I sure am glad I have pre emissions tractors. When I read about the woes you all have on here, I thank myself I kept my somewhat vintage units. I had started to contemplate about upgrading to new tractors last year but didn't and I'm quietly thankfull I never did. Sometimes procrastination isn't all bad.
Bad enough owning emissions compliant cars that I cannot work on except for oil and oil fiter changes.
At least the automakers seem to have a handle on reliable emissions componets. tractor manufacturers don't in my view. To make it even worse, no tractor manufacturer's diagnostic tools (code readers and such) can be plugged into a different manufacturers tractors. For example, the Kubota scan tool cannot access triuble codes or components failures on say a Mahindra tractor, heck, you cannot even plug into the Mahindra diagnostic port because every manfacturer uses a unique gateway that no others can physically plug into. No standardization what so ever, quite unlike the OBD port on cars and trucks where you can access most everything emissions and drivetrain related with just about any scan tool.... and it also appears that the quality and longevity of emissions related components on newer tractors is lacking as well. My Autel scan tool plugs into our GM as well as our Ford and reads the computers seamlessly. I cannot even plug the Autel into a late model Kubota because the diagnostic port is unique to Kubota only.
I think it's all pure unadulterated hog wash and why I'm glad I kept my 2 pre 4 tractors. No emissions related garbage to fail and no unique code reader to read trouble codes which a dealer will charge you for.
When tractor builders first got into the 4-5 emissions standards they should have all sat down and standardized their diagnostic ports and programmed their ECU's so they could be read with any scan tool, just like cars and light trucks of today can be read.
They are all basically using similar emissions hardware anyway but none of their ECU's are compatible with each other.