The last mod I'd like to get completed on my new passenger van is the installation of an inline aux trans cooler (in addition to the small factory one).

I'm looking for recommendations for one that will fit nicely in front of the radiator and one that I can use aftermarket fittings with that prevent any splices or cuts to the OEM lines.

The van hasn't seen trans fluid temps in excess of 193 degrees yet on several trips we've made so far towing our 7600# GVWR trailer. But with an Alaska trip planned for next year, I want the re-insurance of cooler temps in the mountains.

Etrailer has 3 Derale coolers, 13502. 13503, and 13504 that come up as a direct fit. The biggest is 13504 at 12 inches tall. They all have the same width of 11 inches wide. Only an inch difference in height between the 13502 and 13503. I'm thinking the 13503 is a good size to augment the the OEM cooler. The largest one, 13504, may be for vehicles that have no OEM cooler.

Etrailer also suggests this: "The only extra adapters you will need to install the transmission cooler on your vehicle will depend on what 6.0L engine size you have. If you have the 368 cubic inch engine you will need the Derale Radiator Adapter Fittings for GM # D13018. If you have the 364 cubic inch engine you will need the Derale Snap-In Radiator Adapter Fitting for GM # D13035. These adapters allow you to connect the transmission cooler to your vehicles radiator without cutting or flaring of lines."

I'm unsure which set of adapters I would need, if I would need any at all.

Any help or recommendations is appreciated.

 

I've used a Long Tru-cool LPD 4590 on past vehicles and it worked really well.
It's a 24,000 BTU unit with a low pressure bypass. Around $100. Came with everything needed, and installed in less than an hour.

https://www.trucool.com/products/tru-cool-lpd

I haven't put one on my Savana because the factory cooling works well enough, but I don't have a 3500.

 

One 13018 kit is for a lineset that threads into the radiator. The 13035 is for a radiator that uses snap-rings to hold in the transmission lines. If you look at the 13035 photos they show how you make the connections...you jam the hose barb into the radiator and then slip the hoses over the new hose barb and the existing line so that you retain use of the original cooler and add the new cooler. You will need to pop the hood and look at the passenger side of the radiator to see what you need. The driver's side fittings are for an engine oil cooling system.

 

I added a transmission cooler to my 2017 Express after towing our 6000# camper through the Rockies a couple years ago in 100 degree heat. My transmission temps spiked at over 230 degrees. I installed a Tru-cool LPD49211 behind the grille and in front of the radiator in place of the factory transmission cooler. No adapter fittings were necessary. I just unclipped the transmission fluid lines from the old cooler and ran hose to the new cooler using the hose and clamps included with the tru-cool cooler. Mounting brackets are also included with the tru-cool cooler. Pretty straightforward install. No cutting or flaring or adapters required. Figuring where to mount the cooler and which lines were which was the toughest part.

 

We have a 2015 4500 Express under a class C RV. With our Jeep in tow, we're right about 20k pounds. I have been looking for a larger trans cooler and have struggled between replacing the existing cooler or just adding a second cooler mounted in the area above the factory unit. For those with such experience, which way is recommended. Pictured below is the existing cooler.

 

Add a second one.

https://static.summitracing.com/glob...er_techdoc.pdf

 

One thing to do before buying parts: measure what you already have.

My 2010 2500 with a 4.8 and 6L90E, I planned to upgrade to a B&M 70268.

Unboxing it, it was pretty close in size to the OEM cooler. So it wasn't worth the effort to install. I don't run heavy and rarely tow. So I resold it. If you're gonna upgrade, make sure it's an upgrade first.

 

He's right. I have a 5.3L with 4L60E. I monitored my ATF temps while offroad and crawling up a lot of steep hills, and the factory cooler managed just fine.

 

We have a few hills in the area so I hope to do some "test" pulls next week with the rv loaded and the Jeep in-tow. Perhaps what's there now is adequate but that fuzzy coil thing just doesn't look like much! .
Gary

 

Yeah, totally test it. Cheap knowledge. I give GM a lot of crap. But for the g-series I own, it's pretty stoutly built.