Dana Rear Question - Hot?

[MoparHonda]

My '70 Plymouth GTX has the 3.54 Dana rear. I'm now hearing a clicking, popping noise, sounds like it's coming from the rear, but not sure. It's continous, even when just rolling (clutch in) at low speeds.

Drove the car some 10 miles or so, got it warmed up, sound got louder. Let the car sit for 1/2 hour. Crawled up under the car to see if anything is visibly wrong. The exhaust pipes were cooled down enough to hold, the rear of the transmission was warm. The axle tubes were cool. But the center chunk of the rear was burning hot, too hot to touch for more than a second.

Is it normal for a rear end to get this hot?

(It's full of fluid, I already checked that.)

 

[Jerry Hall]

No, the noise and the heat are telling you something. It's easy enough to look on a Dana, just remove the back cover, drain and inspect. That much heat you should be able to see something out of order. IMO.

 

[Pikser]

Have you done any work on the rear end? Sounds like it may need some lub modifier ?

 

[MoparHonda]

Thank you, Jerry & Pikster.

I bought the car in 2014, never had any problems with the rear, never did anything with the rear other than check the fluid.

Sadly, I'm not a mechanic or rear expert, I probably would not be able to see anything out of order or know what to look for.

 

[Suregrip391]

The Dana in my 67 is freshly built with all new bearings. It gets very hot, like you describe, can’t keep your hand in it for more then a second or two. The wheels in the rear are the same way, I spoke to cass at doctor diff and some others on this board about it, they said that was normal. My 70 Challenger is a lot cooler. The reason mine is hot is because it needs to break in and will loosen up over time. Not sure if yours is a fresh rebuild or not? Mine does not make any noise. All seems good.

 

[MoparHonda]

Thank you, Jerry, Pikster, and SureGrip.

I bought the car in 2014, never had any problems with the rear, never did anything with the rear other than check the fluid. The car was restored in the late 80's, the rear was rebuilt at that time. The car has been driven approximately 25K miles since.

Sadly, I'm not a mechanic or rear expert, I probably would not be able to see anything out of order or know what to look for.

 

[Curiousyellow71]

Rear ends can get hot that is not unusual...but I would be more concerned about the noise. If something is broke in the differential you have metal floating around getting in to the bearings and gears. Its time to jack up the rear and turn it by hand. Wiggle the pinion make sure its tight and doesn't have a bearing going out. Turn the tires by hand listen for noise and feel for tight spots. To diagnose you really don't need much mechanical experience nor is it hard to take off the rear cover and drain the fluid or change the fluid. Taking it apart to set the rear end up if it needs parts takes mechanical experience but don't be afraid of it.

 

[Suregrip391]

I’ve heard of the long bolts that hold both halves of the powerlok case coming loose and backing out if loctite was not used when assembling and torquing down. Those are the types of things you can look for once the cover is off.

 

[dadsbee]

Put a thermo gun on it... 165/175F seems to be about normal on both of my cars.