Block Heater

[12vkaleb]

I plugged my 94 in and before i walked away i heard something kick on and sounded like it was boiling the oil. I know it keeps the oil warm but it sounded unhealthy lol. Its prolly normal but i never heard it on any other truck.

[Lower]

It keeps the antifreeze warm, if you plug it in as soon as you stop driving it will make that sound

[12vkaleb]

Haha my bad, but i heard it last night and over looked it unil this morning when i came out and it ws still doing it. The only reason im asking is bcz somebody put a different cord on it and it was an extension cord lol. I wouldnt have gave it a second thought if it wasnt or this.

[cloper91]

My '95 does this same thing. Doesn't matter if I plug it in right after driving it or if I plug it in 3 hrs later. It sounds like it is boiling the coolant. I have never had any problems so I just ignore it.

[illflem]

It's the coolant slightly boiling around the heater element.
Both my trucks have done it since brand new
My electric hot water heater does it too