I have a 2003 CTD with the California SO. My truck is making some pretty evil noises right at about 55, or just when it shifts into OD. It happens everytime the truck shifts into OD unless it's a situation where I've really got my foot in it.

I live in an area where there are lots of city streets that have 55 mph zones so it's unfair to compare this to something like a freeway on-ramp. It always happens when you take off from a light at a normal "in-traffic" pace and as I slowly climb up to the OD shift point....BBBUUURRRPPP as it shifts into OD.

What is happening when I hear this noise. I've asked this question before and was told to just shut-off the OD and the problem would be solved. That does work, but then you spend all day spinning at super high RPM's.

I don't know if this noise hurts anything but I would really like to understand what the truck is doing when I hear this. Is anyone else having this problem???

Thanks,

Chad

 

Sounds like the turbo is "barking". Try to vary your shift to OD at a little lower speed, by a lighter foot on the go peddle, to see if that helps.

 

I've heard that definition before but, what is actually going on? What makes the bark? Is it hurting anything?

Thanks,

Chad

 

It is the rapid change of drive pressure when the tranny shifts. The engine was pushing air at 2500 rpms...then 1900 rpms...the air stacks up on the compressor side of the turbo and makes that "chuffing" sound for a second. It sort of stalls the turbo for a second. I don't think in your case that is is harmfull. You can learn to drive the truck around it so that it does not happen.

 

Here is a couple of things that will help get of some the Turbo Bark also:
Go thru the turbo exhaust clamps and tighten them down, some have come loose:
Go thru the exhaust and make sure that it has atleast .5 to 1" clearance all the way around:
These may sound like stupid things to check but they will help with the bark, and heop spool up the turbo better.
As far as the bark is concerned you will get some as the turbo reaches max boost and then the exhaust is opend to allow it to bleed off without disentagrating.