here's some spring rate info I"ve gathered based on posts here at
. I can't vouch for how accurate this is, but the sources are some of our countries finest citizens:
OEM is supposedly 147 lb/in rate.
Tera 4" TJ coils give 4.5" of lift on an XJ and have a 200 lb/in rate , 20.25" tall unloaded
Tera 3" TJ coils give 3.5" of lift on an XJ and have a 170 lb/in rate
Rusty's 4.5" coils give 5" of lift and have a 150 lb/in rate, 22" tall unloaded
Rustys 3" coils give 3" and have 150 lb/in rate.
RE's 4.5" ZJ coils give 6"-6.25" of lift on an XJ and have a 200 lb/in rate, 22" tall unloaded
RE's 5.5" = 220lbs/in per RE
RE's = 180lbs/in per Dave Nay
RE's ZJ 5.5" = 240lbs/in per Crash
Rancho 3" coils, at least the old coils give about 2 1/4" of lift on an XJ and have a very high 235 lb/in
rate.
Rancho 3" = 240lbs/in per Rancho
Skyjacker 8" = 270lbs/in per Crash
OME coils give 2.25" - 2.5" of lift and have a 148 lb/in rate
OME930 front coils: 160lb/in per Kris Anderson
OMEJC1A rear springs: 148 LB/in per Kris Anderson
OMEJC2A rear springs: 137lb/in with 257lb/in overload spring per Kris Anderson