99A8Q

In fact, I was eyeballing the situation today (during an oil change). I have put trans coolers on several cars, and the A8 looks pretty straightforward. I would not be an advocate of bypassing the cooler core in the rad, though, thus putting the whole thermal load on the outboard cooler. That core is an extremely rare fail. Rather, I'd plumb the cooler on the downstream (post rad, "cooled" return) side. I think the "stacked plate" or B&M style cooler is superior, certainly more rugged than a tube and fin type. It's what you'll see on most race cars. You might also plumb in an external trans filter that uses a spin on chevy style filter. Waaay superior filtration to stock. All of this is available from Summit very inexpensively. IMHO, the fan is overkill-- though not if you're taking the rad out of the loop. For the truly paranoid, go crazy and add a cyberdyne digital trans temp guage (read the input of the rad, the hottest point. You're still under $300 in parts, even with braided hose. Just make sure and fill the trans (at the specified temp) with all the new plumbing in place. As a bonus, with a 18000 GVW cooler and 1 qt. filter you've also increased fluid capacity by approx. 2 liters.