what altitude were you at?
i think higher alt. thinner are truck running hard and hotter

 

I thought you were only seeing spikes to 215?
if so, I wouldn't consider that to be "10F away from engine
damage".

 

what temp are you worried about your HGs? 225F was my "Stay away from" mark, really just gathered from lots of posts of people reporting overheating and engine damage over the last couple years.

 

I had a hose blow off on the 520 floating bridge in Seattle, dumping coolant and saw spikes up to 230 on the ultra gauge while searching for a safe place to pull over. At this point the stock gauge was still in the middle

I'd pull over if my gauge was showing unexpected temperature rises, but if the temperature is going up as the truck works harder, i'd say its working as expected.

I pulled a 4000 pound trailer up over a series of passes on I5 driving back north to Seattle from the OC in my wife's LR4 and there were many times when I had to back off the gas a bit or rev the truck higher than i wanted to. The Lr4 has significantly more power than our Disco's.

 

215F is only 100C and not extraordinary working hard going up mountain roads.

Bearing in mind you mention spikes of 215F not constant and continuously rising. If the system is under pressure, say 1 bar additional or 1 AT, the boiling point is approx 0.5C higher i.e. 105C (wish you guys worked in metric sometimes ). If however you experienced constant temps at 215C whilst running on the flat with slight inclines and undulations there may be cause for concern. As jafir rightly states, work generates heat and hard work generates even more heat but the mean is when you are running at normal or near normal conditions which is the constant. I hit 106C recently in the Pajero after long fastish autoroute cruising when I finally left the autoroute due to the loss of cooling ram air effects. Now that concerned me because the temperature carried on rising and was on my digital gauge unstable, i.e. boiling at the top hose level.

If your truck performs OK under normal conditions I wouldn't be too concerned.

This helps a bit with the explanation of pressure dynamics on fluids. http://en.wikipedia.org/wiki/Boiling_point

 

Thanks for all the input. Seems I may be a bit too paranoid about overheating...reading too many forum horror stories late at night I guess. I'm frankly anxious to try it in hot weather...I'll get my chance here!

 

Forums will do that to a man...You usually only hear about the bad stuff.

 

X1. you never know what or why other people are experiencing bad problems and in some cases they are driving around in an unserviced heap, we call it 'a can of nails' so yep it's easy to get freaked out and paranoid on dedicated forums until you analyse and rationalise some stuff being talked about. It's like the V8 Rover, I've read about blown head gaskets, slipped bore liners, overheating, this oil and that, you name it, **** hapens to them. I'm afraid I wouldn't have a V8 Rover engine as a gift these days (but I did own a 4.0 new one in 2000 .......... but thankfully for a short time ) ...................... I'm a dedicated diesel freak now.

 

Paranoia is only bad if they aren't really out to get you But . . . the one big thing that causes the premature death of Rover V8 engines is overheating. It's a good idea to be cautious.