It's 110 days today in the CA desert. I drove the 2003 xk8 to coffee at 87 degrees at 8 am and home before ten at 99. Just my limit for running with the top down when the sun not yet searing. Had to wait for several long lights and back ups for 10 mins and 5 min respectively and all was normal. Not running the air (when I do it's totally cool!) and I really won't bring her out and use the air during the hottest hours. Any thoughts on running at what temps? Still a new owner after 9 months with no problems except replacing the battery and getting a tender for it based on many offerings of advice from this great group. Happy Summer.

 

My 2002 XKR is driven every day regardless
of the temperature.

I’m in NE Oklahoma where summers routinely get to 105-115 F in July and August. And I take 2 or 3 summer trips to visit daughter and Dr’s in central Texas. It’s a rare trip if I don’t see 110 F while sitting in traffic in Austin or Dallas.

i have an aftermarket gauge that’s connected to the OBD-II port. So continuously monitoring coolant and oil temp is my normal.

Depending on the cars speed, my summertime coolant normal temp 190 F to 205 F, with sometimes going up a little higher if traffic has me sitting at zero MPH.

going higher than 80 mph always brings down the coolant temp.


oil temp is a constant 16 to 20 degrees F higher than the coolant temp.

if you are concerned about high engine temperatures, I recommend using a quality synthetic oil. They handle higher heat more successfully than conventional oil. Mobil 1 0w-40 is working very well for me.

Z

 

I agree, since my first one in 1999, I use only Mobil1 0W-40 in all my modern cars, two of these were turbodiesels and covered 400000km each with no issues and still the original turbocharger. My only doubt was that it is the wrong gradient for my cars which, like the XKR, are designed for a 5W-30, but despite this, all runs like new.

 

my owners manual specifies several different viscosities of oil that are appropriate, each depending on the general ambient air temperature.

for my climate the 0w-40 is listed as correct (see attached photo).

Z

 

The jag is more tolerant.. Other car I have has a sticker under the bonnet "5w-30 viscosity only"

 

—ANOTHER HACK—
DON’T READ IF YOU HAVE A WEAK STOMACH

what do you think would happen if you disregarded the sticker ?

I live on the edge, and have found the sky is not falling when I fudge the manufacturer’s recommendations and use one oil for several different vehicles. I’m just not going to stock 5 different oils :

"One oil to rule them all, One oil to lube them, One oil to bring them all and in the darkness bind them."



I have one car asks for 5w-20. Another one 5w-30, and yet another’s owner manual says (the XKR) it’s satisfied with a variety of oils. And then there’s the Honda lawnmower. I can’t even begin to guess the proper oil for it.

Yet they all have been stone cold reliable and not at all lacking for the proper and expected performance. Despite, or maybe because of, the steady diet of Mobil 1 0w-40 for years and tens of thousands of miles.

 

I cannot beleive you lot still mess about with deg F and ounces but having said that the only way to keep it cool is to fit a 82 deg C thermostat and run the fans at half speed 24/7. Easy on a 97 ...one wire to earth . More brain required on later models.
The real problem is that the water pump does not run fast enough at idle ....if you go to neutral and raise the revs the temp drops fast .If can find a pulley thats 100mm rather than 110 that will work great.
Look on ebay for a p10 head up display for about $30 plugs into OBD and tells you everything.