After a ton of research and recommendations from many of the fine folks on this site, I ended up going with the B&M 70264. The deciding factor really came down to how HOT it gets in my area. Also since my runner is pretty much reserved for nights and weekends, I've been doing a lot of in-town stop and go driving lately. And over-cooling wasn't a concern bc 1) it doesn't get that cold here, and 2) the B&M's bypass feature. I also didn't want to make the mistake of it not cooling enough for my needs. Several people I PM'd with mentioned still having high temps when in stop and go traffic or offroad, and some said if they could do it again, they would go w/ the 70264 rather than 70268 for their particular needs.
HOWEVER, I currently have no way to monitor my tranny temps, so I had to take the word and recommendations of others. So YMMV.

I think I topped out around 190 on the SR5. I took a pic of my Scangauge readout but must have deleted it.

On the SR5, I'm running in series because it's a new radiator. On the Limited, I did a bypass because it's the original rad.

I think, when the time is appropriate for the need, I'll add an electric fan to the front of my cooler with a manual switch. I do not want to rely on an automatic switch. I'm going to be moving to central Montana soon enough and my runner has the 2.7 liter. So, towing won't be too much of a concern with me. I might go so far as to add a second cooler (70264), but it might not be necessary.

I have a '97 4runner with the original radiator. Should I get a new radiator (if so which one?) or should I get a tranny cooler? I don't tow. I'd like to prevent the strawberry milkshake.

Get both.. Koyo rad and some kind of external cooler.

That sounds like the best option. Which part number for the Koyo rad and Koyo tranny cooler? Thanks!

I started mine on this link: B&M 70268 SuperCooler Transmission Cooler Install on a 3rd Gen

perma link #39. I did my own work, but I followed other members queues. I might have added a few things that were different, but not much.

Ok, thanks for the info. Is this the radiator you guys bought? http://item.mobileweb.ebay.com/viewi...d=150826612286

This is what you want , TYC is a KOYO
Its sold by amazon + ships free
TYC 1998 Toyota 4Runner 1-Row Plastic Aluminum Replacement Radiator : Amazon.com : Automotive

Thanks for the link however I have a question. It looks like that radiator is plastic aluminum, I heard that plastic radiators are not as good, is the majority of this radiator aluminum or plastic? I heard the plastic ones are easier to break on the trails.

The stock radiator has plastic tanks. (top and bottom) The core is aluminum.

Does anyone know how to tell if a 3rd gen radiator is original?

I flushed the transmission twice and now my first gear will work when it is cool but then stops working after the transmission warms up. Any thoughts on what could be the problem?