GL4 Gear Oil

by Karl von Salzen

All the GL5's you mention are synthetic. If you go to the Amsoil gear oil site you will see it says to use GL5 because it replaces GL2 to GL4, BUT that is ONLY if you use synthetic! READ down further. READ the section on Application. Here, I will post it:

"Application AMSOIL 75W-90, 80W-90 AND 85W-140 Gear Lubes exceed the lubrication and performance requirements for gear boxes where API MT-1, GL-4 or GL-5 lubricants are specified. AMSOIL Synthetic Gear Lubes provide limited slip performance. Although generally not necessary, manufacturers' limited slip additives may be used in conjunction with AMSOIL Synthetic Gear Lube.

After changing a vehicle's limited slip lubricant, drive the vehicle in a tight "figure 8" pattern (lock to lock turns) for a minimum of eight repetitions.

AMSOIL 80W-90 GL-4 Gear Lube is recommended for marine outboard and stern drive lower unit gears and bearings. It is also recommended where the manufacturer specifies GL-4 performance. AMSOIL 80W-90 GL-4 Gear Lube is not recommended as a replacement for API GL-5 products."

READ the last paragragh AGAIN. 80W-90 GL4 IS RECOMMENED WHERE the manufacturer SPECIFIES GL4.

Maybe you think VW never recommended GL4? Again, LEARN to read. Here is the spec sheet FROM VW:

READ the top right corner: Manual transmission: GL4!!!!

Do NOT confuse [you probably will] the FINAL DRIVE of the auto trans THAT uses GL5 with the manual transmission, they are 2 different things.

GL4 is GL4. It NEVER was replaced by GL5 or GL5 with MT1. I still wish I knew where that MT1 mumbo jumbo came from. RE-READ ALL the links I posted the last time this crap came up again.

People, manufacturers RECOMMEND specifications for a reason. Lots of time and research went into it. Not just because one or two people used something else NOT recommended and did not have a problem. Just because Porsche says Swepco is OK in their trans does not mean it is OK in a VW trans. Two TOTALLY different transmissions, internally.

The manufacturer has to stand behind their product, not people that can't read and comprehend. Your choice.....

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