6.7L Gear case oil leak

[jmorse]

Have a 2016 3500 C&C with 125000 + miles on it. Oil is leaking from the RF lower corner of the gear case. All of the cover bolts are tight. Can the cam gear be pulled off so the gear case can be removed? Or does the cam have to be pulled from the engine to remove the gear case because there is no way to re-install the cam gear? Thanks for your help.

 

[Cummins12V98]

Did you brake clean the area and check to see the origin of the oil after a few miles?

 

[Ozymandias]

From what I know the cam has to come out.

 

[Grumpy8811]

Have a 2016 3500 C&C with 125000 + miles on it. Oil is leaking from the RF lower corner of the gear case. All of the cover bolts are tight. Can the cam gear be pulled off so the gear case can be removed? Or does the cam have to be pulled from the engine to remove the gear case because there is no way to re-install the cam gear? Thanks for your help.

people have done it.. it isn't EZ but it can be done.. the trick is getting the gear back on the cam.
you search U Tube, you'll probably find a few examples.

I'd clean the heck out of the area before hand and make sure it was a leak I couldn't live with.
oil is cheap.

 

[jmorse]

I have removed the fan, belt and idler tensioner. Cleaned the area. Operated the engine and verified that is where the leak is. The leak is getting worse. I can't stand the oil all over. I scrubbed the area with a tooth brush a brake Kleen. I applied some gasket maker hoping it would seal, but after a week the leak is back. Is the cam gear held on with a bolt? Looking at the Cummins parts diagram I didn't see a bolt. To re-install the gear, I'd need a way to pull it back on. Thanks!

 

[Topzide]

@jmorse, I not sure if it might be worth a try, but when you can get it all cleaned up and allow to sit for a couple of days, then clean it again. After that last cleaning, try some old school Shellac gasket maker. Have cured many an issue with it and use on paper gaskets. This stuff has been used for just metal to metal sealing for a long time. Might be worth a try. Good luck getting it solved.

 

[Grumpy8811]

I have removed the fan, belt and idler tensioner. Cleaned the area. Operated the engine and verified that is where the leak is. The leak is getting worse. I can't stand the oil all over. I scrubbed the area with a tooth brush a brake Kleen. I applied some gasket maker hoping it would seal, but after a week the leak is back. Is the cam gear held on with a bolt? Looking at the Cummins parts diagram I didn't see a bolt. To re-install the gear, I'd need a way to pull it back on. Thanks!

I saw this particular guy on You Tube doing it on a 5.9 take a look..should be similar on a 6.7/ not easy but can be done.

 

[jmorse]

I have looked on another forum and seen just what has to be done. The cam gear needs to be heated for removal and installation. I figured as much. Kind a like replacing a ring gear on a flywheel. I'll watch your video also. Thanks for your help.

 

[lpennock]

Be prepared for the fact you might need a new cover or other work. I had a leak on mine around 17K miles and the dealer wound up putting and new inner cover under warranty.

 

[jmorse]

In the video Grumpy8811 posted, the mistake that guy made was not getting the gear hot enough and not having a toaster oven right by the truck, so installation is quick. Looking on another forum the guy says the gear had to be heated to 450-500 degrees (350 degrees didn't work for him) and it slid right on by hand. He also cooled the camshaft before gear installation. The dealer wants 4k to do this job. I will most likely attempt the repair myself in the next couple of weeks. Thank you lpennock for your input.

 

[Signal73]

There are tools for it as well

https://www.freedomracing.com/3163054-3165093-cummins-camshaft-gear-puller-tool-alt-st-328-b-r.html

 

[wyosteve]

My '18 had the same problem at 36k. Was covered by extended warranty.

 

[Cummins12V98]

On my 350 in my boat I fixed a leak by thoroughly cleaning then applying “The RightStuff”, it worked well.

 

[Diesel85]

On my 350 in my boat I fixed a leak by thoroughly cleaning then applying “The RightStuff”, it worked well.

Just don't do this:

 

[sag2]

Just don't do this:

Wow, that was done by someone who has no idea how to apply RTV. In fact, RTV should not even have been required for that repair.