Oil Coolant and Tranny Temps

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Ratman6161

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Not sure, that's why I'm asking here. I'd imagine there are people out west towing in 75-80mph speed limits. If those temps are normal at that speed, I'd like to know.
Personally I dont see why 3000 RPM would be a problem. The diesel crowd would be horrified but with a gas engine this is normal and expected. I've got a 6.4 + 3.73 in a 2500 so I don't know all the numbers for a 1500/5.7 but that 3.92 is going to have your engine rev higher which is the whole point as it needs to be kept at an RPM where it's got the torque needed for the job you are doing. Peak torque on my 6.4 is at 4000 RPM.

That said, your temp numbers are all noticeably higher than I see with my 6.4 when pulling my 7600 pound travel trailer in summer...but I don't know what's normal for a 5.7.

One thing I'd be concerned about are the tires on your cargo trailer. Do you know their speed rating? I bet you it's less than 75 MPH. Possibly as low as 65 MPH.
 

JRotten98

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Literally driving home from the dealer today after tranny #4. Tranny temp went to 215. Seems high to me at 60mph with no load.
 

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Wild one

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Literally driving home from the dealer today after tranny #4. Tranny temp went to 215. Seems high to me at 60mph with no load.
Do you know if they replaced the Thermal management unit on the side of the transmission? It's where the transmissions thermostat is,and it doesn't come with a replacement transmission,it's been known to have issues,and why it's not included with a new or rebuilt transmission,i haven't quite figured out.If you're on your 4th transmission,it makes me wonder if the thermal management unit might be the common denominator in your case.
 

04fxdwgi

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^^^ What he said.

I pull my boat (6500 including the trailer) behind my '16 1500. Shutters are removed and running 5W30 mobil1, 323 what ever gears. Outside temp last week was 90+, towing between 60 and 65.

Water was 203
oil was same as water
Trans between 170 and 184 consistently

I, personally, won't tow anything above 65 mph. Hard on truck and trailer tires / axle bearings.
 

JRotten98

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Do you know if they replaced the Thermal management unit on the side of the transmission? It's where the transmissions thermostat is,and it doesn't come with a replacement transmission,it's been known to have issues,and why it's not included with a new or rebuilt transmission,i haven't quite figured out.If you're on your 4th transmission,it makes me wonder if the thermal management unit might be the common denominator in your case.
That I do not know...but will inquire! Is it square and mounted on the side and does it require reprogramming? I also read in a thread that some have a valve on one of tranny lines so the tranny warms up quicker however I did not see one on mine.
 

Gero

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I wouldn't worry too much about those temps as long as it doesn't get too much warmer. Gasoline engines rev high to produce its power and a well maintained engine should be able to rev that high all day. Unless you go diesel or force-induction, gas engines will rev high.
 

Wild one

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That I do not know...but will inquire! Is it square and mounted on the side and does it require reprogramming? I also read in a thread that some have a valve on one of tranny lines so the tranny warms up quicker however I did not see one on mine.
The thermal management unit doesn't require reprogramming,it uses a pellet style mechanical thermostat.The thermostat is contained with-in the thermal unit which is the bigger aluminium heat sink block bolted to the drivers side of the transmission. 215 is a bit high for an unloaded truck only doing 60 mph,where you live you could easily get away with one of Caulk04's thermostat bypasses,if he still has any left.
 

CalDad14

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Which transmission is in the OP's truck?

My 17' Ram 1500, 5.7, 6-speed, 392gears; -coolant 204°F
- trans 194°F
- oil pressure 52psi
-oil temp 206°F.

That's towing towing approx. 4000lbs, maxed out on my payload, middle of summer time, four people in cab/running AC. Running @ 68 mph, 5th gear approx. 1900 - 2200 rpm's. Avg. approx. 13 mpg's.

I've never seen my oil temp as high as you posted.
 

JRotten98

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The thermal management unit doesn't require reprogramming,it uses a pellet style mechanical thermostat.The thermostat is contained with-in the thermal unit which is the bigger aluminium heat sink block bolted to the drivers side of the transmission. 215 is a bit high for an unloaded truck only doing 60 mph,where you live you could easily get away with one of Caulk04's thermostat bypasses,if he still has any left.
Something like these:

 

Wild one

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Something like these:

Message Jesse/ Caulk04 on here and see if he has one of his bypasses left,it's far superior to either of those set-ups.The Revmax kit is overpriced and is what CrazyKid and i started with,and ended up basically writing it off. At the time Jesse didn't have his version in production,but it's the easiest to install,and works exceptionally well.
This is CrazyKid and my thread on the Revmax kit,about pg 24 you can see what we ended up doing,in hindsight it's not as good as using Jesse's bypass.

 

JRotten98

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Message Jesse/ Caulk04 on here and see if he has one of his bypasses left,it's far superior to either of those set-ups.The Revmax kit is overpriced and is what CrazyKid and i started with,and ended up basically writing it off. At the time Jesse didn't have his version in production,but it's the easiest to install,and works exceptionally well.
This is CrazyKid and my thread on the Revmax kit,about pg 24 you can see what we ended up doing,in hindsight it's not as good as using Jesse's bypass.

Will it void the warranty though?
 

Wild one

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Will it void the warranty though?
It's about a 1/2 hour job to re-install the factory thermostat,if you end up needing warrenty again.It's far easier to return the truck to stock with Caulk04's bypass,then those other 2 links you posted.
 

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