Has anyone checked the temperature of the 11½" cover after a drive unloaded? I've had a noisy rear since day one and STAR refuses to do anything. Well, the 15000 fluid change interval came up so I tried Redline 75w90 oil because I've heard good things about Redline and the manufacturer claims it will reduce oil temps 10º-70ºF. After changing the oil, I can't tell any difference in temperature. It feels about the same as the tranny pan so I'm guessing about 180ºF. This is unloaded after about a 10 mile drive at 65 mph.

I'm going to use a friend's infared thermometer, but this seems high to me. My last truck was a Dakota with the 9¼" axle and even towing a 5000 lb boat I could hold my hand on the cover. Unloaded the cover was at least 50-60ºF cooler then my CTD.

Any feedback is appreciated.

 

I have never check mine unloaded but I have checked it towing my fifth wheel and on a 87 degree F day Outside of Tucson I checked it at 180 degrees with a infra red thermometer.

 

As far as the noisey rear, add some limited slip torque shift stuff or change the fluid to 75w-140 and the noise will go away.
OK stop right there, yes I know DC & AAM say NOT to add anything to the limited slip rear but it gets rid of the chatter

 

I have the Mag-Hytec cover on my F150 with a temp sensor. Last weekend to Tucson & back, it ran 210. Before the Mag-Hytec cover, it ran about 225-230.

I highly recommend the cover: it puts the temp sensor inline with the 'gear-splash', so it gets the hottest oil, it has a dipstick and drain plug. Diff maintenance becomes easier than chaning the engine oil. I also run LE's 75/140 synthetic; always drains clean, whether from my F150 or the Wife's Dakota.

HTH.

Tony

 

My rear diff was starting to make a whine at 15k miles and then I installed a PML cover and use Royal Purple 75w-140. The whine disappeared. I highly recommend using a 75w-140 if you live in the deep south.
As for temps a friend installed a Mag Hytec with a temp probe on his '05 Dually. While pulling a toy trailer through the hill country of Texas last month he saw about 210 degrees. He's running Mobil 1 75w-90.

MikeyB

 

Mikey: how do you like your PML diff cover ? How does it compare to your friends Mag Hytec ? Any idea how much volume it adds to the diff or what it does for temps ?

 

Superduty,
I like the PML cover. I believe it's just as good as the Mag Hytec and $100 cheaper. With the PML I added 5 qts of fluid before it started running out of the level check hole. Can't say what it did for the temps but I'm sure it helps. The paint on the factory cover was already scorched and peeling off.

MikeyB