Oil and Transmission Coolers for 1993 Dodge with 250 Cummins Diesel Operated in Desert Climate

Updated 09/04/2013 | Published 08/30/2013

Question:

I have a 1993 dodge w250 with the cummins diesel, I do a lot of heavy pulling and to top it off I live in the desert where it can reach 125 degrees in the summer. Air conditioning is absolutely essential here, the problem is that dodge reccomends not using the A/C when pulling heavy loads due to possible overheating. And if you run the a/c while pulling in this heat it does overheat. What Im looking to do is relocate the cooling devices so that they are not all concentrated in the front of the truck. I want to by-pass the factory trans cooler and install one or if needed two coolers with fans below the truck, as well as ad an additional engine oil cooler. Do you think this would be permissable and which coolers would you reccomend that would be large enough to handle the heat? You help is much appreciated.

asked by: Ron W

Helpful Expert Reply:

Since oil and transmission coolers come in a range of sizes and types, and can mount in any location that will provide air flow (or in the case of fan-powered units enough space for convenient mounting) you can install both a secondary transmission cooler and a fan-powered oil cooler.

I recommend using a secondary transmission cooler in addition to the OEM unit rather than bypassing it. The secondary cooler will take the already-cooled transmission fluid from the radiator and further reduce its temperature before returning it to the transmission case. A fan-powered oil cooler in addition to the secondary transmission cooler will allow you to reduce the Cummins oil temperature even when not in motion and this will be a good choice given your desert location and need to use the AC system.

The space in front of your AC condenser remains the best choice for positioning the secondary transmission cooler but frame-rail types are available if you prefer, such as the Derale # D13265.
Frame-rail types are less efficient but avoid the need to mount in front of the condenser. The fan-powered oil cooler will not be sensitive to placement since it does not rely exclusively on passive air flow for cooling and can be positioned almost anywhere that is convenient.

Coolers are neither vehicle-specific nor fluid-specific; you can use any cooler that will fit the space you have to mount it and use for either transmission fluid or engine oil. I have included a link to our page for transmission coolers for your 1993 Dodge. You might also refer to the two linked articles that cover much about the types of coolers available.

A second link will show you our Class V fan-powered coolers. While these may be labelled as transmission coolers they are suitable for use to cool engine oil as well. These are typically 4 to 6 inches deep (due to the fan) but will provide the maximum cooling efficiency for your oil.

expert reply by: Adam R