The GL4 is for the Muncies and Borg Warners etc. It has to do with the "yellow metals" in the transmission. The newer transmissions like the Tremec call for the ATF which is a GL5 oil.
<span style="font-weight: bold">Click Here</span>
<span style="font-weight: bold">Click Here</span>
I sell a lot of this GL4 AMSOIL to hotrodders locally as well as the Cummins truck guys using the NV4500 transmission. I swapped it into my stuff a few years ago and noticed a big difference. I am a dealer and will be happy to help if anyone needs some shipped or you can just use my referral # 2011844 to knock a few bucks off the price.
Tommy [img]<<GRAEMLIN_URL>>/
[/img]