C20 Dana 60 Wheel Bearing Grease or Gear Oil?

[Big Kev-O]

When I was rebuilding my drum brakes on my Dana 60 Axle I found lots of greasy crud all over underneath the drum. I figured the outer hub seal needed to be replaced so I pulled the hub, replaced the seal, cleaned & greased the bearings and bolted it all back up. When I was sliding the axle (full float) back in I realized there is no axle seal to keep the gear oil inside the axle tubes. After a few Google search I read that floating Dana 60s do not have axle shaft seals, the bearings do not get greased and the gear oil lubricates the bearings.

Do the bearings get greased or lubed by the gear oil? The gear oil thing seams kind of strange to me because if the truck is traveling on a flat surface for an extended distance how is oil supposed to migrate all the way down the axle tube to keep the bearing lubed?

[Wrenchbender Ret]

As long as the grease in the rear end is kept full or near full, enough grease flows to the wheel brgs. when the truck leans or goes around corners the grease is fed to the brgs. Some grease is stored in the hub to the level of the axle. I serviced these for 60 years & never had a failure as long as the rear end had enough grease & the brgs were adjusted correctly. Coat the brgs. with gear lube & fill the hub up to the seal & it will work fine. Older models had slingers on the end of the hub that would send any grease that leaked by the seal out to the tire instead of in the brake drum. Modern seals installed correctly don't need these.
George

[Big Kev-O]

Thanks Wrenchbender.

I just found some instructions from Spicer that suggested to lightly grease the bearings when installing to provide lubrication until the gear oil from the center can flow over into the hub. I hope the new seals keep everything contained.

[mr.mud1]

that's exactly what i did,while doing the rear brakes on my truck with a Dana 60.i greased the bearings when i installed them but once it's running,and when the gear oil is full,the bearings get lubed with gear oil.the big trucks i drove for years,do the same thing,the hubs run in gear oil and they go lots of miles trouble free,as long as you keep an eye on the lube level.take care.Greg

[kwmech]

Just don't forget to check the oil level after the first drive around as it will drop after filling the tubes and hubs.

[special-K]

^^^ This. And grease is good as an assembly lube on bearings. On front drive axles it's all lubed by gear oil, too, but outside the steering knuckles it's pack bearings with grease, same as 2wd. Then, with lock-out hubs, it's back to oil. Not even gear oil, just simple motor oil is good. Outside the bearings turns with the hub, so lube is only needed to keep moving parts moving freely from 'free' to 'lock'. Many a lockout dial has been damaged when bearing grease made them stubborn

[72c20customcamper]

When I put new bearings in my 68 I did it as per the manual . Lightly pack the bearing with grease . It keeps the bearing from being starved until the gear oil moves around to the bearings . I also parked the truck on a steep grade in my lawn so that one side was down hill then turned the truck around to get the gear oil into the tubes .