Coolant disappearing

[LwnmwnMan2]

2006 Dodge Ram 2500 Cummins diesel.

Coolant has disappeared twice now.

It's not an external leak, no spot on the ground, no signs in the engine compartment of a leaky hose, bad gasket.

Truck has 3900 miles on it.

Took it into the dealer, they said "no puddles on the ground, no signs of leaks anywhere". I said, yes, I know.

They put dye in the coolant so it would show up under black light, I drove it for 3 days, took it back, no signs of leaks again.

Its got a bad fan clutch, so that's been ordered.

The first time the coolant disappeared, it wsa New Year's eve, 2 am while plowing. Limped the truck home, filled the coolant, then it was good for a couple of weeks.

It doesn't slowly diappear. All of a sudden a week ago, the coolant was gone again, almost like someone syphons it out. It's gone in both the radiator and the overflow tank.

I've got a record on file at the dealer, so now I'm just driving it again until the coolant disappears again.

My dad and I are both thinking it's a bad head gasket, or a bad head itself, with a manu. flaw from the factory.

Any other ideas?? We pretty much believe it's an internal leak somewhere.

[john.wells]

Quote:

---

My 2000 Dodge Ram quad 4x4 with the 5.9 is doing the same thing. I can smell antifreeze but never see any drips or wetness. And my recovery bottle is always being emptied. I just had the water pump and thermostat replaced this summer.

---

You could have a pinhole in a hose that basically atomizes the coolant with no real visible leaking. I just replaced my water pump a short time ago, and I had the same issue. When I pulled my water pump off, I found the by-pass hose was ready to explode, but still had enough integrity to pass a pressure test. I was going through coolant at a rate of about a 1/2 gallon a week, and could smell it after shutting down from a good drive, but no leaks that I could find. The bypass hose is buried under aluminum bulkhead that carries your alternator and A/C compressor, so until my water pump crapped out, I could never see where my problem was. This was in my 99 ram with a 360 gasoline engine (5.9L). Hope this helps.

[LwnmwnMan2]

Quote:

---

Quote:

---

My 2000 Dodge Ram quad 4x4 with the 5.9 is doing the same thing. I can smell antifreeze but never see any drips or wetness. And my recovery bottle is always being emptied. I just had the water pump and thermostat replaced this summer.

---

You could have a pinhole in a hose that basically atomizes the coolant with no real visible leaking. I just replaced my water pump a short time ago, and I had the same issue. When I pulled my water pump off, I found the by-pass hose was ready to explode, but still had enough integrity to pass a pressure test. I was going through coolant at a rate of about a 1/2 gallon a week, and could smell it after shutting down from a good drive, but no leaks that I could find. The bypass hose is buried under aluminum bulkhead that carries your alternator and A/C compressor, so until my water pump crapped out, I could never see where my problem was. This was in my 99 ram with a 360 gasoline engine (5.9L). Hope this helps.

---

I think this is basically what was happening with my spring clamp that was bad. It was still good enough to pass the pressure test, but as soon as I put the plow on and started running around at 70 mph, that the engine built up enough pressure that it would start leaking out, the reason that the coolant would disappear when I was plowing.