Turbo or Trans Problem ?

[RDThompson]

I have an 2008 2500 Q/C 68RFe 4WD . I thought I had a trans problem but on reflection it may be a turbo problem.

I run my Engine brake most of the time and I'm usually a gear or two down to keep the revs up in traffic. I also lockout the O/D most times. My truck has been exhibiting a strange characteristic. It slows quite well with the E/B but sometimes will not accelerate after a decel unless I release the pedal completely and reapply the throttle. It usually occurs on long duration decel but it can occur at anytime I slow down with the E/B.

I initially thought it might be the transmission not shifting properly but when I was reminded that the E/B is built into the turbo I rethought the whole thing.

Does anyone else have the same problem with their truck?

I'm not getting any CEL alerts during these events. Any information would be greatly appreciated.

 

[jelag]

One of the big issues with the 6. 7 is soot build up... the tech's say by using the e-brake all the time your forcing full movement of the ring that controls the variable vanes in the turbo...

I'm wanting to believe that you've got full movement and nothing is sticking, but you describe a ring that moves to e-brake mode and than sticks sometimes as it tries to go back to turbo mode... or its not seeing the signal to go brake off/turbo on when you press the throttle... .

We've got an 08 5500 with the Aisan transmission an this truck now has 110K miles and has ran great the whole time...

If you know someone with a scanner which can read live time, I'd hook it up and monitor the throttle position switch to see that it's moving when you apply the throttle... or you might turn off the e-brake and see if the symptom goes away. . which would tell me that its the ring in the turbo sticking... .

Have you had the TSB that installs a cleaning port and had this cleaned... since our truck has never thrown a code, our dealer wouldn't do the mod until there was a problem... I've since got the TSB and will sometime when I get a minute pull the Turbo off and install the cleaning port...

Just my thoughts. .

 

[RDThompson]

Thanks, I was beginning to think in that direction. I will check into getting it cleaned.