So I got a block heater installed in December...loved it through the winter months. About a week or so after initial install...the heater blew out and leaked coolant everywhere. This happened when I was merging into traffic and getting on the throttle pretty good. The shop reinstalled and tightened it down again and I drove it like that until Sunday...never romping the throttle again to test (didn't have time to deal with it leaking if it popped again). So Sunday I took it for some spirited driving and sure enough she started leaking again.

Has anyone had this issue with block heaters and if so what brand of block heater cured the issue or is there something else that is causing this?

The shop claims to do block heaters all the time without issue and I don't see how a 5k rpm push is too much for the heater to handle.

Also if it isn't apparent...this is a 4.0L and the freeze plug type heater.

 

Anyone have any experience with this?

 

It happens occasionally. If you aren't having cooling system problems then the heater isn't correct, or isn't installed correctly. Personally I'd put a plug back in and run a tank heater in the lower hose.