Coolant Leak

[tufcj]

Got home from an errand yesterday, and when I stepped out of the truck, I got the unmistakable smell of anti-freeze. Sure enough, it's dripping on the driveway.

Let it cool and looked this morning. I see wetness below the PS pump, on the crossmember, and left lower a-arm. It's not leaking cold, only when hot. Hasn't been leaking long, the surge tank is still full. What would you think was the most likely source, thermostat crossover? Water pump?

It's a 2003 LB7 with 130K on it.

Thanks,

Bob
tufcj

[rapidoxidationman]

If you're lucky it's just a loose clamp somewhere. Get a decent inspection mirror, flashlight, and a rag and start looking...

I just went through several gallons of Dex (mainly because I was lazy and didn't spend the time looking for the slow leak) then got sick of mixing new batches every couple of weeks. Found a loose clamp on the hose to the surge tank. Cost about $1.00 for a new quality pipe clamp from Napa.

On the up side, I've got fresh coolant in my system now :)

[More Power]

Check the surge tank after an overnight shutdown. If it's still holding pressure, you may... may need to consider an overpressure problem with the cooling system - that can result in a coolant leak at a hose connection like rapidoxidationman suggested.

This happened to me due to a head gasket/cup leak...

Jim