Derale Transmission Oil Cooler with Bypass (1 Viewer)

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jaymar

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Anyone done this or something similar? Any reason NOT to do it? Where would you mount it? Thermostat-controlled bypass opens up and runs fluid through Derale cooler when fluid temp hits 180. Where and in what position would you mount thermostat? Found a few references in various threads, but nothing with any real detail. Thanks!
 
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Are you using this in place of the factory system or to supplement it? Personally I'd only use it to supplement and would place the thermostat down stream of the outlet on the factory cooler so it opens if the factory set up is not getting the fluid cool enough. Either that or I would consider not using the thermostat at all and just have the fluid always go through both.
 
@voodu3 you mentioned using a Derale 13403 1000 Series with no problems. Any tips/photos on installation?
 
Are you using this in place of the factory system or to supplement it? Personally I'd only use it to supplement and would place the thermostat down stream of the outlet on the factory cooler so it opens if the factory set up is not getting the fluid cool enough. Either that or I would consider not using the thermostat at all and just have the fluid always go through both.
Supplement. Currently in SoCal, hit 120 here last year. Want the bypass for trips north, where using both may not get the oil up to temp...
 
Sounds complicated and adds failure points, Just run a bigger cooler.
 
Sounds complicated and adds failure points, Just run a bigger cooler.
But the oem is so ingenious, with the rad acting as both heater and cooler for tranny fluid. :)
 
Related question: What is the ideal tranny-temp range for the 95-97 with the 343? The Derale thermostat-bypass opens up at 180 F--meaning the fluid temp is likely to remain below that.

Also--closest imperial hose size--3/8?
 
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But the oem is so ingenious, with the rad acting as both heater and cooler for tranny fluid. :)
Did you truck over heat in the hot temps last year. For the couple days it gets that hot I think you over thinking it. If everything in the cooling is working correctly the truck should be able to handle those kind of temps. JMHO
I'm thinking in places like the middle east they see temps like that on a regular basis.
A few years ago I did a job in White Sands New Mexico, daily temperatures were 125 -127 degrees We were running everything from small generators to large cranes in those temps with out issue and rest assured the AC was running full blast on anything that had it.
Generally transmission temps follow engine temps if everything is working correctly, so if the engine is not over heating the trans should be fine,again JMHO 🤷‍♂️ ;)
 
Tranny fluid line for aftermarket cooler (Derale 13403)--3/8 or 1/2 inch are only choices for thermostat in/out. Do I go with 3/8? Thanks for any help!
 
to put this the other way, is there any issue running a tranny with cold fluid?

if you're in a cold environment on occasional trips only, I'd think run a
larger cooler, and leave the thermostat out of the system. Build primarily for YOUR typical conditions, not the occasional trip

I think larger tranny fluid coolers are reasonably commonly used in Australia by people who are towing heavy loads regularly in hot conditions.
 
I would just run an oversized cooler before the radiator heat exchanger, that way it’ll get cooled off but then warm back up to the proper temp from the engine coolant.

Doing a quick google search, that’s how the factory one is set up. So just replace the factory one with a bigger one if you’re concerned about it.
 
Okay. So if I'm running new lines--3/8 or 1/2? :)
 
Coming back to this (now that I can actually do it) and simplifying as suggested by several folks above...

Stock cooler measures 10w x 13h x 1-1/2 thick, excluding the mounting hardware. There's a decent amount of space in front and behind.

For the time being, I'll be using a radiator that has no pass-through provision for the tranny line, so fluid will go directly to cooler and return to tranny. I may switch back, and I may not. I don't see any better place to put a tranny cooler, so going bigger means blocking more air, unless it's just thicker. So...

Given we're now 30 years on, tech-wise--will a Derale or Earl's Perfomance or Mishimoto etc. fluid cooler of the same size outperform the OEM, or is it all the same? Any thoughts on longevity vs OEM? Thanks for your thoughts...
 
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Have had any issues with the trans overheating? I have never had issues with the trans and heat on my 96. If you are trying to cool in the summer heat I would look at the fan clutch, radiator, etc. The one mod that has had the most impact is hood vents, night and day especially with the supercharger. As someone else mentioned a pusher fan is great for low speed on trail or traffic.
 
Have had any issues with the trans overheating? I have never had issues with the trans and heat on my 96. If you are trying to cool in the summer heat I would look at the fan clutch, radiator, etc. The one mod that has had the most impact is hood vents, night and day especially with the supercharger. As someone else mentioned a pusher fan is great for low speed on trail or traffic.
Can't say I'm knowledgeable enough to evaluate the pros and cons of hood louvres at this point, but I did come across this, which gave me pause...

 

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