An RV dealer that services Dodge/Cummins indicated that for long service life, not only should the valves be adjusted at 50K, but also a decarbonization should be done as well.
Is there any validity to this? (Another up sell?)
He did indicate that a Cummins Service center may give better/more consistent service than Dodge. Any coments?
Also, there seems to be mixed reviews on Valve adjustment, between 50 to 100k. Again is Cummins preferred, if you can't do it yourself?

 

I wouldn't run DeCarb through your truck , with a VP-44, fuel lubricated and cooled pump. We use that mainly in the old 855's, and when you do that stuff gets Hot . just try holding on to the fuel lines, and watch the blisters come up. As far as valve adjustments (first one) 125,000 then ,check them around 50,000 there after. It's easy to do yourself, and the instructions have been posted on here before , use the (search) feature.
JBHale

 

1st off diesels do not carbon up
2 the valve adj. should be done off the show room floor.....I guarntee thet are loose as a goose..

 

It is not the engine that Decarb was designed for , it was for the injectors. For STC, Top Stop, and Celect injectors. Carbon from the combustion of the fuel can collect and seal off the holes , blocking the injector from spraying correctly , decreasing fuel ecconomy and creating other problems. Decarb cleans this carcon without having to remove the injectors , and Engine brakes which is costly. It basically is one of them (nice and fuzzy) things.

 

Really I work at a deisel shop and today spent 1 1/2 hours beating carbon out of a detrot 6 71 head even after it had been in the caustic vat for the weekend. They will carbon up*

 

Sorry, but in this case I do not agree with you. Diesels do carbon up, specially after extended periods at idle speed.
Many years ago we had a Cat D4 that was gutless and would not rev properly. I pulled the head and found that all the intake valves were carboned so bad around the valve stems that the carbon almost filled the space around them. Had a hard time removing all the carbon so the we could remove the valves. All I did to that engine was remove the carbon from all the valves and passages, gave the valves a quick grind and slapped it all back together. It ran like new with full power after that.

Off topic, but I remember that same D4 loosing a track in a field that we had flooded to plant rice. Now that was fun, trying to jack it up in that deep mud. Not! Even a 2 foot square plate sank under the jack. Then try manhandling that very muddy and slippery track back in position. Talk about taking a mud bath!

 

On the CTD it would have to be from idling. I never idle mine and at 241,000 when tearing it down, the head was great, no carbon under the valves.