rear

[JOES89K5]

looking to make the change to a 14 bff. what years if any are better ones to get or does it matter. i found one out of a 79 chevy. i already picked up a dana front. i have a rust/rot free 89 k5 in blazer new jersey. thanks

 

[imiceman44]

looking to make the change to a 14 bff. what years if any are better ones to get or does it matter. i found one out of a 79 chevy. i already picked up a dana front. i have a rust/rot free 89 k5 in blazer new jersey. thanks

You will find 2 kinds of 14bff in the earlier years (meaning not a 2000 truck):
there are the big drum brakes and smaller drum brakes. Other than that the difference is gear ratio.
The smaller drums are good with your blazer, you should easily be able to put 15" rims on it.
The 3/4 ton all came with the smaller srums, some of the 1tons too.
Unless you are planning on running huge tires 40+ then go for the bigger drums.

 

[JOES89K5]

i am going to change over to disk brake setup

 

[imiceman44]

i am going to change over to disk brake setup

Then just look for the right gear ratio if you want anything between 3.73 or 4.10 or 4.56 since these came stock and would save you money.
If you are going bigger then just find a clean cheap housing and don't worry about a thing.
One choice though might cost you more but will make it easier for the disc swap, it's the later model, I think it was the 90's and up, the SRW 14bff has the drum outside of the hub, the earlier ones you need to remove the hub to take off the drum and put discs.

 

[BulldogK5]

The spring perches on a 3/4 ton would not have to be relocated whereas the perches on a 1 ton are closer together and must be moved.

 

[imiceman44]

The spring perches on a 3/4 ton would not have to be relocated whereas the perches on a 1 ton are closer together and must be moved.

Or you use 1 ton spring perches with 2 front perches to do a shackle flip.