the box said once it gos bad it locks open.i dident like the sound of that but i insalled it anyways
it it garbage or i good deal?

In my opinion this is a good feature for a thermostat to have. Other t-stats will stay closed if they fail and cause you to overheat because the coolant can't get into the engine. With a t-stat that fails open, it will take a little longer for the engine to get up to temp but you won't overheat.

9 out of 10 times any thermostat will not stick closed but rather open. Get a Mopar and change it every time you flush your coolant system, and you'll never have a problem. It's a $10 part...

I bought 2 mopar thermostats and they were both crap. They both said 195*F but neither opened till 208*F.

fail-safe t-stats are crap.

i run stant superstats... no issues. and they get changed every two years.

And that makes them crap? The XJ is designed to run at just under 210 degrees.

Sounds like a "Fail Safe" by Stant, or some variation thereof.

Excellent idea - thermostats usually "fail shut," which leads rapidly to an overheat! I'll take one "failing open" any day of the week and twice on Sunday - if the engine gets stuck running cold, it still runs and you won't warp anything!

any t-stat that i've ever done has either broke and was stuck open, or was stuck open cause the spring got weak... i call BS on these... just a regular Stant will do.. just change them every two years like 93XJLI said..

trudat

good idea.

from my time in tech school (6 years) t-stats fail open, always have.

I have heard of "thermostat sticking" leading to over heating....

seen a few thermostats Fail and not Open........Out of the box new.
I think it can go both ways.

and yes this locking open stat is S#IT