Threaded Mode | Linear Mode

Dmurphy16 · 08-28-2025, **(Subject: 2010 isx burning coolant? )**

I’ve got a 2010 t800 with a Cummins isx. Bought the truck a few months ago but it’s been sitting. Finally getting around to getting it roadworthy. Took it out for a short ride about 20 min. While driving it was puffing white smoke, and the coolant level alarm came on. When I got back the coolant reservoir was empty, so I added 2.5 gallons or so. Took it for a ride again and same thing. Coolant is getting into the exhaust and being burnt. from some quick research it can be many things; head gasket dropped liner, egr cooler.
Service records show the truck has had coolant loss issues in the past, it’s been pressure tested, no loss, ruled out internal/external leak. Radiator has been replaced.
I am thinking it’s possibly EGR cooler? I would like to start trying to diagnose so I can figure out if it is the cooler I can send it to the mechanic to replace it, but know it won’t be cheap.
any suggestions?

tree98 · 08-28-2025, **(Subject: 2010 isx burning coolant? )**

Pressure test the cooling system to 20 psi and look for external leaks, also disconnect the egr cooler so you can see inside it for leaks. If you don't see anything you'll have to drop the oil pan so you can look for leaks from a dropped liner or leaking injector cup.
Don't assume there's no leaks because someone else says so, verify it yourself.
Using that much coolant should be easy to find it.

hhow55 · 08-28-2025, **(Subject: 2010 isx burning coolant? )**

Very well could also be the aftertreatment fuel injector is leaking coolant, or an injector o-ring or injector sleeve is damaged.........Quickserve.cummins.com has info on how to properly diagnose these potential problems.

Dmurphy16

(08-28-2025 )hhow55 Wrote: Very well could also be the aftertreatment fuel injector is leaking coolant, or an injector o-ring or injector sleeve is damaged.........Quickserve.cummins.com has info on how to properly diagnose these potential problems.

I don’t have the tools or the knowledgeable to tackle it myself. I’d rather have someone that knows what they are doing look at it. With that being said, what are the chances it’s not and egr cooler and it’s worse? The truck runs fine otherwise. It was off the road for a bit, I put the coolant in, went for the ride and noticed it was gone and am assuming it burned it (due to the white cloud behind me) I haven’t touched the truck since then but want to now so trying to come up with a plan to see if it’d worth putting money into.

mikkhh

Well it is not easy to find somebody knowledgeable to do those things nowadays, most "mechanics" have even less experience and knowledge than you have. Instead of paying somebody else to learn on your equipment you should tackle things yourself and learn yourself.

Dropped liner(s) and cracked head is very common on high mileage isx. How many miles this truck has? 800 000? When and if it has been overhauled?

What shape is the rest of the truck? No rust? How much use it is going to get? Farm use? OTR long haul truck?

Rawze

Coolant in the engine and oil system destroys engines at a rapid pace.. your still on this several months later??.

STOP DRIVING IT AND FIND YOUR COOLANT ISSUES!!!>>>>

info: https://rawze.com/forums/showthread.php?...6#pid75706
and... https://rawze.com/forums/showthread.php?...1#pid84511