- Aug 10, 2003
- College Dorm...
I can't find help anywhere else, so hopefully someone here will have an idea. I have a NV4500 transmission that calls for a 75w or 80w-90 GL-4 lubricant. As far as I know, the NV4500 needs a GL-4 lube for a few reasons: At high temperatures, phosphorous plates out and reduces the coefficient of friction of the synchronizer rings. Since there is twice the amount of sulfur/phosphorous in GL-5 lubes, there is a higher detrimental effect. Also, the same additive package can attack "light" metals at higher temperatures. Why would Pennzoil Synchromesh not be good in this application? Synchromesh: http://www.pzlqs.com/Tech/Pdsheet/DomesticMarketing/Gear&Transmission/pdf/SynchromeshFluid.PDF GL-4's: http://www.pzlqs.com/Tech/Pdsheet/DomesticMarketing/Gear&Transmission/pdf/GearplusSAE80W90GL-4.PDF http://www.pzlqs.com/Tech/Pdsheet/DomesticMarketing/Gear&Transmission/pdf/SyntheticSAE75W90GL-4.PDF http://www.pzlqs.com/Tech/Pdsheet/QuakerState/Gear&Transmission/pdf/MultiPurposeGL-4GearLubricants.PDF Seems the main difference is that the Synchromesh is thinner... Thanks for any help guys. [ October 12, 2004, 03:43 PM: Message edited by: Jelly ]