Cummins isx

I’d think oil getting contaminated is your biggest concern other than plugging dpf.

 

Did you consider replacing the radiator cap? If weak, coolant will get pushed out.

 

I dont do big trucks nor wrenching, but I was curious of this, so I looked a bit.

Here is a 6min video titles "Cummins ISX - OverFlow Full? Spitting out Coolant?".

I did scroll thru the vid and indeed caught a portion about the liner (whatever the hell that is, lol)

It may well have information for you.

 

That year of the ISX it known for sunken liners.. Dealer is more then likely right.

 

Sounds like a liner problem or a cracked head that’s pressurizing your coolant system. Pull the head and see if it’s cracked. If not then liner dropped.

As for how long you can continue to drive it. Who knows. I drove mine for over a month before the shop could get me in for a rebuild. It made it. But if you lose the engine on the road under a load it could be a real pain. Hooks are not cheap and not being able to deliver your load could also cost you some money and reputation.