You might try the aftermarket performance brake suppliers that supply to the hot rod and restoration community. My van stops pretty darn well. I have not had any performance issues such as lack of stopping ability or fade. The only real reason I would go rear disk brakes is for looks. I like the look and peddle feel of 4 wheel disk brakes behind the see through alloy wheels. They just look better. What is going on which makes you want to upgrade the brakes? Even the European vans get rear drum brakes. The front ones are already big 12 inchers. They are the biggest brakes sold on them world wide. This is not a 3/4 ton truck. It's a 1/2 ton light duty truck. If your going to haul 2 tons around, or tow a bigger trailer, you need a bigger more heavy duty build truck. It has modest performance capabilities designed in. We get the hot rod engine and transmission for this van already. It's already been beefed up a little bit for North American use and abuse. I suspect that the diesel versions many are hoping for would prove very spendy and lacking in the get up and scram department. A big chunk of diesels are sold with 5 or 6 speed manuals. We would probably call them under powered and or too slow for our driving conditions. And the take rate for the manuals would probably be less than 4% of sales. Right now I cannot think of a new van sold here that does not come standard with an automatic. Their vans can be ordered with a 5 speed automatic. We are the only ones that get the 9 speed automatic. But we do start with the biggest brakes even on the base models. They do not. Also the rear brakes are of a heavy duty design configuration that is supposed to provide for extended wear life.