Ackattack1

iTrader: (7)

I'm building a '68 C-10 that is running a stock 5.3L and stock 4L60E for now. I'm getting ready to do the radiator and tranny cooler.

Eventually I'll have a LS1, build up the tranny, and get a converter in the 3200-3600 range. It has 4.10s, will weigh ~4000 pounds, and I'm wanting to put down 400 RWHP, if any of that matters for tranny coolers

The stock style radiator has a build in tranny cooler. I figure this would be fine for now, but since I'm building it now, I'm going to go ahead an get an external tranny cooler.

So should I even use the radiator tranny cooler, or completely bypass it. Also, what size of external tranny cooler should I use?

bmxer8699

iTrader: (16)

yes, use both. That is what im doing and my tranny temperature is at 186F at 95F in traffic.

Sinister95Z

iTrader: (30)

I know a couple of the board sponsors recommend bypassing the stock radiator cooler. Running the tranny fluid through a hot radiator kind of defeats the purpose...

pcmcobra

iTrader: (4)

I am bypassing mine...
just cause I don't want the ugly rubber hoses and can't find fittings that fit/ look worth a you know what.
I cut the stock 4l80 lines behind starter, used compression fittings, then -6 to cooler up front.

Urban Legend

iTrader: (5)

By pass the radiator. Thats for sure.

koolaid_kid

iTrader: (21)

Another vote for the bypass. The radiator can actually add heat if you have an aftermarket installed. Mine ran ~165 yesterday in 90 degree traffic.

big wally 55

The cooler installation recomendation should be by location . If you are in an area where it gets drastically cold you need the transmission fluid to get up to temurature during the winter ! Here in Texas we usually bypass the radiator . If you do that I would recomend getting a self regulating cooler .
As for cooler size , on a truck you have a lot more room for a cooler than on an "F" body so I recomend going with the largest cooler that will fit . Overkill is good in this department !! Try to get one with an installation kit with the metal brackets used for mounting as opposed to the "zip-ties" through the radiator . Have fun .

John

will82

Whatever you do, don't use the garbage lines that come with the cooler if you buy a B&M,

Buy some ss braided hose or even use hard lines. Using the rubber lines B&M provided got me well acquainted with the color and smell of transmission fluid.

01ssreda4

iTrader: (96)

if you put a big anough aux cooler in then yeah bypass the radiator. mine runs through both.