Hi Lads, here I go again abusing of your generosity. I saw a document shared in this forum about the coolant flush and thermostat replacement every two years. Since I have to replace the coolant pressure tank for the (apparently) famous leaking (I saw several posts related to that problem). I will also do the coolant flush and thermostat replacement. However there's one for about $13 in AutoZone that I can pick it up today. Then you have several options on Ebay, most of them non oem for about $40 and $50. Then the OEM is between $60 or $70. All the ebay ones arrive in about 2 or 4 days.

The difference between 13 and 60 is not an issue, but if what I get is similar I prefer the one from autozone since I can get it today. Any recommendation? Thanks again!

When I switched out the thermostat towers for my XJ8 and XK8 the whole rig was around $59.00. I doubt they provided an OEM thermostat XJ has been 3 years and the XK 1 year. Just make sure you orient the wiggle pin to the top when installing. The in stock one would be my choice.

I have been using the Gates tsts. from Autozone for years. But be advised that no matter where you buy them there is some variation in opening temperature.

You mean a difference between the ones from Autozone or between the OEM and the Autozone? In that case, is that going to impact negatively in the durability or performance? Thanks!

Howdy Folks:
Back in February of this year, I purchased an identical OE themostat boxed under the CARQUEST label at Advanced Auto. It is steel stamped "WAXSTAT & 84 deg. C" and is made in Great Britain. $13.39 less 2.68 discount plus .72 Tax=$11.43.

The variation I noticed was all with the Gates parts, and it was significant. One of them opened so early that the car would take a half hour to warm up in cold weather. They all started opening at the same temp. but the amount they opened at about 200 deg. was different.

It's been many years since I messed with the thermostat in a car .......but we ALWAYS used to check the opening temp back in the early 70s when I rallied Mini-Coopers. Just get a pot and an accurate thermometer ( don't tell wife you borrowed it from the kitchen ) Chuck the T Stat ( or T stats ) in the pot and start to heat the water and observe when each opens. 2-5 C variation was not uncommon...technology may be better now

I would expect that the more expensive thermostats would have less variance between units.

If not done recently, you are probably better off replacing the entire thermostat tower. On our later cars, the thing is made of plastic, and includes the thermostat, temp sensor, seals and a couple of pipes. The whole thing is a bit more $ than a thermostat alone, but well worth it, in my opinion. Expect about $100 (dealer price!), which, for all the parts provided, is not a bad deal. For perspective, any type of failure in that area leaves you stranded, and you trust 10+ year old plastic at your peril.

Best of luck, keep us posted.

If the OEM thermostat is about 70 and the whole thing is 100, it doesn't seem to be a bad idea. Two questions:
1. Is still easy to replace the tower as replacing the thermostat alone?
2. Do you know what's the part number for my XKR?

Thanks!

I think fmertz may have missed your signature, am sure the tower is metal on our XKRs. I'd go and check mine but the cat (the animal variety) has just taken possession of my lap.

I was clearly speaking for an XK8, and lost track of the original poster talking about an XKR. My mistake.