I'm reading everywhere here that the stock temp. gauge is basically useless as it stays @ mid level until it's too late. I was wondering does anyone know a more efficient replacement that will fit without having to modify the gauge cluster drastically if so let me know. I'm putting my newly acquired XJ8L in the shop this week to flush all the fluids & check out some things to make sure she's right.

Thanks

This has been mentioned on here many times.
There is a gent on here who offers a product called 'Real Gauge'
Try surfing the archives ;o)

Here you go RealGauge FAQ - TheJagWrangler

Yea I searched prior to posting only to pull up over 700 threads w/ no real answer lol.

Thanks that appears to be spot on !

BTW, at least on the MY 2002, I disagree with the contentionthat the guage is useless. I had an overheat due to a sudden coolant loss ( I smelled it but thought it was the car next to me!), and the guage indeed climbed out ot the middle. I got the car stopped and patched the hose, refilled it with water, and drove it home. That was 100,000 miles ago and the car showed no ill effects since.

The guage is not much good at reading actual tmperature, but it will indicate hot or cold. With a real guage (or a RealGuage) you can monitor the engine temperature for longer term diagnostic reasons, but the OEM guage will keep you from buning up the motor. But, you have to monitor it and the idiot light. Once the cooolant is gone, ther is nothing but engine block heat to heat the temparature sensor for the guage, whether you have a Real Guage" or not.

And I fully understand the Jaguar (or Ford, I suppose) engineer's thinking in doing the temperature scale like they did after reading some comments posted about temperature!. A car engine is designed to run best in a fairly narrow range of temperatures. Hotter can kill it quick, and cooler will loose efficiency and can sludge it up due to not "boiling" the condensation water out of the crankcase. But, the engine temperature will vary some due to engine load, ambient temperature, AC load and vehicle speed, and that's OK.