Ready to pull trigger on Derale trans cooler - need advice

[DaveO9]

I'm a little overwhelmed with all the different Derale options. And their website is not super helpful to gain understanding of nuances between model numbers.

I've seen many instances of users here, including @Geotrash, using the 13960 kit. Amazon gives me a Does Not Fit warning with that one, but it gives me the green light for the 13950 kit instead. Does anyone know the difference? the 950 kit is a little cheaper too.

I've also considered the Electra-Cool instead of the Atomic-Cool - the description for that one says medium - heavy towing which should be more than enough for me. But it does have a bit higher amperage draw than the Atomic, so that's a consideration. And I'm also having similar exact model number confusion for the electra, and distrust in Amazon's fitment guide.

Basic question: we have 6-an fittings on our coolers, not 8-an, correct? That would help me narrow things down a bit.

 

[Geotrash]

The 13960 is 46,000 BTU versus 22,000 BTU for the 13950, so it has a little more than double the cooling capacity. Amazon’s configurator has no idea because none of them are direct fits for our vehicles and require some plumbing and mounting work.

You can use 6AN fittings if you want to, but our trucks don’t have those fittings from the factory. So it takes some adapting.

 

[DaveO9]

The 13960 is 46,000 BTU versus 22,000 BTU for the 13950, so it has a little more than double the cooling capacity. Amazon’s configurator has no idea because none of them are direct fits for our vehicles in require some plumbing and mounting work.

You can use 6AN fittings if you want to, but our trucks don’t have those fittings from the factory. So it takes some adapting.

Perfect, thanks. I was pretty sure the Amazon configurator was bogus, it was just weird that some said they fit, others didn't. I downloaded the Derale .pdf full catalog, that helps too. I also found a configurator on their website, which actually recommended the 13950 for my '13 5.3 Tahoe, so I'm probably going to go with that. I don't plan to ever tow much more than 3-4k.

Now, my next question. Where to install this thing in a Tahoe without the lower grill/open area that the GMC guys have. WA state requires a front license plate, so not an option to create a new opening there. There are openings in the fascia for the tow hooks, maybe those would be good enough.

I found another thread that opened with the exact question I have, but there was no follow up regarding the final solution: https://www.tahoeyukonforum.com/threads/transmission-cooler-mount-options-in-a-tahoe.135592/

 

[gooffeyguy]

Do you have an external OE trans cooler in front of the radiator already or just the one in the side of the radiator?

 

[Geotrash]

Do you have an external OE trans cooler in front of the radiator already or just the one in the side of the radiator?

This is a good point. In my opinion and after much experimentation, the factory external cooler setup is truly optimal for these trucks.

 

[Trey Hardy]

I'm a little overwhelmed with all the different Derale options. And their website is not super helpful to gain understanding of nuances between model numbers.

I've seen many instances of users here, including @Geotrash, using the 13960 kit. Amazon gives me a Does Not Fit warning with that one, but it gives me the green light for the 13950 kit instead. Does anyone know the difference? the 950 kit is a little cheaper too.

I've also considered the Electra-Cool instead of the Atomic-Cool - the description for that one says medium - heavy towing which should be more than enough for me. But it does have a bit higher amperage draw than the Atomic, so that's a consideration. And I'm also having similar exact model number confusion for the electra, and distrust in Amazon's fitment guide.

Basic question: we have 6-an fittings on our coolers, not 8-an, correct? That would help me narrow things down a bit.

I’ve had good luck running tru cool 40k trans coolers their cheap make a considerable difference in temperature over a stock one
And mounts in the stock coolers location behind the grill

I couldn’t find the pic of the one I put on the Tahoe but here’s a pic of the one in my old Silverado
In that truck it took my temps from 210 give or take all the way down to 165-175 and that’s without a fan on it I’m sure if you put a cooling fan on there it would be even lower

 

[DaveO9]

Do you have an external OE trans cooler in front of the radiator already or just the one in the side of the radiator?

No. I just have the radiator cooling.

