axle swap pinion agle

[scott soucy]

I'm replacing the 12 bolt in my '77 Jimmy with a 14b sf from a '97 2wd 3/4 ton. I've never done an axle swap, but I've been doing alot of research on how its done and think I can handle it, except one thing. I do know that the 14 b needs the spring pads,shock mounts relocated, so what i need to know is, can I asume the pinion angle is the same even though the 14b is much larger. Is this a stupid question,am I over thinking this? Has anybody done this same swap? I was hoping to get the angle set and pads welded on without puting the axle under the truck and then taking it off,and putting it back again to check angle. I'm pretty much working on this by myself and the fewer times I need to move the axle the better. Any help or insight would be helpful.
Thanks All

 

[HOPPER]

Im pretty sure that a 3/4 sf will bolt right up with no mods. Have you measured the perch location on both axles to verify?

 

[jonrpick]

Im pretty sure that a 3/4 sf will bolt right up with no mods. Have you measured the perch location on both axles to verify?

Yeah, but it's from a '97. I'm pretty sure the spring perch location changed in the 90's. Correct me if I'm wrong.

 

[scott soucy]

Yes, they do need to be moved. Theres a few inch difference. And the shock mounts hang waaaay to low.

 

[driney]

Although I set my angle with the axle under the truck, I don't see why it wouldn't be the same as the 12 bolt if you are not modifying the suspension. Some day when it's nice I think I'll try to compare my 14 bolt and my old 10 bolt. Maybe you've got the shock mounts figured out, but I was able to modify the mounts from the 14 bolt after I cut them off to fit up high like the ones off my 10 bolt.

 

[carpeonnel]

yeah, I cut the shock mounts off on mine cuz they hung so low. I got some radiused shock tabs from Kert and welded them on and they worked great. I wasn't gonna do it but the stock shock mounts hang so low that once I had my K5 sitting at the height I wanted they didn't make the pro-comp shocks I wanted long enough.

 

[scott soucy]

Thanks for the input. The angle that I came up with on the 12b was about 15 degrees, with 4" lift. Does that sound familiar to anyone?