Engine/Transmission (1998.5 - 2002) coolant leak

[dnesbitt3]

Hopefully someone can guide me in the right direction. I have a very small coolant leak where the upper radiator hose returns to the block. It seems to be leaking under the metal elbow where it attached to the block (I'm assuming the thermosdat is located there) Thermosdat was replaced last winter (by dealer) and leak didn't appear until cooler weather this year. 3 bolts seem tight (I was afraid to really lay into them). Any ideas?? Is there supposed to be a gasket between the elbow and the block?



Your help is appreciated.



Peace,

Don



99 2500 Stock, 2WD, 3:54 rear-end, Tommy Lift, 170,000 miles

 

[chrleb1]

You might want to take a real close look at it. If it is right by the thermostat elbow, but not leaking from that gasket you have a problem. A lot of people have been finding the same problem. It could be your head gasket. This happened to one of our trucks, it appeared to be the housing, but turned out to be the head gasket. The gasket is not very wide right at that point you described.

 

[B.G. Smith]

There is a rubber seal around the top flange of the thermostat which is supposed to seal the joint. I doubt that the seal is available seperately, if it is bad enough to be a problem I would drain the coolant below the thermostat level, remove the flange and maybe use some silicone sealant on the seal. bg.