Axel shaft hot

Afternoon peeps!

Just came back from a little trip in the dart and noticed that passenger side rear axel shaft was ROASTING hot.

The drum was cool so ruled out a brake binding issue

Driver side was cool as a cucumber, passenger side super hot. Couldn't even touch it.

Only thing I've done recently is new lug nuts but can't see that causing it.

Wanna have some sort of idea where to start before I look into it.

What we think? Bearings maybe?

They are the timkin tapered type.

70 dart
8.75 suregrip axel, 489 case 3.55 gearing. Standard length a body SBP halfshafts (all tho housing was narrowed from a b body)

Thanks!

Sam.