Hello all here is my deal, I bought or stole an 04 Columbia in march form the local used freightliner dealer, it was an ex penske truck, I have a friend at penske and he dug up all the info in the truck, it was in an accident and everything external on the engine was replaced, so lets put it this way, everything that is bolted to the block or in the compartment was replaced at 379500 miles, I bought the truck with 388000, i know what you are thinking what are you nuts buying a truck that you know was wrecked, but if I throw out what I paid it will make sense, anyway I am at 419k now I am a maintence person so oil is changed every 10k air fuel etc all done when its time, the truck runs great and has really good power and I am getting 7 mpg almost all the time, there is one thing though and it has me a bit concerned, shifting from 9th to 10th every so often like once a week it will cough, it is brief maybe 1.5 to 2 seconds almost like it sucked air, blow a puff of pretty black smoke then all is fine, it really wont happen for another week give or take, so am I screwed, I do have a warranty from frgtlnr and it is extensive, so hopefully if it is a major deal it will be covered just want some input here b4 I go there. Honestly it is so infrequent and brief it really dosent bother me that much, also at this point should I be thinking of having the shop go round the rack and do a check up even though all is well besides the cough.
Thanks in advance
Dave

Can you tell if the cough is air or fuel? Does the engine act like's it gonna die or just cough and then off it goes? If you are pulling really hard in 9th and shift you might get some air rushing back toward the air cleaner because the turbo is spooled up hard but the engine RPM is too low to use the air (aka stall). This is somewhat common on trucks with a large spread between 9th and 10th.

Does it happen during any other time? Is it a standard waste gated turbo or an early VGT truck?

its an early VGT and You hit it on the head I didnt mention because it would have been too long, but if I let it rev to 1800ish in 9th which brings me to 65 MPH and then make the shift it never happens, I am a gentle driver so this is un natural to me shifting easy around 1550 16 is more my style, (no I am not a lugger LOL) but that is what is happenning so this is common, or does it happen only on wasted turbos or is it because it is a vari geo, and yes I am not sure of the numbers but 10th is very far from 9th, it has taken me quite some time to learn how to drive the truck right, as for the past 17 years I have been in Macks and only Macks which are quite different from this truck, But I will say this I expected this to perform like a line truck, and I have been pleasantly surprised, I have it set to 76 mph, and am impressed with the power I am a flat bed o/o and am heavy most of the time, I live in Mass and am runnng the N.E. always so hills are part of the deal, tell you what this truck with 47k on the deck would out pull my 02 ch613 with the e7-460 all day long, and as far as the ride goes well so far it has been good not as good as the ch but much better than everyone said it would be, all in all I do about 3000 a week here in Newengland Ny and NJ so he running is hard and the roads are worse, and this thing hasn't griped a bit, they tell me it is 515 hp but there are 2 stickers on the cover one says 475? @1800 then the other one says 515 so i really dont know someone said if the crusie is on it's 515 but 475 on the pedal, this makes no sence to me, and i feel no difference between the 2 but either way it pulls good and is doing very good milage wise,, I never thought I would say it and not be lying but I am really happy with My 04 columbia, Hey thanks so much for the response.

oh yeah on more thing that has really amazed me. this truck leaks nothing, I can idle for 4 hours and the spot where i was parked is dry, my macks leaked oil wth 10 miles on them, yeah there is some oil on the pan bolts but never enough to drop, it amazes me. Park it over the weekend in the driveway and no cardboard needed honest 419k on the motor and it is dry, weird, and i should probably find some wood to knock on b4 i screw my self.

i think detroit has got away from the oil leaks they had in the past.

It's possble the that vanes in the turbo are a bit sticky so it doesn't spool down as fast as it should. I'm not sure, but I seem to recall that there was some software updates for the early VGTs to help the vane sticking issue. I wouldn't worry to much, but would think about hooking DDEC up and runing the VGT cycle. Also don't forget to inspect the turbo itself, pull the boos and check the shaft/wheels.

It may have been a factory 475 that was uprated. Or you may be looking at the engine family and what you engine is rated for. You can give DD your engine number and they will tell you what it was shipped as and if it has been uprated.

I drive a 07 freightliner and under a hard pull it would cough, has done it a couple times. Maint says its egr valve and to let them know if it does this on a more consistint basis hasnt happened since then.

In my expereince. It is the EGR valve. As time goes on the "cough" will worsen expecially under load. I have had a truck that coughed every once in a while that had the egr fail open. I have also expereinced a truck that coughed all the time, and the egr was finally replaced after a few months not because of my nagging, but due to increasingly poor fuel milage.

can this also be the egr on a 09 isx cummings motor? mine starting doing it at 1400 rpm's and worked its way up to 1700 over a few months. im taking 3 day off in 2 weeks to go racing, and it will go to the dealer then. its getting really old tho.

Yes, it is possible for the EGR to cause that problem on an ISX as well.

Doma, has the truck had the updates done to the EGR? I don't remember the specific production dates, but that truck may have been shipped with the orginal style EGR and if it still has it I'd get it updated since you say it's still under warranty.

No matter what brand engine it is, if you do have an EGR valve problem it can get bad. If the valve sticks closed no worries. If the valve sticks open it'll beat up on the cooler and that can cause some issues, plus it loading the engine full of even more soot than it normally does.