Derale Combination Transmission and Engine Oil Cooler for GM Applications

Part Number: D15903

$244.37

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derale transmission coolers standard mount combination and engine oil cooler for gm applications

derale transmission coolers standard mount

derale transmission coolers and engine cooler combination oil for gm applications

derale transmission coolers and engine cooler standard mount combination oil for gm applications

derale transmission coolers standard mount d15903

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Feature Breakdown: Derale Combination Transmission and Engine Oil Cooler for GM Applications

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17" Wide x 12-1/2" tall x 3/4" deep, tube-fin cooler improves your vehicle's overall performance by ensuring proper fluid temperatures for both its engine and transmission with one compact system. Great Prices for the best transmission coolers from Derale. Derale Combination Transmission and Engine Oil Cooler for GM Applications part number D15903 can be ordered online at etrailer.com or call 1-800-940-8924 for expert service.

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Derale Transmission Coolers - D15903

17" Wide x 12-1/2" tall x 3/4" deep, tube-fin cooler improves your vehicle's overall performance by ensuring proper fluid temperatures for both its engine and transmission with one compact system.

Features:

Keeps both engine and transmission cool with just 1 system
- Engine oil and transmission fluid flow through separate tubes inside the same core for effective, simultaneous cooling
Improves functioning and overall performance of transmission and engine
Extends life of both transmission and engine and prolongs period between necessary fluid changes
Cuts down on heat-related failures
Designed with copper tubing expanded into aluminum fins for maximum heat transfer
- Copper is the best material for conducting the heat out of the fluid while aluminum is ideal for transferring and dissipating that heat
Protected from possible damage during installation by plastic fin guards and powder coat finish
Includes:
- Thermostatic sandwich adapter to provide external oil lines
- 13/16-16 Sleeve nut for GM applications
- High-temperature, OEM spec hose with stainless steel clamps
- Nylon mounting rods with pads
- Bendable, metal mounting brackets
- Insta-dapt radiator adapter
- All necessary hardware
Made in USA

Specs:

Inlets: 11/32" hose barb
Dimensions: 17" wide x 12-1/2" tall x 3/4" deep
Engine filter thread size: 13/16"-16
1-Year warranty

15903 Derale GM Combo Transmission and Oil Cooler with Installation Kit

Installation Details D15903 Installation instructions

4.2

17 reviews

5 Stars		(8)
4 Stars		(6)
3 Stars		(2)
2 Stars		(1)
1 Star		(0)

by: Brian 01/31/2018 One Year Later

Tranny side had no problems. Oil side kept leaking and was eventually disconnected. Hose clamps for hoses need to be replaced with sealed units.

by: Thomas 03/01/2018

The kit is excellent, with a great price. I haven’t installed it yet. The kit doesn’t include the reducer for the smaller hose. Fast shipping and great support. Detailed Instructions would be extrodinarilly helpful.

by: Charles 12/18/2021

The customer service is excellent thanks for the product. It is exactly as on the web site. Installing it on my truck. Honest, honorable people. I will continue to do business with. Thanks again

by: Brian 07/22/2025

Fast shipping

by: Dave B 02/10/2018 One Year Later

Without a video for my 2014 explorer and with limited written instructions I chose to find a repair shop that would do the installation. It cost me $360 to have the dual cooler installed. Most places won't consider third party parts to install and others that wanted to charge from $600 - $800 to install. Removing the front cowling, bumper, & headlights proved to be too big of a challenge without adequate instructions. Also following the installation I drove cross country pulling a trailer and I didn't trust my self with the work, and at near 70 years I no longer want to tackle such a job. Other than above I made it to California with out incident.
PS, it would have been helpful for an estimate of the additional engine oil and transmission fluid it would take to fill the new system.

by: Dan 09/15/2015

This is a good product and installation was fairly straight forward. The directions do not address the transmission connection to the cooler. If it did, someone would have realized a part was missing from the kit. If you are installing this cooler on a Dodge you will need a different connector than the one provided. Dodge uses a snap in, rather than screw in, connector for the transmission line. I only discovered this by watching a video online which actually gives the Derale part number for the connector (I don't remember what it is). I explained this to the customer service agent and he did not believe me nor would he send me one for free. Since I ordered this kit specifically for a Ram I feel this adaptor should have been included in the kit. Disappointed about that, otherwise it seems like a good kit. I haven't tested it yet since I am waiting for the adaptor.

by: Morris 07/03/2022

Package was delivered on time. Installed it the next day. Didn't realise it's for oil and transmition. Just needed the oil cooler. Either way it's installed. Took a bit as I mounted in a different location than in front of radiator. Only did the oil. Already have a trany cooler. However I might loop into the other side for a trany and use the whole radiator. So far so good

Morris One Year Later

7/4/2023

1 year later and still going strong. It does make a difference but have t measured the temp. However, pulling a 32 foot travel trailer I do notice a difference when I turn the fan on

by: D. MacKenzie 03/23/2016 One Year Later

I installed the etrailer derale transmission cooler on my 2012 Toyota Tacoma. Hauled home a 3500lb tractor 3000 miles up hilly terrain and had no problems at all. Works great.

by: SB 07/13/2015

I have not had a chance to install this unit yet. From the looks of it though it is worth it. Install should be a breeze too. I purchased this for a 05 Dodge Caravan. It cam with all the different oil filter adapters color coded for the filter you use.

Chris D.

11/29/2015

How was the install? Are you happy with it? Any things you wished you knew before you began the install?- thanks. - getting ready to do the same

by: Dave H 04/03/2016

Easily installed to an 05 town and country. I think the 3/8 compression/ barbed fittings should be included in the kit though. Also do yourself a favor and make sure you get the hoses on the cooler before you tie it in place cause they go on HARD. Otherwise pretty simple. Installing for towing purposes. Took about 1 hour complete.

by: Karyn Ellis 06/25/2016

I haven't had the transmission cooler installed yet but the service I received in ordering and the shipping was way above what I ever expected. Very friendly customer reps and they know their job.

by: Leslie L 08/24/2018

This cooler does a good job keeping transmission oil engine oil cooler.

by: Russ C. 11/15/2016

Everything arrived intact, no damage. Instructions were clear. Products were put on with ease. Thanks

by: Surjit 03/25/2025

Very helpful,

by: jeff s 04/21/2017 One Year Later

This kit was easy to install on my application and works very well.

by: Victor 02/23/2016

Received it packaging was great the cooler was in perfect condition all items seem accounted for. Cant wait to install it.

by: David 11/05/2021

true

See what our Experts say about this Derale Transmission Coolers

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Info for this part was:

Updated by:

DeAnne T

Updated by:

Wilson B

Updated by:

Daron K

Expert Research:

Patrick B

Expert Research:

Jameson C

Expert Research:

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Installed by:

Andy C

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