I am looking for a rear end for my 1982 F150 (XLT Lariet Explorer, 4.9 straight 6, reg cab, long bed, F151 which means it has a heavier rear end on it) I need a 9" with 3:55 gears. My question is, what years should I look for as I am looking around for one? Will they already have 31 splines on the axles? I actually only need the housing with the axle tubes and axles but will likely have to buy the whole set up I just dont know enough about these to be certain Im buying the right one. Thank you!

 

You had better pull an axle to double check, but all trucks with the 9 inch had 31 splines I believe
Just about any truck or Bronco with a 9" should be the same and work
Call a junkyard and ask them about which models will swap and they will know possibly more

 

Will all 9" housings fit the multiple gear ratios?

 

Yes, the housing is the same, it's the carrier that is different with different ratios
So,
if you have a 2.75 and want to go to a 4.10 you need a different carrier IIRR

 

Perfect. How do I read the tag on the differential as far as the year goes? Thats the only part I couldn't find info on.
Also, what do I look for when buying a used one, possible damage etc.

 

The numbers cast into the center section should tell you the year but you will have to look up how to read them
Roughly
C9 for 69, C8 for 68, D1 for 71. B is the 50s E0TZ is a 1980 truck part
DOZZ is a 1970 Mustang part
F parts are the 90's
There are parts people on here that know that stuff backwards and forwards
There is a good article by H.A.M.B Jalopy Journal about identifying 9 inch ford rear ends
Google identifying 9 inch ford rear ends and it will come up

 

You want a big bearing 31 spline 9 inch axle like the 1/2 ton trucks (like yours) had a few years prior to yours
That HAMB site will show you how to identify one at the junkyard
Generally, the axle tubes will get bigger on the outside ends and not smaller or stay the same size if it is a big bearing housing
You can tell 31 or 28 spline by looking at the ends of the axles themselves.
Good luck
Most all trucks if not all have 31 spline big bearing axles

 

What have I got here?

 

That K146 means something as per the date of manufacture
Maybe November 14th 1966
Look at that HAMB site