530RL
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Does Lucas make a true API GL4 gear oil and where can I get it?
All Lucas gear oils are gl4 and gl5 approved.
Appreciate the response.
If they are approved for both, they will not be good for synchro mesh transmissions with yellow metals. My wallet now knows this.
One of the additives that make them API GL5 is in simple terms an anti slip or limited slip which is great for everything modern but my problem is with 60's and 70's manual boxes that have a lot of yellow metals in them.
I do really appreciate you checking. :thumbsup
I do make that they are safe for yellow metals. I will have Lucas oil respond in here and explain. During one of my visits to the lab they were showing me this.
That would certainly be good information from Lucas, I would like to hear their position on the subject, especially for all of the sandrail owners since the majority (Mendeola 2D, "E-box", Weddle HV-1, all VW) of synchromesh transaxles are VW based and still use VW brass synchros.
At Weddle, we will recommend GL-5 oil in a race car that will get serviced at least once a year with synchros getting replaced regularly. We will tend to recommend GL-4 oils for most "recreationally" driven sandrails and play cars as most people want to extend the time between services as much as possible. But that all depends on the driver, someone who wants to drive their car like a race car in the dunes, should understand that racecar transmissions and transaxles get serviced at least once a year, instead of every 4-5 seasons. There is generally less protection with GL-4 oils to the gear faces, depending on how the car is driven, it can be a non-issue.
The difference between the 2 variations is the "Extreme Pressure" additives. GL-5 has more of these additives that protect the faces of the gears under extreme loads, but it has been found that most GL-5 rated oils will break down yellow metals (brass synchronizers) and cause them to crack or just plain disintegrate.
Added: You wouldn't want to use any type of "Moly" oil as synchronizers depend on friction to speed up or slow down the gear during the shift. We have had many complaints about not being able to shift, and many times it comes back using Moly oils. Moly oils work great in dogchange sequential boxes like Albins sequential, Mendeola/PBS S4/5, Mendeola S4D/5D.
Here is the issue. Our product says that it is API GL-4 and API GL-5. However, it is not recommended for syncromesh applications because a special fluid needs to be used due to different frictional properties and presence of yellow metals. If the gear oil is going to be used in applications where there are no yellow metals and API GL-4 fluid is recommended then there is no issue. Bottom line is do not use our gear oils in syncromesh applications.
Best Regards,
Mark Negast
Lucas Oil Products
Technical Director