Tru-Cool Max 40k Transmission Cooler

[SUP SR]

About a week ago I was towing a 16ft trailer with a 2-seater Polaris Rzr loaded on it. I was driving from NM to AZ and it was freaking hot. Around 105 degrees. As I was driving, I saw a cloud of white smoke shoot out behind my Tahoe. I pulled off at the next exit and looked underneath as best i could since the ground was 120+ degrees. I found a large amount of oil on the passenger side and it looks like it got on the exhaust and that's what burned it up. I checked the oil filer and it was good. I checked the oil level and it was good. I limped it the rest of the way and made it to a shop. The oil underneath had dried up, but they came to the conclusion that it was tranny fluid that shot out of the overflow port. When they check the tranny fluid the mechanic said it was damn near boiling because it was so hot. He recommended I get an larger external trans cooler.

I've searched around on the forums and haven't seen much about external trans coolers. Just wondering if anyone has installed or has any good info about them.

Thanks

 

[SUP SR]

I just installed about a month ago a Trucool 40k on my 2002 Chevy Tahoe Z71, 5.3L (260,000 miles, first owner). I also had previously installed an instrument cluster from a 2001 Yukon Denali which has a transmission temperature guage. The result of the new transmission oil cooler has been a 40 degrees drop in temperature. Lately it as been around 100 F in the Houston area. My transmission temperature never goes above 150 degrees.

 

[Jlaughtr]

I just installed about a month ago a Trucool 40k on my 2002 Chevy Tahoe Z71, 5.3L (260,000 miles, first owner). I also had previously installed an instrument cluster from a 2001 Yukon Denali which has a transmission temperature guage. The result of the new transmission oil cooler has been a 40 degrees drop in temperature. Lately it as been around 100 F in the Houston area. My transmission temperature never goes above 150 degrees.

Did you bypass the radiator or just plug and play the new cooler and use the original trans cooler lines?

 

[ivin74]

Did you bypass the radiator or just plug and play the new cooler and use the original trans cooler lines?

When I did mine, I bypassed the radiator cooler.

 

[1BADI5]

The highest trans temp Ive seen since installing the 40k and deep trans pan is 140* when the heat index was right at 100*.

So with the larger cooler and trans pan I have about an additional 3.5 qts of DEX6 in the system now......it helps.

Key to GM transmissions lasting, especially if you're towing......fluid and filter every 30,000 miles of every 2 years. That's what I do and I have never had one fail on me......that also includes several 4L60s

 

[Jlaughtr]

Probably going to get this hose kit. Dont know about his bracket system. I like the 1 piece top bracket kit from the guy on the performance truck forum.
https://www.glennsautoperformance.c...tainless-transmission-line-set-99-07-gm-truck

 

[Jlaughtr]

good video of the Glenn's Auto Performance hose and bracket installation

 

[SUP SR]

Did you bypass the radiator or just plug and play the new cooler and use the original trans cooler lines?

I used the original lines and connected the cooler to them using the rubber hoses provided. Also attached the cooler by just drilling a couple of holes and using the small brackets provided. No need to buy additional brackets. Installed it with the input and output on top.

 

[Tim907356]

I hope you don't mind a post, but I just installed a TC 30K cooler, because it fit better between the beams, behind the lower grill. I left the rad. and external coolers in place, and plumbed it in series with the hose they provided; just cut the factory aluminum line and clamped the hose to the open ends. I still see ~160F on the gauge, but that's down from 185F in similar conditions.

I took mine in for service after that (flush and filter), and the guy said that one reason they overheat is b/c the torque converters go bad. I noticed with mine the transmission stutters off-idle, and over-rev's when it engages. Sometimes is a little rough at stoplights and such as well. Pulling a 5k# camper, I figured I'd just replace the TC, so its going in tomorrow....but with the 6sp., it's $1700!!

...sorry: 2010 Yukon Denali XL, 130k mi.

 

[latvius]

I used Glenns bracket on my Denali and the other one of that forum you referenced for my Tahoe, Glenns hands down is the better buy. The guy from the forum took forever with no communication and I thought it was supposed to come with the fittings maybe I was wrong on that part I don't remember well enough. What I do remember was wondering if I just gave my money away.
Glenns bracket comes with quality hardware and easy to install instructions. I used the compression fittings on both installs keeping the factory lines with the factory quick disconnects.
Expect to be about 30 degrees cooler running temps.