i have recently installed a rearend temp gauge,it runs a little warm in my opinion.not bad when mty,about 150.but start putting some weght on it and it starts getting a little warm.10000 lbs load runs about 180,but a 24000 lbs load and it will run up to about 210.just in case anyone was interested how hot there diff might be getting.i am running syn in diff.

I tried one of those in my wifes rearend. SAME RESULTS - empty, the rear runs at normal temp - but as soon and you put something large in it the temp goes right up. But as we all know that is because the rear is NEW to this and once it breaks in will have no problems with the more than normal "cargo" :lol: :lol: :lol:

I tried one of those in my wifes rearend. SAME RESULTS - empty, the rear runs at normal temp - but as soon and you put something large in it the temp goes right up. But as we all know that is because the rear is NEW to this and once it breaks in will have no problems with the more than normal "cargo" :lol: :lol: :lol:

Michael...you might want to edit your comment. I doubt your wife would appreciate it!!!!:muahaha:

MaxRock

I tried one of those in my wifes rearend. SAME RESULTS - empty, the rear runs at normal temp - but as soon and you put something large in it the temp goes right up. But as we all know that is because the rear is NEW to this and once it breaks in will have no problems with the more than normal "cargo" :lol: :lol: :lol:
Thats funny if you have a sick mind like I do.

There is no wife - thought it would sound better than saying girlfriend:lol: :lol: :lol: .

Was just to easy so I had to comment.

I tried one of those in my wifes rearend. SAME RESULTS - empty, the rear runs at normal temp - but as soon and you put something large in it the temp goes right up. But as we all know that is because the rear is NEW to this and once it breaks in will have no problems with the more than normal "cargo" :lol: :lol: :lol:
:funnypost

i have recently installed a rearend temp gauge,it runs a little warm in my opinion.not bad when mty,about 150.but start putting some weght on it and it starts getting a little warm.10000 lbs load runs about 180,but a 24000 lbs load and it will run up to about 210.just in case anyone was interested how hot there diff might be getting.i am running syn in diff.

All cuteness and girlfriends aside, 210 is just fine for synthetic oil, actually it's fine for motor oil as well...

ok,now i have just come back from a missouri to colorado across i-70 trip to grand junction the over to salt lake city then back across i-80 then back to missouri.rearend temps got as high as 250 loaded with a 20000 lb load.came back from salt lake mty temps still ran 230 all day long.as far as they break in comment my truck has over 70000 miles on it now i think it is broke in.

Those temps you are seeing is likely why GM spec's synthetic diff fluid. Synthetic can handle 250, but you should change it on the severe duty interval (I believe that's every 25k miles). And if you really are bothered by it, change it more often.

I tend to fall on that "safety margin" side of things myself, so I'll be doing mine every 15k or so. As they say "cheap insurance"...

I thought 98.6 was the aceptable temp and anything over that was indication of something wrong?

Seriously though. Wonder if a aftermarket cover would add a bit of cooling? Probably at lest(with the greater capacity) keep the fluid in better shape. Thats alot of cabbage though.....

are you running the 75 90 or the thicker stuff?

I guess I wasn't thinking those temps were out of line, more whether or not the oil could handle 'em... I don't think I've ever had a diff run that cool !! To be honest. When I changed my diff oil for the 1st time, I had driven the truck around, no load, no hard driving, and the pumpkin was too hot to touch -- I had to wait til it cooled some before I changed the oil out even...

So is body temp really the operating spec for one of these diffs, or is that just a general rule of thumb? (or was that 98.6 C ??) :rolleyes:

Heh, I think the 98.6 rearend temp went along with the "wife rearend" comment. Heh.

Kids these days... :rolleyes:

Just remember to always check the oil from your wifes rear. If you much SLUDGE build up that can cause extra friction. In turn slowing things down and possibly turning messy.

Rule of thumb : clean dipstck = smooth going
:lol: :lol: :lol: :lol: