What is too hot for Aisin trans temp when towing?

[cricha]

17 3500 4x4, Aisin. first time towing with this truck. Long uphill, 8000# trailer, 55-60 mph. 102 air temp. Seeing 225 coolant, 236 oil temp, 175 trans temp. Are these values somewhat normal?

 

[Learjet]

that is about as high as you should see...and that is ok

YES...all normal...enjoy

 

[NIsaacs]

that is about as high as you should see...and that is ok

YES...all normal...enjoy

Do all the new trucks really run that hot on the coolant, 225* on a hard pull? When I see 220 on my '01, I am worried, I don't like it. Cummins says don't go over 230* (old info) but it still might apply. They allow 50hrs a year at 230* but that it is hard on everything, that at those temps the engine will deteriorate sooner. I hit 230* one time, pulling a 2 mile long 6% grade south of Moab, Ut. and my Edge Juice shut me down to limp mode, with a couple of overheating codes that I had to clear.

 

[kthaxton]

Curious if it stayed at 225 on the climb or did it reach 225, then fall, then rise again etc?

 

[Learjet]

you should hear the fan kicking in pretty heavy at those temps and when it does the temps start to fall.

 

[cricha]

temp continued to rise, did not rise and fall. Did not hear the fan come on. I would think the fan would be screaming at 220 coolant temp. The fan normally comes on at 208 coolant temp. Fan will stay on for a short period, then turn off. Tried turning tow/haul on and off to see if there was an influence on the fan operation, no change. When the fan does come on, coolant temp drops fairly quickly, but the oil temp doesn't.

 

[Learjet]

don't worry about the oil temp, it will take care of itself...its cooled by the engine coolant through a heat exchanged behind the oil filter mount

 

[Dieselnerd]

I tow a 15K trailer up long grades in high heat, like pulling out of Laughlin, Nevada heading east. It's one of the grades often used for testing. My coolant never gets that hot. As soon as it gets to about 215 the fan kicks in and it drops back to 195 and then slowly cycles higher until 215 again. Mine has the dual radiators so maybe it cools a little better. You can't miss the fan kicking in, it makes a lot of noise.

 

[Joseph Donnelly]

The oil temp is a calculated value coming out of the ecm. It is an educated guess as to what it probably is.

 

[Cummins12V98]

The oil temp is a calculated value coming out of the ecm. It is an educated guess as to what it probably is.

Is oil pressure a guess also?

 

[Joseph Donnelly]

I have heard from people who should know that oil pressure is also "calculated."

 

[Cummins12V98]

Thanks for the rely Joe!