If you do decide that your ZF needs attention, do NOT bring it to anyone in Saudi. Nothing personal, but it is a fairly specialized box that requires either someone with a WHOLE lot of patience and talent, or you will never get it back together in one piece.
In the end, it is just a transmission, but it is not a common one (a mechanic will not have seen one before) and it has a lot of little tricks that could bite you. I would be deathly afraid that someone would start to take it apart, realize they are in way over their heads, and you are screwed. If it were my money, which I don't spend unless I think I have to, I'd send it via boat to the US to have checked out if I thought it was suspect.
It won't be cheap, but every article and every webpage you read about the Pantera repeats that the ZF is very stout, but very expensive. I don't think there are many shortcuts...
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