Steve,

No, I havn't checked the maxims parts. I will have a look.

I know that for billions parts which is my case for this product, I could obtain a specific product or specification. I've to try, but I'm afraid to use a uC which has not been massively used before me in automotive applications in this temperatures range.
I won't have feedback from the market concerning reliability. We've specified 5 ppm at 0 kilometers !
Moreover, our curstomer will be sensitive to the microcontroller's choice. It's impossible to speak about some manufacturers because they have not the "automotive feeling"... Yes, ... customers are like this when buying billions products.

Stephane