Hi everyone,

I have an '03 Cummins HO in a 2500 and a buddy of mine has an '08 2500 6.7 Cummins in his...

He took his truck in for an oil change and the dealer told him that at his 30,000 mile service, he should have his valves adjusted.

This brought several questions to my mind. First of all, when I check the web I see statements about 12-valves vs. 24-valves and manual adjustments vs. automatic adjustments. Basically, I read that the 12v's need their valves adjusted and the 24v's have automatic valve adjustments. I'm not sure what it all means.

Now, I'm not a mechanic by any stretch. I use my truck to pull a 31' 10,000lbs speed boat and I'm just happy I can still pass people! :-)

I don't know if my truck has 12 or 24 valves, automatic adjustment or what. I don't know what my friends truck has either. My worry is that the dealership was trying to sell him service that he didn't need. I've read that with manual adjustments, you don't need to worry about it until 100-150K miles... certainly not 30K.

So, what do you guys think (or know) about this stuff? My truck is almost at 100K so I'd like to know whether or not I need to mess with the valves and I'd like to be able to help my friend call BS on the dealership if they are trying to sucker him.

Any help, clarification or advice would be appreciated.

Thanks to you all in advance,
Michael

 

you have a 24 valve. i have never heard of "automatic" adjusting. someone else needs to jump in here for more info. my truck has 114k on it and now i wander if i need to worry about checking the valves. it runs strong and no noises out of the norm.

 

i thought it was something like every 60,000miles you should or its recomended to get them adjusted. on that note i could be wrong, but if someone knows for sure, and what the adjustments are spec wise, it would be nice to see it listed here.

 

From wha I've read 24 valve trucks are recomended to have the valves checked at 125K miles. I think the 12 valves are similar to that too. I doubt the 6.7 need valves adjusted at 30k, sounds like a dealer scam.

I also have never heard of automatic adjusting valves on a cummins.

 

All Cummins motors are manual adjustment of the valves. The specs are .010 intake and .020 exhaust on the 5.9. Set the engine at TDC on #1 and adjust as follows 1I,1E,2I,3E,4I,5E. Rotate 360 deg so it is at #6 TDC. Adjust 2E,3I,4E,5I,6I,6E.
Re install the valve cover and your good.

 

06 up CTD is .026 exhaust if I'm not mistaken.

 

I set mine at .006" intake and .015" exhaust. Seems quieter and smoother. Been that way for 30k miles with no issues.

 

Adjust them between 100,000and 150,000 miles.

 

this is the info on my 06' valve cover. (not sure what earlier model settings are)

 

My Dodge service manual says valves at 100,000 and every 150,000 after that. Cummins just says every 150,000.

 

i have a 90 with 207,000 miles and the thing was a farm truck i adjusted the valves and they were barely out of adjustment.

 

I adjusted the valves on my old 06 after 60k. all i noticed was the noise. It made the engine quieter. Some where out farther than others. Man that #6 cylinder is a knuckle buster.

 

Tell your friend to read his owners manual. Mine says at 150K miles. I'm not bashing anyone but, if people would read the owners manual they would not be so open to being scammed by the dealer. It like the dealers that say "you need an injector cleaning service". My answer to them is, show me where that is in my owners manual........

 

Just because it isnt in the manual doesnt mean it isnt a good idea. There are no two trucks that will wear (or break) the exact same.

 

To obtain accurate readings, valve lash measurements AND adjustments should only be performed when the engine coolant temperature is less than 60° C (140° F).

VALVE LASH LIMIT CHART INTAKE EXHAUST
0.152 mm ( 0.006 in.) MIN. 0.381 mm (0.015 in.) MIN.
0.381 mm (0.015 in.) MAX. 0.762 mm (0.030 in.) MAX.
NOTE: If measured valve lash falls within these specifications, no adjustment/reset is necessary. Engine operation within these ranges has no adverse affect on performance, emissions, fuel economy or level of engine noise.