This is a good point. In my opinion and after much experimentation, the factory external cooler setup is truly optimal for these trucks.

Do you recommend doing the retrofit of an OEM cooler over a Derale? My '09 Tahoe had the factory cooler, and although I didn't tow much, it didn't seem to do a stellar job of keeping the trans cool. It would go over 200 on mountain passes w/o towing and I remember the few times I did tow it got up to 230. Nevertheless, you've obviously done a lot of research and experimentation, so I'd welcome and strongly consider your advice. Thanks.

 

[DaveO9]

I’ve had good luck running tru cool 40k trans coolers their cheap make a considerable difference in temperature over a stock one
And mounts in the stock coolers location behind the grill
View attachment 426729I couldn’t find the pic of the one I put on the Tahoe but here’s a pic of the one in my old Silverado
In that truck it took my temps from 210 give or take all the way down to 165-175 and that’s without a fan on it I’m sure if you put a cooling fan on there it would be even lower

I purchased a tru-cool a while back but then returned it. I had the same concern others on here have had regarding how much of the radiator it covers up and possible degradation of engine cooling. Have you noticed any issues with that with your installs?

 

[Geotrash]

No. I just have the radiator cooling.

Do you recommend doing the retrofit of an OEM cooler over a Derale? My '09 Tahoe had the factory cooler, and although I didn't tow much, it didn't seem to do a stellar job of keeping the trans cool. It would go over 200 on mountain passes w/o towing and I remember the few times I did tow it got up to 230. Nevertheless, you've obviously done a lot of research and experimentation, so I'd welcome and strongly consider your advice. Thanks.

Thanks for that. It’s worth noting that my experiments have been to handle towing at the limits in hot weather in the mountains, which probably 95% of owners of these trucks will never do. Even at that, I would have no qualms about keeping the factory external transmission cooler, in hindsight.

The main misconception I see from folks is to worry about transmission temperatures that are well within the normal range, per GM powertrain engineers. 200-235 driving up a mountain pass is normal and easily within the limits of Dexron VI fluid. Most of the time your fluid will be below 200 anyway for daily driving. Some folks offset this with more frequent fluid changes. I personally use 25K miles as my change interval on my towing rig.

 

[Foggy]

Just for more info.. I did not open up my lower bumper/grill for my derale
with the fan. I figured I would IF Needed.. but haven't needed it.
It's at an angle anyway pointing down a bit. I didn't want to blow hot
air UP into the engine compartment. There's a decent amount of dead
air space in front of it.. When I turn on the fan it pulls nicely and cools
the trans 10-15* within a couple miles/minutes

 

[Trey Hardy]

I purchased a tru-cool a while back but then returned it. I had the same concern others on here have had regarding how much of the radiator it covers up and possible degradation of engine cooling. Have you noticed any issues with that with your installs?

No sir and I tend to drive my vehicles pretty hard especially on go home day

 

[DaveO9]

Thanks for that. It’s worth noting that my experiments have been to handle towing at the limits in hot weather in the mountains, which probably 95% of owners of these trucks will never do. Even at that, I would have no qualms about keeping the factory external transmission cooler, in hindsight.

The main misconception I see from folks is to worry about transmission temperatures that are well within the normal range, per GM powertrain engineers. 200-235 driving up a mountain pass is normal and easily within the limits of Dexron VI fluid. Most of the time your fluid will be below 200 anyway for daily driving. Some folks offset this with more frequent fluid changes. I personally use 25K miles as my change interval on my towing rig.

Thanks. Yeah I’m starting to understand about the higher temps allowed with Dex VI. I’ve pretty much decided to go with an OEM retrofit cooler now. Looking at options for the cooler itself and the new line I’ll need between it and rad. Not sure if I’ll do the full line replacement or do some retrofitting to existing lines between trans and rad.

 

[Geotrash]

Thanks. Yeah I’m starting to understand about the higher temps allowed with Dex VI. I’ve pretty much decided to go with an OEM retrofit cooler now. Looking at options for the cooler itself and the new line I’ll need between it and rad. Not sure if I’ll do the full line replacement or do some retrofitting to existing lines between trans and rad.

