You can probsbly find something close on the shelf at Piggly WigglyScrew this. I'm hitting Amazon to find CA oil.
Unless an OEM goes back and Revises Previous Standards….. they previous ones Remain “Current”.You lik we to create and fight straw men
Tell me where you can get the recommendecd CC diesel engine oil.
NOWHERE
Tell me where you can get a certified GL-4 gear oil
NOWHERE.
So what you do is use the CURRENT standards. Is that too complex for you to grasp?
Dan
I have explained this multiple times There is no way to test and certify an oil as GL-4. Its obsolete and the prjmary test equipment (new factory prepared Dodge truck axles) are long gone.. You have no idea whats in any of those "Gl-4" oils or how they perform. API no longer recognizes any claim of GL'4 performance.Dan, there’s a thing known as “Google”….and if you go there and type-in “GL-4 gear Oil”…you’ll get Dozens of sources.
gl-4 gear oil for sale
Here’s only three:
I have explained this multiple times There is no way to test and certify an oil as GL-4. Its obsolete and the prjmary test equipment (new factory prepared Dodge truck axles) are long gone.. You have no idea whats in any of those "Gl-4" oils or how they perform. API no longer recognizes any claim of GL'4 performance.
GL-5 oils ars actually tested, certified., snd recognized by API.
You might want to ask the sellers of those GL-4 oils your liability question. I doubt you will find one that will accept liability in any specific application. Thats becayse yhey can't backup their GL-4 claim with a ASTM STP 512A certification test report. All they csn say is they deem it equivalent in most applications. I can show you beaucoup certified GL-5 products that make that same claim. And BTW - the oil you linked is actually a GL-5 oil
Now if want to get technical we can look at the now obsolete STP 512A test requirements for GL-4 and GL-5 service. What you will see is the only difference is the wear tests. GL-5 out performs GL-4 and thats why API never updated the requirements tests for GL-4.

From my latest round of questions to AMSOIL Technical Services on the GL-4 to GL-5 compatibility with Kubota axle and gear oil "recommendations", I wish that I was equipped with the information that we have now on this firecracker of a great thread. I just may when we ever get an rainy day here in the deep South, call them back up and see if they will send me a copy of that acknowledgement of the compatibility from Kubota as they kept refering to in my questioning. I'll bet that it will be a miracle if they send something to me on that, but if they do I'll post it here for sure.I have explained this multiple times There is no way to test and certify an oil as GL-4. Its obsolete and the prjmary test equipment (new factory prepared Dodge truck axles) are long gone.. You have no idea whats in any of those "Gl-4" oils or how they perform. API no longer recognizes any claim of GL'4 performance.
GL-5 oils ars actually tested, certified., snd recognized by API.
You might want to ask the sellers of those GL-4 oils your liability question. I doubt you will find one that will accept liability in any specific application. Thats becayse yhey can't backup their GL-4 claim with a ASTM STP 512A certification test report. All they csn say is they deem it equivalent in most applications. I can show you beaucoup certified GL-5 products that make that same claim. And BTW - the oil you linked is actually a GL-5 oil
Now if want to get technical we can look at the now obsolete STP 512A test requirements for GL-4 and GL-5 service. What you will see is the only difference is the wear tests. GL-5 out performs GL-4 and thats why API never updated the requirements tests for GL-4.
That’s a fair point. GL-4 is an old specification, and the lack of current standardized testing makes it difficult to compare modern oils based on a “GL-4” label alone. For anyone choosing an oil today, it makes sense to look at the manufacturer’s specific requirements and the oil’s documented test data rather than relying solely on the GL rating.From my latest round of questions to AMSOIL Technical Services on the GL-4 to GL-5 compatibility with Kubota axle and gear oil "recommendations", I wish that I was equipped with the information that we have now on this firecracker of a great thread. I just may when we ever get an rainy day here in the deep South, call them back up and see if they will send me a copy of that acknowledgement of the compatibility from Kubota as they kept refering to in my questioning. I'll bet that it will be a miracle if they send something to me on that, but if they do I'll post it here for sure.
In the meanTime, the GL-5 in the ZD mower gearbox is running like a champ, even in this heat, and to some degree I think it's running cooler and there is a little less venting off of the pressure vent valve compared to the GL-4 lube oil. I'm keeping my eye on this one close as this will help a lot of good folks out there trying to make that informed decision. I know that this really helped me despite the fact that I have been messing with oils and lubricants in all kinds of heavy manchery my entire life. Get it wrong and you will pay the hefty price though!
Eric