DT 12 Transmission Fluid

I'm pulling my hair out here... just finished rebuilding my 2016 DT12 and cannot find the recommended oil for it anywhere I'm not sure why but everyone seems to be back ordered... Truck is now sitting and I'm getting desperate. Does anyone know if I can use Full synthetic 75W 80 which is what Volvo recommends for their iDrive?
Thanks

 

$553.. for a 5 gallon bucket!

Thanks for the replies and info, this whole DT12 has been a nightmare, starting from tying to figure out the diagnosis for the issue... but we got it going finally.

 

Well my mechanic tested everything that Detroit recommended as far as the trans dropping into N when I would come to a stop, we pulled it out stripped it down thought maybe it was the split pin bushing, but turned out to be a hairline crack where the air line from the cpu enters looked like at one stage, maybe even from the factory it had been cross threaded and that all it took for a quick drop in Air to send it into N..

 

This air fitting was cross threaded and had a hair line crack through the housing. Hope this helps, meant to say TCM in previous post not CPU.