Transmission Cooler Bypass
 

So I started to work out a plan to create a transmission cooler bypass. It started with a valve that I would open or close, and then I thought about doing it electronically with a temp sensor. Suddenly it dawned on me...that's what a thermostat does. So I need to know where I can find a three-way thermostatic valve. I found some on Ebay, but I was hoping to find a place that would carry them locally so I can look at a few. I hate to start ordering stuff and it not be right.

Also, what is the optimum temp range for the AW4? I need to decide when I want it to start opening and be fully open.

I know it's a overkill and somewhat pointless, but I think it would be frickin' cool to have a self regulating transmission cooling system!

The idea is cool..dont get me wrong, inovative..but i have yet to see a transmission fail due to low fluid temp..oil braks down with higher temps. Like the thinking out of the box...but you run the risk of adding a failure point(i.e valve stinking closed) that would be catostrpic if not caught

constant temp monitoring=gauges and what not, May prove to be more of a distraction than its worth.

But if your set on it..maybe use a solinoid valve to contol flow, check valve the oppisite side(return) to prevent back flow..

160-185 seems to be about normal op temp(recomended by hayden)My 09 silverado seems to run at 190

http://i1089.photobucket.com/albums/...FluidChart.jpg

Hopes this helps you...and dont let a A**hat like me from trying something different.:thumbup1:

I figured the low temperatures probably wouldn't hurt, but it gets so damn cold here in Fargo. Would the low temp cause the converter to take longer to lockup for overdrive? I figured if the valve failed then it would be as if there was no external cooler. This is kind of what I had mind. And I really do appreciate the feedback!!!

http://i50.photobucket.com/albums/f3...sjd/cooler.jpg

I am pretty sure my trans cooler has an internal bypass built in? I have one of the stacked plate ones rather than the tube/fin cooler

tonight when I get home I will look it up just to make sure

i believe? the gm hydromatic series transmssions would have a overdrive shift issue untill they reached around 70 degreees? i dont know if the jeeps have the same prob.


i cant remeber the exact spec... but mind you..in the stock config..with the cooler running into the radiator..at cold temps the radiator can accually act as a preheater for the trans.

Most of your good stacked plate coolers come with a bypass that if it fails will fail in the open position. Unless your doing some heavy towing or extended idling you really dont need the bypass, if I were you I would just run a cooler inline with the radiator it will keep the trans cool enough for daily driving in stop and go traffic and for offroading

Thermal bypass valve
 

There is a valve already built for that purpose. It's 'H' shaped and runs fluid thru it and back to the tranny (you don;t want to stop the flow) until it reaches setpoint (180 deg?) then opens to allow flow to the cooler. The stock radiator does provide preheat in cold weather. A gauge can be plumbed in-line to monitor temps. Just have to be aware of which line is the outgoing and which is the return line. I have that mod scoped out for mine so I can tow my CJ.:nuke: