Dang it! I tell ya'll, its ALWAYS SOMETHING when you least expect it. Been driving the Jimmy (01 SLE) with no immediate problems. I was going to change the oil today since I have no idea what the previous owner did. Got side tracted with my father in law needing a ride. I ran the ac a few times when I 1st got the Jimmy but not much since then. He asks to turn it on. Ok no problem. We have it on for a bout 15 - 20 minutes during some hwy driving, I get off the hwy and smell that oh so familiar coolant smell with a hint of smoke from the driver side of my hood. I IMMEDIATELY pull over and pop the hood. Radiators hissing and spitting coolant from the driver side section of the radiator. I wait till it cools off and start pouring water in the radiator since I have no available coolant. As I open the cap, the radiator cap is full of gunk and rusty puddy along with the inside of the radiator looking like you poured water into a rusty cup. Previous owner SWEARS he flushed it, but it doesnt seem like it. I also felt the passenger side radiator hose and it was cool, making me think that the t stat needs to be changed. Then when I drove it back home and checked again, it was warm. On the ride home the gauge went past half but never overheated like it did before but its still was doing some light hissing. What should my plan of attack be? Ive got a few gallons of coolant and prestone radiator flush with flush kit. I also picked up a new t stat. What do yall think?

 

Run it on water till you see if you have a crack in the radiator. No reason to dump coolant 2X's if you have to change it.

 

+1, sounds like you're on the right track though. Hopefully all the sludge won't plug up the water pump or heater core.

 

Yeah that sounds plugged up...flush it out with the old garden hose and see if you can get it to run clean...but yeah +1 on running water for awhile.

 

Much obliged fellas! The drain plug is on the passenger side, when Im flushing the radiator, should I leave the plug open and do I need to jack the Jimmy up r can it be reached w/o the jack?

 

Dead on as my crosshairs on a raccoon in my trash can! Filled up the radiator as much as it could until I turned on the car and filled it till it kept spilling out of the top. I saw some bubbling on the driver side radiator core. It was so small, it turned out to be a hair line crack from the top side row of the end caps to maybe the 2nd or 3rd row. I mean it is THIN. I think between its lack of up keep before I got the Jimmy and a week of me driving it and turning on the ac here and there probably gave it time to drain low and eventually over heat, but Im not sure because yesterday was the longest I had the ac on since owning the Jimmy an thats when it all happened. I NEVER saw any leaks before this time, well hell Im getting old lol, there may have been some spotting but never payed it any mind because of the size. Mind you, since I got it I never topped off the radiator because I never got signs of it needing it and never topped off the reservoir because it was at the full mark. So what do yall think lead up to the overheat yesterday based on the info above?

P.S. The drain plug looks like you have to stick a dang screw driver with a flat head the size of a butter knife to turn it lol. Did he break that sucker or did the 01s have different plugs than the other models with the ready turn tabs?

Yall been real good to me on this issue, if anyones near me in the carolina area or ever come thru, drinks on me!

 

Sounds like it got busted and he just stuck what-ever kind of plug he could find that fit. Overheat sounds like a combo-pack of stuff coming together at the same time.

 

It may be a cheap replacement radiator without an actual drain plug. Saw a few of these on different types of GM vehicles while I worked at the dealership.

 

^

This. I went ahead and paid for a new radiator and had it installed along with a new thermostat, pcv valve and radiator cap. All seems good now. Thanks to Precision Car Care. I preciate all the responses that aided in the repair of the Jimmy. NOW to make this sucker a lil quicker on the draw!