Finally got around to doing this, thought it would be a good reference for everyone. So, without farther ado, here are all the codes I can think of. (Feel free to add)
PYB- Pennzoil conventional
PP- Pennzoil Platinum
PG- Pennzoil Gold
PU- Pennzoil Ultra
Quaker State Conventional- Quaker State Green Bottle
Quaker State Advanced Durability - Quaker State Advanced Durability
QSUD- Quaker State Ultimate Durability
Quaker State High Mileage- Quaker State High Mileage
QSED- Quaker State Enhanced Durability
VWB- Valvoline conventional
VML- Valvoline MaxLife
VSN- Valvoline SynPower
VNG- Valvoline NexGen
RTS- Rotella T6
RTF- Rotella T5
RLI- Renewable Lubricants, Inc.
DS- (Havoline) Deposit Shield
ST- SuperTech
XG- Extended Guard
P1- Purolator Pure 1
RP- Royal Purple
SSO- Signature Series (Amsoil)
XL- Extended Life (Amsoil)
OE- Original Equipment (Amsoil)
Add any you can think of!
PYB- Pennzoil conventional
PP- Pennzoil Platinum
PG- Pennzoil Gold
PU- Pennzoil Ultra
Quaker State Conventional- Quaker State Green Bottle
Quaker State Advanced Durability - Quaker State Advanced Durability
QSUD- Quaker State Ultimate Durability
Quaker State High Mileage- Quaker State High Mileage
QSED- Quaker State Enhanced Durability
VWB- Valvoline conventional
VML- Valvoline MaxLife
VSN- Valvoline SynPower
VNG- Valvoline NexGen
RTS- Rotella T6
RTF- Rotella T5
RLI- Renewable Lubricants, Inc.
DS- (Havoline) Deposit Shield
ST- SuperTech
XG- Extended Guard
P1- Purolator Pure 1
RP- Royal Purple
SSO- Signature Series (Amsoil)
XL- Extended Life (Amsoil)
OE- Original Equipment (Amsoil)
Add any you can think of!