'11 Pete 386 w/ an ISX using coolant.

So from the research Ive done, Im fairly certain I know the answer but I want to see if there's something I missed.

The engine is a '13 Cummins RECON with just over 500k on it. Truck has been using coolant since I started running it. It has gotten worse in the last several thousand miles/2wks. Before anyone says egr cooler, its not because of reasons we cant talk about here. There is no visible evidence of it leaking anywhere. So this leads me to believe its going through the cyl's and out the exhaust. And the only way that is possible is due to 1 or more slipped liners, correct?

So is there any way for me to test this theory before putting it back into the shop?

If it is a slipped liner(s), at 500k what is my best route for fixing the issue? I have a trusted shop that will do any work, but I want to look at any and all options. Fix existing engine, replace with known good used shortblock or longblock? I dont think new will be in the budget, even though its a company truck, they will just opt to cut their losses and put me in another truck (not what I want).

 

Egr cooler is still in place, just no way for coolant to flow through it.

I didnt know the doser valve had coolant flowing to it. There's some evidence to indicate coolants coming out of the stacks because of some black soot on the sleeper.

Im actually sitting in the truck now here at my house and its been off since 8pm last night. I can actually smell what seems to be burnt coolant.

The other thing Ive noticed is a random hard start. Like the batteries are low and it wont turn the engine over, but they check good and more often than not, the engine will fire right off. I was thinking this might be a sign of coolant in a cyl.

 

I know head gaskets dont always cause an overheating issue, but this truck runs exactly as it should, according to the guage anyway. Big hills it'll run upto 205, fan kicks on and it'll drop back down to 185 and stay between there and 195 when rolling down a flat road. Even in the Tx summers.

Ive never been a fan of any kind of coolant stop leak products. Especially on a $30k engine lol.

 

Yea...about that stuff...my exhaust is restriction free.

 

So I just bobtailed to pick up my trailer and in 14mi it used approx 1/2 gallon of coolant. I came back home and sure it enough it sucked down another 1/2 gal.

A quick convo with a friend/former boss and who owns a heavy truck repair shop said we can guess all night, but he is pretty confident its a slipped liner.