Dana 300 highway driving operating tempurature

[JeepScrambler]

Those of you with a temp gauge installed on a Dana 300, what sort of temperatures are you seeing with sustained highway driving (over 55 mph for more than 30 miles)? First trip in this Jeep since clocking the transfer case near flat, installing twin sticks, Novak front output shaft, and advance adapters 32 spline rear output & mine got to about 225 after 40 miles or so at 60 mph. Does that sound acceptable? I’ve got a temp sensor installed in the bottom of the pan.

 

[JeepScrambler]

Temp reading after another 40 mile drive.

 

[spankrjs]

I've never monitored the temps, but they will run hot after a rebuild, just like a differential will, until it is "broken" in.

210 doesn't see too hot to me

On long, cross country trips, when I stop for gas, I make it a habit to touch:

1) All four wheel hubs
2) Rear diff
3) transmission
4) transfer case

They will be "warm", but never too hot to touch That is driving at 75-80 mph for 3-4 hours straight

 

[FLCJ8]

Are you running dino or synthetic lubricant?

 

[JeepScrambler]

Sounds like it could very well be the new bearings in the rear output shaft breaking in. The transfer case gets fairly hot to the touch (can only hold my hand on it for a couple seconds, rear aluminum output housing feels slightly warmer than the cast case). I’ve never monitored transfer case temps either with a gauge so wasn’t sure what to expect as far as normal operating temperatures and at what temp. it starts to indicate a problem.

Running just straight 80w-90, non-synthetic oil in it.

 

[spankrjs]

Check the rear output shaft endplay. I installed the same rear output in the tan Scrambler I had. The instructions said the end play was set already. A couple months later, the rear yoke was loose. I would double check the endplay just to be safe.

 

[JeepScrambler]

End play checked out good. I’m just going to run it for a few hundred more miles and keep an eye on it, then do a fluid change. Will see if getting a few more miles on the new bearings will help out the temps.

 

[FLCJ8]

Running just straight 80w-90, non-synthetic oil in it.

It's been reported that synthetic will generate lower operating temperatures.
I don't have any first hand experience with it, but I guess it would make sense if it is in fact "slipperier"

 

[bigwalton]

I'll try to remember to shoot mine with the IR thermometer sometime. No gauge. Same here, it's always nicely warm to the touch but never hot.