1 ton 14 bolt swap into GMC sierra help?!?!

tyler togonon

New Member
i found a 1 ton 14 bolt on CL that is cheaper than re gearing my stock 10 bolt. it came off of a 1991 chevy. what will i need to do to fit it into my 2006 sierra. will it need different brake line fittings? longer brake lines? are the spring perches in the same place? will i need a different drive shaft?

has anyone done this before and will it be worth it? i just need it to last me until i go 4 linked with a fabricated housing



Well-Known Member
I did this a few years ago: 14 bolt axle advice needed
The 1 ton = 10.5" full floater, it's worth it IMO. Not a direct swap though.
The 3/4 ton 9.5" SF just needs your 10-bolt pinion yoke and to have 6 lug everything.

Cliffs notes my FF swap:
-Needs 6 on 5.5 hubs machined or purchased
-Use 99-04 1500 rear calipers, rotors, brake line
-Open centerbore of rotors to 4.25"ish
-Turn down axle shaft drive flanges to 4.25"ish
-Machine drive flange bolts to fit within 4.25" circle when installed - start with 1/2-13 sockets
-Move leaf spring pads
-Mount calipers
-Pinion length is the same as 10-bolt
-Check existing u-joint size, use 1350 or Neapco 2-1153