GL-4 is a grade of gear oil, GL-5 is the other common grade:
http://www.4crawler.com/4x4/4R_TechInfo.shtml#Fluids

Hey Mike,

You asked me to message you when I got the part numbers...

I posted the part numbers for what I got, and also made some suggestions on other part numbers... rest is here:
https://www.yotatech.com/forums/f116...nstall-167979/

Good luck, and let me know if you need any help!

Well I am selling them off for $200 (+ship for you) thats for all four corners 4" Pro comp all spring lift.
no shocks. <<I can include the rears though for another $50>>
no steering correction. <<will need a high steer or Pro comp drop 4" - 7" drag link>>
no brake line correction. <<may not need cut the brackets off frame
no drive line correction. <<I have a cheesy 2" spacer for $30>>
no rear brake proportion valve correction <<make one out of flat bar>>
no pinion angle correction shims << I will include one shim the other one is broken and lost I ran it without no biggie>>
One good thng about these springs is you can use the OEM u-bolts & shackles they are only 3 leaf packs.

HEY but you live in California I am in Washington It may be a grip to go postal but I can check it out on the slow boat, But I would do a paypal transaction only