Ok, I have been using search buttons looking at different spring info. In my findings, I see this (see below) posted alot. I have some questions about it.


Front Springs
Prod# Code Service #
14029399 BZY 14029399 | (+) Highest load rate
14029398 BZX 14029398 |
14029397 BZW 14029398 |
14029396 CDB 14029396 |
14029395 BXY 14029396 |
14029396 BXX 14029396 | (-) Lowest load rate


Rear Springs
Prod# Code Service #
10018083 NNB 10018092 | (+) Highest load rate
10018092 NNM 10018092 |
10018091 NNL 10018091 |
10018093 NNN 10018091 |
10032969 NYB 10018091 | (-) Lowest load rate

How can a coil with a "different" load rating (according to NNL codes) have the same part number?

Also, has anyone lowered their car using stock gm parts?? If so, did you end up cutting your coils??

Also, I called GM dealer, they gave me a rear spring number of 10305134 with a code of NVX. Anyone know where this plays in at??