ok on my 96 jeep cherokee my coolant temp sending unit is on the driver side by the firewall. i need to change it but there is only a nut left of it and it is rounded down. how can i get this out. i cant use pliers or anything bc of the tight spot

 

PB blaster, Then take a smaller socket and pound it on there.

 

sears sells a "bolt-out" socket that cuts into a damaged bolt/nut