First, the FORD M2C-134D and M4864-A/B oils are no longer serviced, meaning no longer made/supplied by Case New Holland. They prefer to sell their newer Boomer model tractors and synthetic oil products rather than help keep the millions of vintage Ford models still being used. Besides, the FORD name has been gone completely since the early 1990?s. You aren?t getting any exclusive parts at a CNH dealer ?they use the same suppliers as everyone else now as it's been for decades. For most applications, straight GL-1 SAE 90 Gear Oil works just fine in all conditions. NAPA sells it in bulk 5 gallon buckets, and TSC sells the same stuff in 2 gallon jugs. The verbiage ?Specially Formulated For Old Ford Tractors? is simply a marketing technique.
NH AMBRA BRAND MC2-134D OIL ?NO LONGER SERVICED:
NAPA API GL-1 SAE-90 OIL:
TSC TRAVELLER BRAND SAE-GL-1 90:
-Tim Daley(MI)
Here is the best explanation on hydraulic oil that TOH has written about many times and can be found in the archives:
The Ford tractor oil sold at TSC is nothing more than SAE 90 GL-1 gear oil. That is as generic as it gets and about the lowest performing gear oil you can buy today. The N-series owner's manual specifies M4864A/B tractor oil. That was the 1940 Ford specification for industry standard SAE 80 a 90 mild EP gear oil. In the current world that would be most nearly approximated by a GL4 gear oil. Putting "specially formulated for old Ford tractors" on the label of the generic GL-1 gear oil is nothing more than marketing hype aimed at people who will believe anything they see on a label. It is the lowest performing gear oil you could possibly choose for your tractor and not what Ford recommended during N-series production.
As I said before - in today's world there is nothing special about the 50+ year old M2C-134D specification or the Ambra Multi-G 134 oil that CNH was selling. That specification is just an old OEM specification for what is now industry standard and inexpensive Universal Tractor Transmission Fluid (UTTF). Kubota has one they call UDT, JD has HyGard, and CNH now has HyTran which is their newest formulation that replaces MasterTran and Multi-G 134 in most of their applications. They are all virtually identical UTTF products. Fundamentally UTTF is nothing more than a high viscosity index, mild EP, SAE 80 grade gear oil with GL-4 level performance.
In some specific "state of the art" type applications the OEM formulations are very carefully tailored to the peculiar friction requirements of the OEM design and generic formulations may not provide the same level of performance. Limited slip differentials, viscous drives, and hydrostatic and synchromesh manual transmissions are some examples of where the OEM oils MAY be a better choice. A 60+ year old N-series tractor is not one of those applications.
In a nutshell my recommendation is use any good quality UTTF, avoid low end UTTF's (the "303" branded stuff in particular), and if you want to use a gear oil avoid mono-grade GL-1 oil and use a mild EP multi-grade formulation with GL4/GL5 level performance.
1.The original Ford 9N and 8N owner's manual recommendation was Mild EP SAE 90 at temperatures above freezing and Mild EP SAE 80 at temperature below freezing.
2.When the temperatures drop there is a very noticeable differences between SAE 80 and SAE 90.
3.GL-1 oils contain zero EP additives and are not mild EP gear oils. In today?s classifications a mild EP gear oil would be GL-4
4.Ford M2C-134D is Ford's specification for what is now generically known as Universal Tractor Transmission Fluid.
5.It is not a GL-1 oil - it is a GL-4 oil
6.Per the OEM it has a kinematic viscosity of 60 cSt @ 40C and 9.4 cSt @ 100C
7.Per the OEM it has a viscosity index of 136
8.If you were to assign a gear oil viscosity grade to it, would probably be something like SAE 75W80
9.It is nothing like the common ordinary SAE 90 GL-1 gear oil which is in that jug labeled "specially formulated for old Ford tractors' that TSC sells.
To summarize - if you are in TSC and want a generic equivalent for Ford M2C-134D get the bucket labeled Traveller Premium Universal Tractor Transmission Fluid and leave that other crap for the people who stopped in for oil while on their way to buy a bridge.
TOH