Engine/Transmission (1994 - 1998) transmission cooler replacement

[Jim Fulmer]

Any of you ever get rid of the stock transmission cooler and the liquid one and go to just a bigger cooler in the front? Looking at having to get rid of the liquid cooler.



Jim

 

[Midnite]

I'm not sure what kind of winters you have in Oklahoma, but in cold temps the liquid cooler helps bring the transmission fluid up to operating temp much quicker. I'm not sure how much of an issue it would be to eliminate it and go with a bigger oil-to-air cooler. Most likely the transmission would just refuse to go into OD for a longer period of time until the fluid eventually heated up.



Anothing thing to keep in mind is that liquid cooling is much more efficient than air cooling, so you may need a significantly larger oil-to-air cooler. Of course this is balanced by the fact that coolant temperature is much hotter than ambient air temperature.



This really isn't any help, practically speaking, but since nobody'd replied yet I figure I'd through out a couple of things that might be worth some thought.



Mike

 

[Jim Fulmer]

Oklahoma winters aren't that bad for temps but I hear what you are saying, I thought I would ask before I call DTT about it!



Jim

 

[fortunate1]

Air-to-Air ATF coolers

Jim, I've added an 18-pass cooler (12" x 18") and fan under the driver's seat, and I re-routed the ATF away from the radiator coolant cooler into a small air-to-air cooler. Next time I change the engine coolant, I'm going to snatch out that miniature heat exchanger and straight-line the radiator fluid line too.



Heat transfer is much more efficient with liquids than with ambient air, so I'd rather not subject the ATF to 185* F coolant. That's not going to cool it, but heat it up. At least that's the plan. If 185* F "COOLS" the ATF (at least long-term), then I've got problems.



My temp guage (sensor in the pan, so I watch for trends and overall averages) shows the ATF at 50*F to 55*F over the ambient air temp. The temp always stays below 150* F unless I'm in some heavy stop-and-go traffic. If it goes to 150* F, I turn on the fan to keep it from exceeding that temp. So far, so good. I've driven in a lot of situations this summer that raise ATF temps, and the air cooling system has worked very well. Even on the highway at 75 mph and 102*, the guage stayed just below 150*F. The fan bails me out when air movement isn't enough.



Good point about cold weather, though. The stock setup does help warm the ATF in the winter; so does driving. But my weather is about what Tulsa gets, only 2 days later. And the ocean & bay keep things a little warmer than inland residents see.

 

[Jim Fulmer]

Good point, kinda sounds like what the drag racers do putting the transmission cooler at the back of the car with a fan on it.



Jim

 

[jburnes]

Jim, I put on an aftermarket cooler w/fan and temp sensor and love it. It kick's on at 180 degrees and does great. I cut a flared my return line just before the last 90 and ran to an aux cooler. Use the best 1/2" line possible (300 temp rating) and have at it. I have more info under "temps all over the place" and my reply to that. Let me know if I can help Ya?

JB





2500 slt auto, 4X4, 3:54, Banks Bombed, 4" T-T, 285's, Amsoil B-B

transmission done right...

 

[P Madrid]

I'm also looking into getting rid of the liquid cooler. There are this coolers I been checking out, stack coolers. They are sold by different performance shops but the two most common manufactures are Hayden and Tru-cool. Some set ups come with a fan and a fix or adjustable thermostat to turn on the Fan. I plan to run an ATS transmission and will ask Clint what he thinks of this coolers.



Pablo

 

[inarush76]

coolers

There are a number of cooler/fan setups on the market. Dodge offered one at one time that mounted under the bed. You may need to look at engine oil cooler/fan set ups to be able to get the 1/2" flare fittings to match the cooler lines. Most "trans" coolers are 3/8" max. No hotter than the DTT converters/trans run, controlling temps shouldn't be too difficult.

James

 

[LaserBob]

Cool Fuel

Jim,



I ran big rigs for over 20 years before I got my CTD. I did the cool fuel thing about '88 or '89 to try to improve mileage in a series 60 Detroit. I could record about a . 5mpg improvement over the long run by cooling the return fuel. I put coolers on every one of my trucks after that. I thought about doing it to my pickup, but never have done it.



I used an air/oil transmission cooler that I simply mounted in some location where there is an air stream flow and few rocks to hit it. Just take your return fuel, at the hottest point you can get to it, and route it through the cooler before it gets sent to the tank. The hotter it is when it enters the cooler, the more temp drop you can achieve. I would also put a valve in the system to bypass the cooler so that in very cold weather I could retain some heat.



I liked the way it worked. No moving parts, but the fuel.



Give it a try.



Good Luck, LaserBob