C-12 Cat need some help!!!

[turbodiesel6_6]

Well i have a C-12 Cat in a Freightliner Columbia, and for the last two months or so we have been adding a gallon of antifreeze every two weeks or so, that equates to about 3500 miles in two weeks, the truck runs in the city and no mtns. It also uses a little oil about a gallon an a half between services witch is about every 14,000 miles. Had an oil sample taken and the lab results cam back with no traces of antifreeze in the oil!!!! So im at a loss on where it is going, all hoses are new and no leaks there , pressure tested the system several times... im thinking head gasket but i just wanna be sure before i tear into the thing..... hopefully some of you here will have some ideas.... and btw... had the oil pan off a couple weeks ago and pressure tested the system then, and had no leaks, i was thinking maybe a liner but appearently not...

[White Duramax]

Stick your finger in the blowby tube and then taste it, yes I'm serious, if it has a sort of sweet taste you are getting antifreeze in the oil. Pull a valve cover off and look to see if is has sludge on the underside of it, this also indicates antifreeze in the oil. I have seen some blow it out the overflow and dry off before you ever see it, you can put the rad. tank overflow tube in a jug and drive it a day and see if any is in it. Also when checking the liners for leaking, we always run the truck until its up to full temp, then drain the oil and pull the pan while its still hot and pressurize the cooling system.

[turbodiesel6_6]

cool i will try that out... never thought i would taste the blow by tube lol... but what the hell..... has there been alot of problems with the C12 head gaskets???

[White Duramax]

Not lots, but we see more Cat head gasket problems than any other engine. It is usually only a bad head gasket if you are blowing coolant out the overflow tube. Coolant in the oil usually is NOT the head gasket.

[turbodiesel6_6]

Ok... no coolant out the overflow tube, no sweet taste.... the only place i have a milky substance is in the fill tube for the oil. Pulled the valve covers off and no sludge there either. I thought maybe the injector cups? But i figured i would have coolant in my fuel, and vice versa.

[White Duramax]

Yea, usually if you have cups leaking you will have fuel in the antifreeze and sometimes starting problems. I would probably just keep running it and keeping a close eye on everything and maybe do another oil sample after some miles.

[lot1954]

at my work every dam cat we have the piston liner seals went out cat had big problems with them. also how are you doing your oil sample we let our trucks sit over the weekend and before we start them monday morning we grab a sample we have the turn valve drain plugs

[dieselbrian]

what year is the truck? if it's new and has egr on it you need to check the egr cooler to se if your burning it. if not check around the head gasket to see if it's leaking externally. to check for a blown haed gasket get a clear plastic bottle put some water in it and put the overflow hose from the coolant tank in it, runthe truck up to temp. see if you have any bubbles in the bottle.

[turbodiesel6_6]

We do oil samples when we are servicing..... every 15000 miles, the truck is a 2000.. so no egr.... i will try the water bottle... i have an empty bottle on it right now... and its not puking it out... we had the oil pan off not to long ago for a pan gasket and did a pressure check and no leaks from the liners that we could tell

[dieselbrian]

do you have access to a chassi dyno ? wish it was a detroit i know alot more about them.