We have the 2005 5.9 and today when we entered the interstate, punched it to get in front of an 18 wheeler, we lost low end torque but was already at 65mph. We heard a turbine sound and pulled into a rest stop, about a mile ahead. Cut the engine and the sounded like a turbine slowing down, like tire balancer after the balance run. Transmission still shifts ok but there is no low end power. Torque converter? Transfer case? High Presure fuel pump? or could a band have broken in the trans?

 

possibly a blown intercooler boot?

 

Check the ends on your intercooler. On some of the 05's they had plastic ends on it instead of metal. The end caps on my truck are plastic, and i'm currently trying to find an all metal one.

 

Thanks Highmileage and Big 3500. We will check the intercooler. Did not think of this option.

 

Might check the gasket between the exhaust manifold and your turbo as well. Just blew that gasket on my truck the other day cruising home.

 

Thanks, this might be the problem. Just replaced the turbo about a month ago. We had a higher pitched whine than normal so we took the air intake off and tried to turn the blades. Had some resistance but turned. Started the truck and the blades were not turning at first then started slowly. Replaced the turbo and solved the problem. The Turbo Exchange in Concord N.C. said nothing was wrong with mine..? $295.00 exchanged, so we swaped. The gasket just might have failed.

 

Well, no gasket problem, no inter cooler issues, no loose clamps etc. Think it may be the catalytic convertor is stopping up. Will loosen the exhaust and see if that helps. If it does, good buy convertor.

 

you might look at the exhaust manifold gskt where they meet the head.They are multi layer stee land can make a strange whistle when boosting(mine did) I looked closely and saw soot on the manifold and head. #5 was slight leak, 6 was pouring.

 

Well, Our computer has been out for a few days. The lost of power problem was a bad turbo. Removed the air intake and the nut was gone, the tip of the shaft just before the fins was missing, fins were chipped on the end. Fins were rubbing the housing as well. Removed the charge air cooler and found a few pieces of shaving but no nut. Searched in and out and found no other signs of damage or metal. Turbo exchange swapped the turbo, paid half the repair bill as well. Good guys to deal with . Running just fine now.