How to: factory auxiliary trans cooler upgrade

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randomguy

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I would personally run the radiator cooler and then add an auxiliary cooler into the circuit. It’ll not only help keep the trans cooler when hot but it will also help it get to operating temperature faster. Even though the radiator is 195 degrees the coolant is still very effective even in hot climates. Liquid cools better than air. OEM’s still use this setup because it’s effective.

I owned a 93 Exploder that I gave to my mom several years ago. The A4LD is notorious for early failure. Original trans now has 180k on it with nothing but two driveway flushes since I bought it with 125k on it. I’d opine the secret is the auxiliary cooler the original owner installed. The fluid goes through the radiator first and then the cooler. Shifts like new.
 
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Just completed this upgrade on my 1998 Silverado Ext Cab. It was born without the optional factory transmission cooler. Went to the junk yard to purchase the brackets and used rubber hose for the inlet and outlet of the cooler. Great write up! Tomorrow I start the electrical for the electric trailer brakes!
 

blackdeathmessenger

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I would personally run the radiator cooler and then add an auxiliary cooler into the circuit. It’ll not only help keep the trans cooler when hot but it will also help it get to operating temperature faster. Even though the radiator is 195 degrees the coolant is still very effective even in hot climates. Liquid cools better than air. OEM’s still use this setup because it’s effective.

I owned a 93 Exploder that I gave to my mom several years ago. The A4LD is notorious for early failure. Original trans now has 180k on it with nothing but two driveway flushes since I bought it with 125k on it. I’d opine the secret is the auxiliary cooler the original owner installed. The fluid goes through the radiator first and then the cooler. Shifts like new.

I actually did this with my 700r4 since I blew up the transmission that was in the truck after I rebuilt the engine and added some power. I was also strongly urged by my transmission rebuilder to use Dexron 6 after he fixed it. 12,000 miles later, still working great
 

GMCTRUCKS

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Which line on my radiator is the high pressure Trans line GMC F/S 1993 1/2 ton Ext/Cab??

I want to use a B&M Trans cooler I have.

Another question is which Trans which line do I put on the lower Trans cooler high or low pressure line???

I’m just going to tap into my Trans lines with a rubber hoses able to run Trans fluid and use the correct clamps or double them as well.
 

Schurkey

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Which line on my radiator is the high pressure Trans line GMC F/S 1993 1/2 ton Ext/Cab??
Lower tube on the radiator should be the cooler supply.

Upper tube on the radiator should be the return back to the trans.

Another question is which Trans which line do I put on the lower Trans cooler high or low pressure line???
Around here, it's probably better to have the hottest fluid go through the aftermarket cooler, then go through the radiator cooler, then back to the trans.

In a warmer climate, I might do things differently. Or maybe not. There's at least three ways to plumb the second cooler--ahead of the radiator cooler, after the radiator cooler, or in parallel with the radiator cooler. They all have advantages and disadvantages.

I’m just going to tap into my Trans lines with a rubber hoses able to run Trans fluid and use the correct clamps or double them as well.
You're looking for power-steering return hose. I get mine at NAPA; but any decent parts store will have it.

Ideally, you'd use clamps that DON'T emboss a million diagonal ridges into the hose, like in the fuel system photo below. Those clamps will be harder to find since the PS return hose has a pretty hefty wall thickness.
Photo 1. ****** clamps vs. "Fuel Injection" clamps on a fuel system.
http://hbassociates.us/Fuel_Pump_9.jpg
You must be registered for see images attach
 

GMCTRUCKS

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Lower tube on the radiator should be the cooler supply.

Upper tube on the radiator should be the return back to the trans.

Thanks Thanks buddy

Around here, it's probably better to have the hottest fluid go through the aftermarket cooler, then go through the radiator cooler, then back to the trans.

In a warmer climate, I might do things differently. Or maybe not. There's at least three ways to plumb the second cooler--ahead of the radiator cooler, after the radiator cooler, or in parallel with the radiator cooler. They all have advantages and disadvantages.


You're looking for power-steering return hose. I get mine at NAPA; but any decent parts store will have it.

Ideally, you'd use clamps that DON'T emboss a million diagonal ridges into the hose, like in the fuel system photo below. Those clamps will be harder to find since the PS return hose has a pretty hefty wall thickness.
Photo 1. ****** clamps vs. "Fuel Injection" clamps on a fuel system.
http://hbassociates.us/Fuel_Pump_9.jpg
You must be registered for see images attach
 

97K1500Silverado

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B&M 70266 is $130 Feb 2021. Didn't someone do a 1500 4l60 trans cooler upgrade using the cooler from a 2500 with a 4l80?
 

SAATR

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B&M 70266 is $130 Feb 2021. Didn't someone do a 1500 4l60 trans cooler upgrade using the cooler from a 2500 with a 4l80?

The 70266 and 70272 weren't the cheapest options for their cooling capacity when I did this 9 years ago, and time hasn't made them any cheaper. The deciding factor on those specific coolers were that they had a similar form factor to the original cooler. If mounting in the factory location isn't a concern, then get whatever fits your budget.
 

df2x4

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