Will The Derale Transmission Cooler Fit and Cool 2006 Chevrolet Silverado 2500HD With Allison Trans

Expert Reply:

Ideally you want to keep the temperature of the transmission fluid below 200 degrees. You cannot cool transmission fluid too much. The Derale Transmission Cooler, part # D13504 is not a cooler recommended to work with your existing cooler on your 2006 Chevrolet Silverado 2500HD with Allison Transmission.

I spoke with my representative at Derale, and informed him your truck is equipped with an Allison Transmission. He recommended the Derale 19-Row High-Performance Stacked-Plate Cooler, part # D51908 for your vehicle. You will also need Derale -8 AN Female Swivel x 1/2" Barb Hose Fitting, part # D98202 and order a quantity of 2.

You will need to install using extra hose and barb connectors. I believe the existing transmission cooler on your 2006 Silverado 2500 HD, uses 1/2 Inch Diameter transmission lines. If that is the case, you will need additional fittings to install part # D51908 in-line with your existing transmission cooler. You will need Derale 1/2 Inch Male Barb Fitting, part # D15712 which comes with 2 fittings. You will also need a quantity of 2 for the Derale 1/2 Inch Female Barb Fittings, part # D98106. For extra hose, you will need Derale High-Temperature Replacement Hose, part D15701 which is 5 feet in length, or part # D15700 which is 10 feet in length. I would recommend part # D15700 just to make sure you have enough hose.

To install the Derale Transmission Cooler part # D51908 with extra line and connector, first you will need to cut the return line from your existing transmission cooler. Then, attach Derale 1/2 Inch Female Barb Fitting, part # D98106 and attach Derale 1/2 Inch Male Barb Fitting, part # D15712 using Loctite Thread Sealant 545 part # LT37482. Then, connect one end to the existing hose, attach a hose to the other end of the combined fitting and connect to Derale Cooler, part # D51908. At the other end of the cooler, determine the length of hose needed, connect one end to the cooler, make the same fitting with part # D15712 and part # D98106 using the Loctite Thread Sealant, part LT37482. Attach one end of the combined fitting to the hose coming from the Derale Cooler, and the other end to the hose that is the return line going into the transmission.

For all the connection points you make with the hose, you will need Derale Stainless Steel Hose Clamps, part # D13008 which comes with 4 clamps. You will need a total of 6 clamps, so you will need to order a quantity of 2 for part # D13008.

The ideal spot to mount part # D51908 for maximum efficiency is behind the front grill but in front of the radiator of your 2006 Chevrolet Silverado 2500 HD with Allison Transmission. You will need to measure, as part # D51908 is 13 inches wide, 7-7/16 inches tall and 2 inches thick.

When installing a cooler in front of the radiator it will not dramatically impact the water temperature as the cooler is a flow through device. Air will still flow through the transmission cooler and reach the radiator, the air may be slightly warmer but would not be significant enough to raise water temperature. The radiator will still have surface area that is being hit directly with flowing air and air from the cooling fans.

I have linked an FAQ on transmission coolers that may be of good reference.

expert reply by: Reno H