Transmission Cooler for HDJ81 (1 Viewer)

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They're pullers, again terrible pics and was trying to show the size and NOT drop the cooler while taking the pictures. John from Castle Fab and I discussed building the bracket at the same 45ish degree angle as the slider bracket with the coolers inlet/outlet on top closest to the frame. I want it above the bottom of the frame, well protected. A Jay Leno's Garage where they featured a 60s mustang gave me some good ideas. I hope to share more pictures Friday.

Yes, the cooler running through the radiator was designed to get the trans fluid up the operating temperature more quickly. It doesn't do a good job cooling at all and is easily over taxed. Regarding the temp guage if you have access to a machine shop you can drill and tap the out going hot fitting yourself and use whatever temp guage you'd prefer. The union is actually not that much money if you want to save on down time.
 
Couple of pics, not plumbed or wired yet.

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The Derale installed using custom bracket next to the transfer case. The tcase skid plate mounts on the same bolts and protects it. Jason also installed a manual shut off switch on my dash for going in water. The fan turns on at 180F but my temps are typically lower so it seldom turns on.

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Finally catching up on this thread and project. That looks great! What AN size did you go with? Would your fab shop make a second bracket?

Thanks a lot!

We used the 8AN fittings. Best if you contact Jason directly at Cruisin Offroad.
 
We used the 8AN fittings. Best if you contact Jason directly at Cruisin Offroad.

I'm going to try to replicate your setup because you were able to use the larger 15960 (46,000BTU) cooler. Any lessons learned before I start buying? Did you buy direct from Derale? Thanks so much for your time!
 
I went with 6AN to keep the size as close to original as possible in the hopes to keep the pressures up.

edit from the desktop: it's been a long time since I've actually worked on an automatic transmission. However, I figured it's worth noting fluid pressure is important to auto transmissions operation. As with most "shift kits" you're increasing pressure to get more control and firmer shifts between gear changes. Hence my reasoning why to go with 6AN.
 
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I'm going to try to replicate your setup because you were able to use the larger 15960 (46,000BTU) cooler. Any lessons learned before I start buying? Did you buy direct from Derale? Thanks so much for your time!
It doesn’t matter where you buy. I’m averaging 180-190f around town which is good. For some reason my thermostat isn’t turning on the fan so I need to solve that.
 
I went with 6AN to keep the size as close to original as possible in the hopes to keep the pressures up.

This is my last decision point, 6 vs 8 AN, @J2P why did you guys go with 8AN?

Also what thermostat did you guys go with? The one from Wholesale Automatics is nice but the same price as the cooler...
 
This is my last decision point, 6 vs 8 AN, @J2P why did you guys go with 8AN?

Also what thermostat did you guys go with? The one from Wholesale Automatics is nice but the same price as the cooler...
So the 6AN kit I believe is a direct bolt on and the thermostat and fittings are all included in the 13960 kit. I went 15960 because it was all 8AN so little more volume in the lines. 8AN is 1/2” inside diameter versus 6AN which is 3/8”. The lines are also included in the kits.
We wired mine with a manual shutoff on the dash and it could be that it isn’t sending power to the thermostat. My problem and most likely nothing to do with the kit.
 
@J2P is correct regarding the 6AN kit being 13960. my setup runs the same thermostat. I too am running a manual over ride.

I ordered my parts through Amazon.

 
So the 6AN kit I believe is a direct bolt on and the thermostat and fittings are all included in the 13960 kit. I went 15960 because it was all 8AN so little more volume in the lines. 8AN is 1/2” inside diameter versus 6AN which is 3/8”. The lines are also included in the kits.
We wired mine with a manual shutoff on the dash and it could be that it isn’t sending power to the thermostat. My problem and most likely nothing to do with the kit.

I should have said temperature sensor. It's my impression that the thermostat starts the fan at 180 deg but won't give you a constant temperate readout to a gauge in the cab. Am I wrong or can you hook up a gauge to the fan on/off sensor?
 
I'm sure there's a away to do it. The autometers I went with have a trigger wire which you can use run relays to have that ability. I'm using them to operate warning lights.
 
Can't figure out how to edit from my phone... regarding a temp gauge sending unit. I purchased an extra hot side union which is what Wholesale Automatics does then drilled & tapped it to save the down time. From memory the part was less then $20, however it's been a few years since it was purchased.
 
Finally getting back to this....did any of you gents get your units plumbed and can you post pictures?

Thanks!
 
Plumbing this week, along with the new intercooler & airbox from pdi.
 

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