Ahh. Gotcha.

 

Transmission Cooling: You must have a transmission cooler in your radiator regardless of what someone has told you for the transmission to last. Auxiliary coolers are just that, in addition to. Water cools 32 times better (faster) than air always, period. The transmission fluid comes directly from the torque converter at a much higher temperature than the water in your radiator and is cooled to the water temperature fast. Then it goes to the auxiliary cooler to be cooled far below the water temperature. If you don't need a cooler in your radiator why does GM spend all that money doing so? If you wanted to cool a red hot piece of steel fast would you stick it in water or air, see the point. For the best cooling you need both water and air cooling for the transmission to be cooler than the motor.

 

GM????

My truck is prooves that theory incorrect

 

I found that info I posted on another forum. I no speakie GM personally. Have never, will never, and flat won't. If you cut me I bleed Ford Blue. The drops even come out Oval shaped.

 

That's funny stuff!

 

Seriously, I would say if you're not going to be doing any towing, and don't have a lockup or stall converter, a large plate cooler is sufficient.
JMO, of course.

 

Bobby, you I would never argue with. I have always heard radiator cooler 1st then an auxiliary. But you bring up two strong points. 1. history with your truck. 2. "PLATE" tranny cooler.
So OP, if your radiator's condition is questionable, I'd buy an A/T radiator. If it's in Good condition try a nice sized (large) PLATE tranny cooler. I don't think the radiator is going to be that much more money. But who knows?

 

You know, I bought this 63 Unibody for $50 when I was 21 years old. It already had the 390/C6 drivetrain. The truck originally came with an I6, manual trans and the previous owner never changed the radiator. When I got the truck, it had a huge round tube & fin trans cooler that was half the size of the radiator core. I drove it for years with the tube/fin cooler with no problems until the cooler sprung a leak. It was replaced with a plate cooler that my dad had lying around his shop. It's funny because, since I never had any trans problems, I never upgraded to an automatic trans radiator. I never even thought about it. The truck still has the same radiator that it had when I got it although it's been to the radiator shop for tank leaks in the past. My truck is proof positive that you do not need a radiator trans cooler for trans longevity but the truth of the matter is that a truck should really have both a radiator trans cooler and an auxiliary trans cooler.
I think once I get my short bed painted, I'll upgrade everything in the Unibody (stroker motor, trans, No Limit IFS and, of course radiator )

 

I had a friend that had is ford van like an Arrow Star mini vans tranny that went out with in 2 weeks after being fixed. Then while visiting is dad that lived in Palmdale Ca.hot desert type area over 100 when he was their that summer, this was about 150+miles from San Jose.

The shop in Palmdale found that the wrong Tq-convertor was put in by the first shop in SJ. My friend asked about adding a lager auxiliary cooler as he told them he was to be moving to Michigan in a month or so and would be pulling a trailer. So they put on a aux cooler.

The first shop made good & paid for the work Tq-convertor installed as in was warranty and was there screw up.

Okay so 2 yrs later the tranny goes out again. This time the guy at the shop in Michigan said that your tranny went bad because your fluid stayed to cold and did not burn off the moisture that accumulates inside with in the tranny.

In this cold parts of the country when using a auxiliary tranny cooler that big. Plus I guess it was also hooked up wrong, the fluid did not go through the Radiator at all just the auxiliary cooler was being used.

He was told by the shop guy that the Radiator needs to be inline as the oil exits from the radiator this warms up the oil, where as just using the Aux. cooler won't any good removing moisture in winter driving in the Northern states.

So to cool is no good & to warm is no good.

Orich.

 

That's what I thought too Orich. Makes more sense to me. Everything has a premium operating temp, usually 150-200*