sheriffav8r

WTFO? Came home today and noticed gray sludge puking from my overflow bottle. Antifreeze is now gray sludge through and through. Checked engine oil after running engine and tranny fluid and both are clear. I did notice that the engine was running cool on the drive home but that could have been from the gunk on the thermostat. Are there any possible reasons besides tranny/oil exchanger and heater/block/leak? I have recently changed the oil and replaced the thermostat....

sheriffav8r

Anyone, anyone? I checked the oil and tranny fluid like 5 times and it's still clear. The sludge is the consistancy of mayonnaise and uniformly gray. Took out and checked the thermostat and it opens like it should (I think). Funny thing; I loosened the lower radiator petcock and regular looking antifreeze came dribbling out. Drove the truck with the thermostat out to circulate fluid (along with Prestone Radiator Flush). What can I use to circulate through the system to remove all the gunk? Can I use a low percentage methanol and water mixture to dissolve the stuff?

rattlebox01

You didn't by chance use some type of dexcool/extended life antifreeze when you changed your thermostat did you? I know in my gm trucks that type of antifreeze can cause sludge problems. I just always flush and fill several times to remove it using the prestone also.

sheriffav8r

Nope, didn't add or subtract any fluid. Does anyone know where the oil cooler is? I think it is attached to the oil filter housing....

Midnite

Yup, I think that's the correct location. You might check out Dave Fritz's dodgeram.org site to see if he has any diagrams of the exact location.

I was thinking it might be an oil leak because (and I might be wrong here) I think the oil pressure is higher than the coolant system pressure, and would tend to push the oil into the cooling system instead of the other way around. Your thought of the oil cooler is exactly what came to my mind.

Mike

SIXSLUG

The oil mixture is less dense than water/antifreeze I am guessing, that is why its at the top and your petcock ran clean antifreeze.

I read on here somewhere that somebody ran laundry detergent and water thru the block to clean it up after a mishap like this and others chimed in that it worked pretty well. I'd search this first though.

Sounds like a bad oil cooler to me, if you have no other symptoms.

sheriffav8r

Took it to the shop and they agree: bad oil cooler. Better than a head gasket, but the part from Dodge is $570! Plus 2 gaskets and grommet for an additional $100 or so. Does anyone know the Cummins part number for the oil cooler? The Cummins guy wanted the engine serial number but all I have now is the VIN....

FWIW I tried vinegar, bleach, and methanol separately to try to clean the overflow container with negative results. I bet laundry or dishwasher detergent would work since it is designed to work on oil. I got most of it flushed by removing the thermostat hose and running water into the radiator while the truck was running. That's when I noticed small drops of oil coming up through the water. The oil pressure is, indeed, more than the antifreeze and so it leaked only one way....

Dr.Dizzle

Dishwasher detergent will help clean the system up. I recommend you flush any residual tap water and detergent out with distilled water prior to adding fresh coolant to the system.

BigIron70

Cascade works well to clean oil sludge out of cooling system. Seems like Cummins doesn't want American made parts in their diesel engines anymore. I have changed several of them and they are stamped with the good old communist logo MADE IN CHINA.

sheriffav8r

Cascade, huh? Well, how do I get that big pellet into the cooling system? yuk, yuk, yuk...

BigIron70

They make it in liquid too.

sheriffav8r

Now how long did you have to search for a Cascade .jpeg? The Dodge guys want $570 for the oil cooler piece while the Cummins guys only want $312. So, even with overnighting it and including all the gaskets I will save over $200. That'll buy a little beer....

FWIW, here are the '01.5 oil cooler part numbers and prices:

Oil Cooler (7 fin) 3957544 $312.44
Gasket 4932124 $75
Gasket 3942915 $25 (prices may be switched with above....)
Regulator 3936365 $6.24

sheriffav8r

FWIW, here are some pix of the sludge....

And the oil cooler, 2 gaskets, and pressure relief valve were $380 total at cummins....

sheriffav8r

I tried the Cascade flush and it didn't work. I added some Dawn and it liquified and broke down the sludge most rickey tick. Dawn is the bomb. That, and my truck now has the smoothest hands in town....

SIXSLUG

Dawn: it breaks up the grease, so you don't have tooooooo. Maybe that was for another product.

Glad you gotter cleaned up and running again!