First of all, hi everyone! I found this forum while researching the bypass.

I bought a used 06 SE 4x2 w/ 94k miles for $6500 last week. Maintnace records from dealer in the glovebox sold me on it.
Car is in great shape and all lids have no sign of milky color.

I was paranoid so I had a buddy of mines do the bypass (back probs) my question is will the Puerto Rico weather overheat my tranny? We avrg 90 F and I do zero towing.

You shouldn't have an issue, but if you are concerned, you could always just install an aftermarket radiator. Unlike the genuine Nissan radiator, they aren't that expensive. Mine cost me $94 (not including coolant and new foam seals).

Thanks for the response, Its my first car, I needed something big so I could my back would be at ease while driving. I think I got a good deal since its had everything done to it and its last tune up was in january 2014.
The following were replaced:
-6 plugs
-Rack & Pinion
-Oil change

My mechanic says he sees some sillicon so hes guessing the chain tensioner was also done to it.

I'm in a tight situation right now so I did the bypass until the stock calsonic radiator fails. Thats why I'm doing the bypass for now

smj999smj wrote:You shouldn't have an issue, but if you are concerned, you could always just install an aftermarket radiator. Unlike the genuine Nissan radiator, they aren't that expensive. Mine cost me $94 (not including coolant and new foam seals).

Quick update, I just checked the ATF dipstick(pulled out 10mm bolt) and found that the ATF is neither red or milky. Its a light brown color similar to freash synthetic oil. level seemed fine and it was a clear light brown. I'm thinking the previous owner flushed the fluid with something else? Or is it breaking down?

Symbol wrote:
Quick update, I just checked the ATF dipstick(pulled out 10mm bolt) and found that the ATF is neither red or milky. Its a light brown color similar to freash synthetic oil. level seemed fine and it was a clear light brown. I'm thinking the previous owner flushed the fluid with something else? Or is it breaking down?

Fluid sounds spent, the fluid should be changed as it probably hasn't been changed before.

The first time I did a drain and fill on an R51, I drained the ATF into an old washer solvent jug and was concerned because the fluid looked dark brown. The same was true when I drained my own Pathy. I think it's just the way the fluid looks as I haven't had any issues with either trans and each has well over 30,000 miles since then. Nissan Matic "J" and "S" seem to be a darker red (IMO) than Dexron III/Mercon (which you should never use in an R51 trans). If it's shifting fine and no signs of water contamination, I wouldn't be concerned, but it wouldn't hurt to do a trans service. Most synthetic ATF's will work fine in the Nissan 5-spd. automatic trans, but make sure it says that it is recommended for use in Nissan Matic "J" or "S" applications. Castrol multi-import ATF and Valvoline Maxlife ATF, which I use, are two, good aftermarket alternatives to the expensive genuine Nissan ATF.

I guess if you don't do towing the small bypass "radiator" should be sufficient.