A wise choice, I think. The good thing about the factory lines is that there aren't any places where you'll need to use clamps, which reduces the chances of a line popping off a fitting later.

 

[mikez71]

Thanks. Yeah I’m starting to understand about the higher temps allowed with Dex VI. I’ve pretty much decided to go with an OEM retrofit cooler now. Looking at options for the cooler itself and the new line I’ll need between it and rad. Not sure if I’ll do the full line replacement or do some retrofitting to existing lines between trans and rad.

I went with replacement lines so I wouldn't have to mess with hose clamps. Also figured the original hoses have some mileage on them.
Straightforward job, probably need to put the truck on stands to get space to snake the lines through there, but otherwise super easy and fairly cheap..

Lines costed a little over $100..

Amazon.com

Amazon.com

I went with a TYC brand cooler from Rockauto for ~$60. Was made in Taiwan (the country!) and it looked well made and was well packed.

 

[89Suburban]

Thanks. Yeah I’m starting to understand about the higher temps allowed with Dex VI. I’ve pretty much decided to go with an OEM retrofit cooler now. Looking at options for the cooler itself and the new line I’ll need between it and rad. Not sure if I’ll do the full line replacement or do some retrofitting to existing lines between trans and rad.

Is there a part number for the cooler? Is it direct bolt in? Any fasteners need purchased as well?

 

[DaveO9]

I went with replacement lines so I wouldn't have to mess with hose clamps. Also figured the original hoses have some mileage on them.
Straightforward job, probably need to put the truck on stands to get space to snake the lines through there, but otherwise super easy and fairly cheap..

Lines costed a little over $100..

Amazon.com

Amazon.com

I went with a TYC brand cooler from Rockauto for ~$60. Was made in Taiwan (the country!) and it looked well made and was well packed.

Thanks. Yeah, I saw some other posts that made it sound like installing the lines was a real bear. Glad to hear another perspective that said it wasn't so bad. Do you have 4wd? If so did you remove the front driveshaft?

Is there a part number for the cooler? Is it direct bolt in? Any fasteners need purchased as well?

Here's the part number for the GM Genuine cooler: 20880895. And I think there's a bracket or clip for the lines by the cooler: 15049288.

 

[DaveO9]

All my parts on order for a factory style trans cooler, including cooler, line set from trans to rad/cooler, line from rad to cooler, and clip to hold the lines below the cooler. everything is genuine GM except the cooler itself. I went with a Dorman unit for that - couldn't justify the almost double $ for the GM one. Fingers crossed for decent quality, it got good reviews on Amazon. Thanks for everyone's input.

 

[Geotrash]

All my parts on order for a factory style trans cooler, including cooler, line set from trans to rad/cooler, line from rad to cooler, and clip to hold the lines below the cooler. everything is genuine GM except the cooler itself. I went with a Dorman unit for that - couldn't justify the almost double $ for the GM one. Fingers crossed for decent quality, it got good reviews on Amazon. Thanks for everyone's input.

Good deal. I have generally had good results with Dorman parts.

 

[89Suburban]

All my parts on order for a factory style trans cooler, including cooler, line set from trans to rad/cooler, line from rad to cooler, and clip to hold the lines below the cooler. everything is genuine GM except the cooler itself. I went with a Dorman unit for that - couldn't justify the almost double $ for the GM one. Fingers crossed for decent quality, it got good reviews on Amazon. Thanks for everyone's input.

What dorman cooler did you get? Can you please post pics of everything when installing with some tips and info that would help guide the rest of us wishing to to this?

 

[DaveO9]

What dorman cooler did you get? Can you please post pics of everything when installing with some tips and info that would help guide the rest of us wishing to to this?

Amazon.com

Dorman 918-213. I bought mine on RA, cheaper there, even with shipping.

And for sure, I will post pics of install to this thread. Might be a couple weeks out.