Losing coolant

[Welderman85]

Hello all i recently started driving my 2000 tahoe alot more than normal. Today my low coolant light came on. I thought it was weird and have never had an issue with it before but I stopped and got some and filled the reservior checked the oil dipstick for milky oil and continued on. Once it got home I checked it and the reservoir was low again. I didn't smell anything when it was running and I don't notice leaking from anywhere. But the lipstick and under the oil cap are still clean. Im not sure how to find out where it is all going. Thanks

 

[justirv]

Hello all i recently started driving my 2000 tahoe alot more than normal. Today my low coolant light came on. I thought it was weird and have never had an issue with it before but I stopped and got some and filled the reservior checked the oil dipstick for milky oil and continued on. Once it got home I checked it and the reservoir was low again. I didn't smell anything when it was running and I don't notice leaking from anywhere. But the lipstick and under the oil cap are still clean. Im not sure how to find out where it is all going. Thanks

I'd check the weep hole at the water-pump. Also the transmission dipstick, just to be sure (internal radiator leak). Coolant hose connectors at the firewall are notoriously brittle, and if you have rear air, that whole path. I got a relatively inexpensive pressure tester off AMZ that helped me locate issues fairly quickly.

 

[Scottydoggs]

water pump could be leaking, sometimes they leak after you park it and walk away, sometimes they leak all the time. heater hoses where they meet the fire wall also do a slow leak to the point you never notice till the heater is ice cold unless its rev'ed up some or driving.

 

[Fless]

All good suggestions so far. Watch for traces of coolant from the water pump weep hole, as well as the plastic tees on the firewall that go to the heater core -- and rear heat if you have it. Coolant can dry but usually it leaves some kind of trace.

Rent a cooling system pressure test kit from your local auto parts store, pressurize the system and look for leakdown.

I tend to check the surge tank level when the engine is cold; that way the cool fluid hasn't expanded. Being consistent with where (relatively flat surface) and when (cold) will show the most consistent readings.