Rear axle coil perch angle

[SomeMidwesternGuy]

I'm in the process of re-gearing and locking my 99 TJ's axles. I currently have them out and have a buddy doing the work. The rear coil perches were rusted through and I have new ones coming in. I'm planning on putting them slightly forward of where they were so they're closer to level while using the SYE adapter. I'm going to sandblast and powdercoat the axles, so I would like to weld everything up prior. That said, does anyone know about how far forward I would need to move them? I have a 3.5 short arm lift going on it when it's all said and done. I'm sure it's impossible to give a super specific answer, but I'd be crazy grateful for even a ballpark idea. Thanks a lot to anyone who might know!

 

[jjvw]

Look at the top of the frame arch and find the hole. That is center of the arch. Put the spring seats center in the arch. From there, make sure the upper and lower bump stops line up at full shock compression. You can also trim and adjust the spring seat to change the ride height, if desired.

That is the super specific answer.

 

[SomeMidwesternGuy]

Thanks a ton for the reply! Is there any possible way to figure get it done with the axles in a separate location? If not, I suppose it wouldn't be too awful to just grind off the powdercoating where the coil perches end up going and then adding paint. Especially since it'll mostly be covered by the perches.

 

[jjvw]

I haven't moved spring seats without being able to confirm the final ride height with the springs installed before the finish welding.

 

[SomeMidwesternGuy]

And that makes perfect sense. I guess it's good to just confirm that's what I need to do. Thanks for the information on how to do it right!

 

[NskLJ]

And that makes perfect sense. I guess it's good to just confirm that's what I need to do. Thanks for the information on how to do it right!

are you replacing the spring perches on the axle or frame?

 

[SomeMidwesternGuy]

are you replacing the spring perches on the axle or frame?

I'm actually replacing both, but this question is geared towards the perches on the axle. Sorry for the confusion!

 

[NskLJ]

I'm actually replacing both, but this question is geared towards the perches on the axle. Sorry for the confusion!

I would put those in the stock location and relocate the uppers so the bump stops contact each other squarely. As described by @jjvw

 

[sierradmax]

careful rotating frame buckets back. You can only go so far before the track bar mount comes into play.