In normal driving, my truck would be pegged at 200 and never move even on a hot day. Since I have had a water pump, hoses, and thermostat, serpentine belt and idler replaced, it runs cooler, maybe 190-195 though its hard to read that gauge precisely. My Ram came with the HD cooling package.

Interestingly, throttle response since these repairs have been done is noticeably better especially in the initial inch of travel of the gas pedal. The truck is much quicker to move than before. This is good and bad as the launch is faster, but I have to watch for tire spin. This was a surprise to me as I didn't think the idler and water pump could be exerting that much drag on the engine. I haven't noticed any change in gas mileage.

Mike

 

Engine runs about 170-180* during normal conditions. While towing its around 190*-205*. When we bought it it ran around 210* but flushing the coolant, 180* thermostat, and a new water pump fixed that. I need to flush the coolant again, and put a new thermostat in, though.

Tranny runs about 150*-160* under normal conditions. While towing it is at 180* Big Flex-a-Lite cooler, and external filter with a WIX filter help a lot.

 

150 seems a little low for the tranny, run it too cold and you can actually cause damage from sludge build up, or so ive been told

 

Well, here is some food for thought: If its 30* outside, and your truck has been sitting for a while, the tranny fluid is also 30*. Anyway, Mopar ATF+4 is synthetic and was made to have great cold-weather flow quality, so I'm not worried about. Plus Purpl is almost always stored in a heated garage, and like I said, all the fluids are synthetic. But I might buy a smaller cooler and put that on in the winter because its gonna take forever to warm up!

 

Doesn't matter where the truck is stored, kept at, or idling at, if it is running to cold,it's running to cold.

 

I know that. Thats why if it is sitting in a 65* garage overnight, the transmission fluid temp will be 65*. Then it shouldnt be getting any colder, even if it is 10* out because the truck is being driven.

 

it does help it stay at a certain temp. exactly in the middle between that first mark and the 210 mark. i'm guessing that its about 160º. it gets up to temp and doesn't budge the whole time its running whether its 100º or 20º outside.