• If you currently own, previously owned or want to own an Avalanche, we welcome you to become a member today. Membership is FREE, register now!

Aux Transmission Cooler Upgrade & Relocation

ToyHauler13

SM 2024
SM 2023
SM 2022
Full Member
Joined
Oct 29, 2021
Messages
498
Location
West of Chicago (but not far enough)
First, giving a shout out to @JohnnieMo (not active since 2019) for this placement idea for a larger trans oil cooler.

I've been working on and off this winter selecting a cooler and the other parts required then fabricating what was needed to mount the new cooler. Got a few days of decent temps this week to get it installed.

Cooler is a 50K BTU, 30 row plate unit. Core is roughly 12 X 8.5 X 2 inches.
I went with 6-AN fittings for the hoses.

IMG_5666.JPG

I used some Uni-Strut I had for the mounting support since it fit the cooler so well and to me looked a little better than flat stock.
IMG_5667.JPG


Never worked with AN fittings and I liked it!
IMG_5668.JPG


I cut out the flat area where the license plate mounts. Went to the U-Pick-It and looked at 200 cars and trucks for a suitable grill to use. Not many front ends of vehicles still intact. Did find something off a Mazda that I liked. I cut the center portion of that grill to fit and mount in the new opening in the bumper. Painted it with the matching paint code spray paint I had left over.
IMG_5661.JPG


3/8" hard line compression fitting to 6-AN. Cut keeping as much metal line yet still keeping good access to the fittings. With an extra 45 deg fitting I also made a hose to connect to the supply hard line AN fitting (lower one in the picture). I'll open it for when I replace the trans fluid and filter this summer for pumping out the old fluid.
IMG_5683.JPG


Mounted between and held in place with one of the tow hook bolts on each side.
IMG_5684.JPG

IMG_5685.JPG


The bottom of the cooler will be held in place with a small nut/bolt to the bottom edge of the bumper (not done yet in this picture). I think I will grease the top bracket at the tow hook bolts and just snug it up a little instead of full tight. I'm thinking if I rub the bottom edge or hit something in the road the cooler will pivot back as much as the bottom edge of the bumper does and hopefully preventing cooler damage.
IMG_5691.JPG




I'll probably block off much of the cooler in the winter. No leaks so far!
IMG_5690.JPG
 
Very nice!
But man that cooler is just asking to get damaged. And no air flow unless moving.

Why not in front of the condenser?? My 40k tru-cool fit nicely there.

Either way nice work and looks good. What brand or model cooler is that?
 
Very nice!
But man that cooler is just asking to get damaged. And no air flow unless moving.

Why not in front of the condenser?? My 40k tru-cool fit nicely there.

Either way nice work and looks good. What brand or model cooler is that?

Thank You!
I know, I know! I spent a month going back and forth on where I wanted to put one. Laid awake many nights considering different coolers and locations.

The problem is I am putting a large intercooler in front of the condenser. Actually the new intercooler and circulating pump can be seen in the last picture. Figured I would get that mounted up while I had the front cover off and not have to take it off again later.

I could have stuck with the small OEM trans cooler which would stay between the condenser and the new intercooler, but I wanted a larger trans cooler. Also, even if I could have squeezed a larger trans cooler behind the new intercooler (which is now adding more heat to that airflow) I really didn't want to dump even more heat from larger trans cooler into the airflow to the engine radiator. If all I was doing was to install a larger trans cooler it would have gone right up front like you and others have done....no problem with that at all! There was no place I could find up higher in some airflow that would work for a larger one.

Agree about no airflow unless moving. My trans temps before would raise 30-40 degrees from highway to sitting in traffic in hot weather. Even with the radiator fans on I doubt there is much air flow through that little OEM cooler to do much while not moving. I think with this larger cooler and mounted down there with things being more open and maybe cooler air in general at idle, it will just radiate more heat (as certainly does the Tru-Cool) than the OEM when not moving. Yesterday I did about a half hour of stop and go driving returning a bad battery to get my core deposit and to check for leaks again. Between lights I'm doing 45 mph. Outside temp was around 42 (warm!). Never got the trans temp past 95 degrees. I know under similar conditions (winter) it was closer to 150 degrees with the stock cooler. So, I think it is going to dissipate much more heat at idle than the OEM setup which is an improvement. Don't think I'll need to at all, but I can always add a fan behind it that could be switched on if necessary.

I did think a lot about how I could protect it better. Wouldn't be as much of an issue if my front end was as high as yours (just love your truck)! I can't remember ever having anything really hit that area in any other vehicle I've had other than bugs and small stones. I've managed to avoid most things coming at me. I've probably been very lucky! I'm recently retired but I did field service work for 30 years and have driven a lot of miles during that time. Most of the miles I now put on this truck will be pulling the camper, not even that much local driving and not any commuting to work anywhere now. Driving less should reduce the chances of having a direct hit with something.🤞 At least that's what I'm telling myself so I can sleep at night.

At first I thought this cooler was one specific brand but then noticed it also from many other sellers. I really like this one even after seeing it up close and in my hands. Only offered with 10-AN inlet/outlet then you add the supplied 6-AN or 8-NA reducer. I think you can get a barbed to AN adapter too if one wanted to avoid AN entirely. This cooler comes in many sizes from 13 to 34 rows. It's on Amazon and eBay. Evil Energy and G-plus were two of the bigger sellers. Got the cooler here: https://www.ebay.com/itm/334581603188 Got the Evil Energy hose and AN fitting kit on Amazon.
 
That makes sense now. I would want it in a different spot too if I had plans for an intercooler in front of the radiator. It's definitely much better that that puny excuse for a trans cooler they install at the factory. That thing is a joke. You did a very nice job with the all the work as well.

Did the intercooler not fit where you have the new trans cooler?
 
What you putting in there? I am looking at something for my new 408cc lq4 motor that has stage 3 blower cam. Would like to see how much room that takes and what it cost you for the blower assembly. Also what did you do for injectors and fuel system?
Are you upgrading to a 4l80e or 6L90e?

I am looking at a Tom Demuse Adapter kit, Magnuson Tub and Edlebrock 2650 blower. Cost is about $4500 for basically what you have in your picture. Still would have to get injectors and upgrade the fuel system to support it. Probably will do a 4l80E in my truck although if I can figure out how to use a 6l90E I may go that route.
 
Last edited:
What you putting in there?
A Whipple 2.3L for the '07-'13 LS engines. You can check out all they have to offer. A lot of complete systems and LS universal systems.

This system is 100% complete. Everything you need down to the zip ties. I'm very impressed with the completeness and quality of parts. Intercooler and pump up front, blower, heat exchanger and intake (pictured) all hoses for coolant and fuel, new fuel rails, new high flow fuel injectors, new NGK Iridium plugs one heat range lower than stock, wiring harnesses etc. etc. Fuel pump is adequate since this is a Flex Fuel version.
You get a little flash tool to send them your stock program then they send the new file/program to flash to the ECM before starting things up.

I have a 2013 with the stock 6L-80e. It should be fine, 107K miles. Don't plan on consistently abusing it and that's why I did the trans cooler relocation and soon a fluid and filter replacement.

This system lists around $7100, $250 for shipping and no tax added. I bought this on Black Friday and it was $1100 less.

Yours sounds pretty interesting!
 
Last edited:
Back
Top