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Discussion Starter #1
I recently bought 2012 2500 laramie longhorn my issue is seems to run hot when pulling my rv up hills My eng light came on 3/4 up long 10 k hill so pulled over turn around to back to nearest city found a automotive shop which took me in says to replace clutch fan 900 DOLLARS LATER drove after wait 3 days for fan part to come My question now is she runs hot going up same hill got 115 celluis or 235 f i believe after climbing hill the temp cool down to 103 but all hills cause same is this normal ?
 

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235F is high. It should stay below 225F. Fan clutch kicks in about 215-217F and then normally cools things down.

Any cooling system work been done that would have drained the system?
 

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Discussion Starter #3
ok thanks now it is only when climbing large hills im from bc so the highways often enough so maybe should rad system flushed ?thanks longhorn
 

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Depends how heavy are you towing? what is your altitude at the start and at the top?

I know on some of the mountains out there I hit 227-230 But I was grossing nearly 30k lbs making a fair amount of power over stock... But also had an aftermarket turbo... Do you have any other gauges besides factory stuff? Like EGTs, boost?
 

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Discussion Starter #5
Top would be 4000 ft and only towing 6500 lbs trailer loaded and of course my truck loaded too so im thinking 15 k tops but rememember only on the climb only as soon as a level off the temp drop back within a minute back 104 C which is 212F THANKS for input Im going to flush system also maybe symbol as that just stock gauge no after turbo also Longhorn
 

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My 2012 Laramie has only seen 224F once crossing the Teton pass pulling our ~11K travel trailer.

I’d make sure your system is bled and has no air. I can’t imagine a 6500 pound trailer created this issue for you. Your fan should kick on at 217F and keep it pretty steady after that. Is your torque convert locked up when climbing? What speed and gear are you pulling these hills in?
 

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Discussion Starter #7
I M not gearing down just in drive on tow mode should i be gearing down to 6 or 5 when climbing and in tow mode I gear down and use exhaust brake coming down hills thanks for imput Longhorn
 

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It depends on your situation and the speed you are driving. Ideally you want to keep your RPM's up to help. I try not to tow at less than 1500 RPM's in any situation. I like to run between 1600 and 2200 RPM. If I am in hills and the speed is 65 or less, I usually lock 6th gear out to avoid hunting and turning too few RPM's, but again this is situation dependent.
 

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Yeah gearing down to 5th or even 4th will help a lot depending on your speeds... and if running below 65 mph in the mountains I would lock it out of 6th anyways... happy towing with a fair amount of weight would be 1,800 or higher... But yeah making sure the torque converter is locked will reduce temps as well...
 
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