Overheating Issue During Steep Uphill Climbs

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batboy

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Jan 8, 2013
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Location
Fredericksburg VA
Ram Year
2001
Engine
5.9L Turbo Diesel
I did a quick search with no success, so I thought I would ask the question. Do any of you have the same problem?

I recently went on a road trip that took me across the Appalachians. There are some pretty steep interstate hills. Speed limit on the roads is 70 and I was maintaining a speed around 75. When trying to go up the steep hills (7% grade), the truck would start to overheat. To be specific, the truck would not gear down until it lost significant speed. Once it geared down and accelerated, while still going up the hill, the water temperature would rapidly increase into the red zone and the idiot light would come on (check gauges). Only when I would reduce the speed, regardless of gear, would the temperature go back down. This happened twice. I was not towing anything. I did have a few hundred pounds of gear in the bed, but nothing ridiculous.

The truck is a 2001, 2500 diesel, extended cab, standard bed, about 170k miles. I was in 2WD of course.

So, is this normal? Are diesels just not meant to go fast up hills? Is this a turbo thing (turbo getting too hot)? Could my truck need a tune-up? Would an intercooler help or any other add on? I'm obviously concerned that if I were towing something it would have been much worse.

Thanks for your tips and advice. I am a diesel newbie, so I apologize in advance is this is a common thing.
 

Power247

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High Point, NC
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6.4 HEMI
My truck is a '12 so it's tough to compare but I have been up the Appalachian mountains to Asheville NC many times and never overheated. It sounds to me like the cooling system needs serviced or possibly something may be on its way out. Try the easy things first like blowing out the radiator with compressed air, that was something we did with our International bucket trucks before we too them up the mountain. Blow from the engine side out the grill if possible. Changing the thermostat is a cheap endeavor if that hasn't been done yet. Last would be a coolant flush but with the age of the truck I would be prepared to buy a new radiator too. Who knows what the flush will break apart.

Greg
2012 | RAM 2500 | CCSB | Custom tuned by Double R Diesel
2016 | Heartland Pioneer | DS310
 
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batboy

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Jan 8, 2013
Posts
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Location
Fredericksburg VA
Ram Year
2001
Engine
5.9L Turbo Diesel
Thanks for the tips. I was going to try some of those options but wanted to see if this was actually a problem or something that was normal for diesels. Sounds like maybe it is not common and there may be a problem.
 

CTD

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Location
Southwest, VA
Ram Year
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5.7 Hemi
I did a quick search with no success, so I thought I would ask the question. Do any of you have the same problem?

I recently went on a road trip that took me across the Appalachians. There are some pretty steep interstate hills. Speed limit on the roads is 70 and I was maintaining a speed around 75. When trying to go up the steep hills (7% grade), the truck would start to overheat. To be specific, the truck would not gear down until it lost significant speed. Once it geared down and accelerated, while still going up the hill, the water temperature would rapidly increase into the red zone and the idiot light would come on (check gauges). Only when I would reduce the speed, regardless of gear, would the temperature go back down. This happened twice. I was not towing anything. I did have a few hundred pounds of gear in the bed, but nothing ridiculous.

The truck is a 2001, 2500 diesel, extended cab, standard bed, about 170k miles. I was in 2WD of course.

So, is this normal? Are diesels just not meant to go fast up hills? Is this a turbo thing (turbo getting too hot)? Could my truck need a tune-up? Would an intercooler help or any other add on? I'm obviously concerned that if I were towing something it would have been much worse.

Thanks for your tips and advice. I am a diesel newbie, so I apologize in advance is this is a common thing.

Like power247 said check the simple things first. First thing I would do is replace the thermostat and than go from there. Make sure your fan Is kicking on, your fan clutch could have went bad. Check your coolant and make sure there is no oil in the coolant and check your oil to make sure there is no coolant in the oil, It's possible to have a leaking head gasket, but lets hope that's not the case, but these model trucks are notorious for this when they get some age on them. If not then fire it up take rad cap off and see if you can see coolant moving if little or no movement water pump it probably shot. If nothing shows there use a good air tool and thoroughly cleaned your radiator. They will get packed full of dirt and bugs. If still nothing flush your system to see if that is the cause. Make sure you get all the air purged from system after you flush. Are you getting any lag and how much boost are you getting. A bad turbo or leaky intake system can also contribute to over heating. The combination or the two would make it worse.Take the inlet tube off of the turbo and see if you have any play in the shaft. Pinch the nut in your fingers and move it side to side and in and out there should not be a lot of movement. Also look for any oil in this area. Hope this helps some.
 
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