Are these “normal” operating temperatures?

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HangmanNY

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Location
New York State
Ram Year
2015
Engine
5.7L Hemi
I have a 2015 Ram 1500 with the 5.7l hemi and the ZF 8HP70 transmission. Just over 90,000 miles.

I did both differentials fluid changes with Redline fluids, transfer case with Amsoil MV atf. I also removed the Mopar factory transmission pan and put the PPE pan in. I went with the Valvoline MaxLife. I did a second and third “drain and refills” to get as much new fluid into the transmission.

Also changed the motor oil with Mobil 1 5W-20 and Mobil 1 filter.

I also did a complete drain of the cooling system. then I removed the old thermostat, cleaned both surfaces, and put the rubber O-ring back in place, then bolted the thermostat housing back. Filled with distilled water and a quart of “flush”. Drove for @ 80 minutes, drained again. Filled again with distilled water and drove for 15 minutes, drained again.

I put a new Mopar 203° Thermostat in. I put 2 gallons of fresh OAT coolant concentrate (to mix with the 2 gallons of remaining distilled water in the block).

Today I ran the truck for about an hour at @ 65 MPH. These are my operating temperatures. Are these readings normal? We are currently in Florida.

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Burla

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Ram Year
2010 Hemi Reg Cab 4x4
Engine
Hemi
I have the same numbers except for my oil witch is 235. Is that too high ? Oil is PUP 20/30.
I start worrying about oil temp at 250/255f, I havent seen those but if I did I would pull over and idle temps down. Mind you the largest risk is cooling, as in if you are that hot and it is cold outside, you have a larger risk of cooling metal then degradation of oil. If you are the worrying type, you can switch to redline, a combo of line 2 and 5 in this chart, esters and pao can operate hotter, just facts, your oil is line 1 mineral oil.

I use redline but for a different reason, this is just a side bonus. I would have no worries with your oil at 235f, but you may want to bring temps down a bit before just turning off engine if it is winter time, summer you should be ok, no matter what oil you use redline wont help cooling metal surfaces. If you were constantly at 235f, I might consider a shorter interval as well, under 5k miles. Oil does shear easier with temp, thus why they measure shear at temps and call it hths or high temperature high shear testing. Here is the thing in your favor, 5w20 is shear stable anyhow and 235 isnt that hot for shearing, so it isnt a big deal, I'm just more careful then most and usually make the safe plays.

I would say if I had shutters, I'd do the shutter delete, that should get your temps down. 2010 didnt have shutters, which is why I never see 235f even in hot temps towing.

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Burla

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2010 Hemi Reg Cab 4x4
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Hemi
When it comes to coolant, I only see 206 as the highest I remember, if I saw that go up I would change my thermostat to a 180. That should never see 235 in a gas engine. Even though coolant does boil til like 260 if it runs hot the engine oil will climb super high over time.

2 easy solutions, shutter delete and cooler thermo stats, easy if someone wants to drop temps. rfe easy to delete thermo bypass valve, the 8 speed a little more difficult but it is posted around here.
 
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