The leaf springs will give a lift depending on spring arch and length.

You buy leaf springs based on the amount of lift you desire.

I mean you need springs for a 4" lift. A 4" thick pack could give varying amount of lift... depending on length and arch.

Consider driveline angles....

Yes, when you start lifting a vehicle by suspension, you need to compensate by dropping the t-case. You should lonly need a 1/2 inch to 1" drop (spacer between the t-case mounting and frame).

You will be a lot happier with no driveline vibration to destroy u-joints....

John Stewart
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