Muncies came with oil 80/90 rated GL4 Some guys on Chevelle site, have had terrible results with other oils... I found oil, at Car QUEST today.. They do business with AC Delco.. If you want original rated GL4 oil try part # 89021672 Carl2
just sos you know. GM does not make oil. However Petro-Canada has made their oil for many years & Gulf before that. PC's Traxon gearoil line has the GL5 rating now. The GL4 has been superceded years ago. GL4 was a moderate service oil that only had 50% of the extreme pressure additive that is now GL5. Traxon 80/90, 85/140, 75/90 and Synthetic 75/90 all have the GL5 rating and they would all be superior to the GL4. Some may argue that the extra extreme press additive is harder on yellow metals, but I don't think the syncro rings are as big an issue in the Muncie as would be the gear stretch....
My high school buddy "built"my trans, and He asked me to get the "old school" juice I am sure the new stuff is ok, but original is cool lol Carl 2 of 3
-- Edited by 427carl on Wednesday 17th of June 2009 04:18:57 PM