The first time she overheated into the red. Probably there for a minute or so before I realized it and immediately crossed four lanes to pull over and shut the engine down (while still rolling to a stop!).

Otherwise I never let her passed the high "safe" mark.

 

Dont worry about it.

 

Yeah I have seen engines run very hard in overheat conditions (my brilliant mom drove her land cruiser under overheat conditions until finally the engine seized and shut down!) Surprisingly she still ran after being allowed to cool off...

Don't have any experience with these aluminum rover engines though. I've no idea how much stress they can take before things start going south.

 

Well there was one guy on here a year or so ago with a '03 whos oil pump failed, he drove the truck over 5 miles on the expressway with the oil light staring him in the face before the engine siezed.

 

Ooh that's good to hear. On the subject of oil pumps, I knew a guy at the BMW mechanic I used to go to, said a car came in with the same engine as mine (I was concerned because my oil pressure was low and I thought I might have burnt the valvetrain) complaining that the engine was making funny noises and had been for a few thousand miles. Turns out his ex had poured pond gravel into the oil cap on his new BMW, and he drove around like that for a few months wondering what all the noise was about. Finally the engine failed because the cams ground the gravel into a fine powder which got into the oil pump and seized the bearings! Talk about a strong engine!

Anyway I'm hoping since the engine is all aluminum that under overheat conditions the head and block expand at the same rate, keeping all the seals and whatnot in check. I know aluminum heads on iron blocks have bad hg blows during overheat since they expand at different rates..

 

The problem with overheating a aluminum engine block is the cylinder liners.
Because aluminum is soft they line the cylinder walls with steel sleeves, on a LR engine they are pressed in and they stay in place by pressing out onto the cylinder walls.
When the aluminum expands faster/farther than the steel (because like you said steel and aluminum expand at different rates) one or more liners can drop out of place, at that point you are looking at a rebuild or a new engine.
BUT, you have been driving it since it first overheated, if it had dropped a liner you would know it.

 

Yeah I pretty much ruled out a hg or dropped liner, as the engine still sounds smooth and pulls strong.

 

Might be a little too simple, but could the temp gauge/sensor be failing?

 

Got the truck back from getting the radiator cleaned. The guy said when he pulled it out the space between the radiator and A/C condenser was totally packed with leaves, dandelions, and other crap. He cleaned all that out, thus allowing actual air to flow once again, and also pressure tested and acid cleaned the cores, refilling the unit with yellow prestone per my request (I despise dex-cool). Drove pretty hard on the freeway trying to heat her up and she never did! Today I put about 30 highway miles on her with the A/C blasting and again she cooled herself like a champ. Finally, a resolution to this issue.

As added precaution to these triple digit summer days I am planning on adding a bottle of watter wetter to the coolant once the system is cooled off.

 

Amen my brother!! Dex-Cool is absolute garbage.