Replacing pinion seal on a Dana 80.

[rickf]

Can someone tell me what size socket the pinion nut is on a 98.5 Dana 80 is? I have tried a 1 13/16 and it is a hair small and a 1 7/8 will not fit inside the yoke without grinding the outside of the socket. I am thinking it is metric? Maybe 47mm? Odd size not in most sets.

 

Rick

[rancherman]

yep,   1 7/8ths

 

I  just went and  bought  a  cheapo   socket,   3/4 drive,    to grind  down.  (didn't want to   grind  down  a  S-K   socket!)  If possible,  try to find a  6 point  thinwall socket.   Not  sure  if  there is  such an animal though...

 

methinks  the  torque  is  going to be  460  ft/lbs      I really  recommend  you  holding the   yoke while   breaking loose/tightening.     I  used a  36 inch  pipe wrench  against the  frame.     That way   you aren't going to  be fighting  axle  wrap-up.

Edited May 29, 2014 by rancherman

[Mopar1973Man]

Here is a article on how to do it.

 

http://forum.mopar1973man.com/index.php?/topic/1598-diy-pinion-seal-replacement-dana-80/

 

[diesel4life]

^^^^Gotta love them torque multipliers!^^^^^^

[rickf]

That is a good write up but I am not a fan of impacts on differentials. You are hammering the pinion against the ring and both are hardend gears. I have seen many broken gear sets because of that. I will expend the extra energy to save a grand on a new gear set and the neccesary set up.

Edited May 29, 2014 by rickf

[rancherman]

That is a good write up but I am not a fan of impacts on differentials. You are hammering the pinion against the ring and both are hardend gears. I have seen many broken gear sets because of that. I will expend the extra energy to save a grand on a new gear set and the neccesary set up.

good idea ^^^^  and that's  why  I  use the  pipe wrench.      No  torque  gets  past the yoke..  and   into the  ring and pinion. 

I  usually use the  multiplier on   disassembly,  but  still  use     'straight through'  type  wrenches  for   final  torque...

 

I have  a   1 inch drive   torque wrench,  and  it's handle is plenty long  for  pulling   460..   It  take  2  guys  to  handle  it!

[rickf]

A one ince drive torque wrench! I didn't even have one of them whne I was doing construction equipment work. I always used multipliers or 3/4 drive and doublers. I did have one drive sockets and ratchet though, of coarse back then I could lift it.

[oldbeek]

At one time I had a side business rebuilding Dana differentials. For a seal driver I used exhaust tubing with a soft plug welded on one end and a large washer welded near the other end to get a nice straight drive on the new seal. For a pinion holder I used a 5/16 x 3 inch flat bar 3 ft long. Burned a hole in one end for the largest socket needed and drilled a variety of holes that align with various yokes. This can be bolted directly to the yoke. This gives very good control when removing and torqueing the pinion nut.