocks and smokes alot, no missing, power loss, or anything not even loosing coolant took cap off tank and no bubbles or anything. would it throw codes even if no ses light?

 

[Tman123]

My 7.3 Does. I get the two same codes almost all the time.

 

[mastrkee]

blown head gasket maybe