Comparing Derale Transmission Coolers for 2009 GMC Sierra SLT 1500 5.3L Towing 26ft 5,400lbs Trailer  

Question:

Expert Reply:

Good news, I can help you compare the two Derale transmission coolers as well as help you select the right one for your 2009 GMC.

The main differences of the two transmission coolers # D13503 and # D13504 are the size and Class number. The # D13503 measures 11 inches wide and 8-3/4 inches tall while the # D13504 measures 11 inches wide and 12 inches tall. The # D13503 has a Class III rating and the # D13504 has a Class IV rating. The Class rating to let customers know that if they have a Class II hitch on their vehicle, then a Class II cooler should be sufficient, but they can always use a larger cooler for more cooling if they like. Both coolers will require the # D13035 transmission adapter fitting for your Sierra though.

The general rule is that transmission fluid cannot be cooled too much, so using the largest cooler that will fit is a good idea, especially if you are towing. The only reason not to add the largest cooler possible would be if you live in a very cold climate where temperatures are commonly below 0 degrees and you have a transmission cooler installed. This would warrant warming the engine for a few minutes. Most people warm the engine in these cold conditions anyway, so size is not typically a factor.

I would recommend if you have the room to go with the larger # D13504 cooler, because as stated above you cannot over cool your engine.

I have linked the above mentioned products to this page as well as a few help articles about the best places to mount the cooler for your convenience.

expert reply by: Jackie C

0