Question:
I have a 2008 GMC Sierra 4X4 1500 5.3 L auto with only 20,000 miles in very good shape. My truck gets over heated when I pull my new 4000 LB trailer up a grade. I would like to add a heavy duty trans cooler and any additional parts I would need. Also, should I add an auxillary electric fan?
asked by: Ron
Expert Reply:
If you are pulling a trailer under the towing capacities of your 2008 GMC Sierra 1500, the engine temperature of the truck should not overheat. I would recommend having the vehicle looked over by your GMC dealership.
What I would recommend is adding a combination transmission and oil cooler, as well as a cooling fan. This will cool the transmission fluid, the engine oil, and engine. For this, I would recommend the Derale Combination Transmission and Engine Oil Cooler, part # D15903. You will need to measure to make sure you have room to mount the cooler, as it measures 17 inches wide, 12-1/2 inches tall and is 3/4 inches thick. The most efficient place to mount a cooler is behind the front grille, in front of the radiator.
You could also add an electric fan setup. I would recommend the Derale Radiator Fan, part # D16816. You will also need to measure to see if you have space to mount his fan. Since this fan has a high and low setting, I would recommend using the Derale Dual-Fan Adjustable Fan-Control, part # D16789.
Another option would be to have an all in-one setup like the Derale Electra-Cool, part # D15220, which is an engine oil, transmission cooler, with an electric fan. In addition, you would need Derale Remote Engine Oil Cooler Installation Kit , part # D15752, and Derale Installation Kit, part # D13006.
I have linked an FAQ on transmission coolers and an FAQ on electric fans.
expert reply by: Reno H

Products Referenced in This Question
Derale Electra-Cool Combo Engine and Transmission Cooler Assembly w/ Fan, -8 AN Inlets - 4 Pass
Product Summary:
Transmission and Engine Cooler
With - 8 AN Inlets
Product Specs:
15-3/4W x 11-1/2T x 4D Inch
Standard Mount
Derale Remote Engine Oil Cooler Installation Kit w/Thermostat Fan Control
Product Summary:
Engine Oil Coolers
Accessories
Product Specs:
Installation Kit
Oil Cooler
Derale Combination Transmission and Engine Oil Cooler for GM Applications
Product Summary:
Transmission and Engine Cooler
With 11/32 Inch Hose Barb Inlets
Product Specs:
17W x 12-1/2T x 3/4D Inch
Standard Mount
Product Page this Question was Asked From
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