Ok looks like I will be driving like this from now on. I installed a clear hose from TS to RAD with the hose capped off, when jeep is cold, the hose filled up with coolant but did get to temperature. I would assume this should only happen when the TS is open. I bought a new Thermostat (this is the 3rd replacement), did the hose test, same thing. I installed everything the way it should be yet still not getting up to temperature with the yet again new thermostat. This is my first and last GM vehicle, I am gong back to German engineering. Am i missing something? does anything need to be done with the new thermostat prior to installation? some sort of calibration?

My trick for getting heat in cold weather was to put it in 4wd, lock out the overdrive, and drive like a maniac for a few minutes. Being plugged in and/or warming it up for a long time never gave heat. Blocking airflow to the radiator didn't improve anything so I gave up on that.

I've got TURBO-DIESEL-FREAK's thermostat installed but I haven't finished putting the jeep back together yet to try it out due to medical issues but I'm looking forward to heat without the maniacal driving.

"Webasto TSL17 diesel powered engine coolant heater"

If you can find one, discontinued is all I get.

"Webasto TSL17 diesel powered engine coolant heater"

If you can find one, discontinued is all I get.

xsfpns: You could be dealing with more than one problem.

These are words of wisdom. Be prepared to heed them and go down the rabbit hole of, "just how much of the cooling system am I going to need to replace, anyway?"

When we bought our CRD a little over two years ago, I drove it 1300 miles home with what I thought was just a crappy fan clutch. Replaced (and upgraded) that, and things were a little better.

It then became obvious that a previous owner had mixed non-HOAT coolant with the HOAT coolant the CRD requires. As a result, the radiator was toast. Flushed the hell out of the engine, replaced the radiator, and things were noticeably better.

Then the weather got cold, and the KJ couldn't get up to temperature. The thermostat was shot. Replaced it with an HDS thermostat, and I finally had a properly-working cooling system. It's been perfectly fine ever since.

Don't trust the factory thermostats; they're crap. And if you're thinking of gutting the internals of one followed by going the inline
route, that's risking head gasket failure.


What he said!

I have two CRDs. One of the first repairs / mods completed on both was HDS001 thermostats. Never looked back nor regretted the expense. One of my CRDs has over 200000 miles use on the HDS001. Been driven across the continent three times in winter weather. No issues.

Your call, but the number of right ways to do this is very small while there are a great many ways to screw it all up horribly.