Keeping coolant and transmission temps under control when towing in the summer heat

[thompsoj22]

Routing the transmission cooler direct is a good idea, but my worry with that is for the winter when there is benefit to warming the fluid a bit from cold. But, I could also add a thermostatic control valve in the circuit, I suppose.

Fans are still programmed to come on at the factory temps. I bought the 700w fan motor for the drivers side, along with the correct fan blade, and will install both this weekend.

Thanks for offering some good ideas.

As i have had to tweak this upgrade "twice", I have found that you can R&R the drivers side fan/motor assy without dumping the coolant. Simply remove the fan support upper bolts and lean the shroud aft, This will give you enough room to remove the fan snap ring and fan and then the 3 fan motor bolts and re'assemble in reverse order without dealing with the coolant. Use "extreme caution" with your tools in the radiator area as "any" comtact with the radiator fins will dent/damage your "beautiful new radiator". The passenger side is "doable" also but i dont advise it, It is just to tight and you will dent the radiator fins. But you now have a draincock, What a great idea! Any GMC design engineers/FST reading this now?

 

[Geotrash]

As i have had to tweak this upgrade "twice", I have found that you can R&R the drivers side fan/motor assy without dumping the coolant. Simply remove the fan support upper bolts and lean the shroud aft, This will give you enough room to remove the fan snap ring and fan and then the 3 fan motor bolts and re'assemble in reverse order without dealing with the coolant. Use "extreme caution" with your tools in the radiator area as "any" comtact with the radiator fins will dent/damage your "beautiful new radiator". The passenger side is "doable" also but i dont advise it, It is just to tight and you will dent the radiator fins. But you now have a draincock, What a great idea! Any GMC design engineers/FST reading this now?

Thank you, John. That's timely and helpful info. I'll be tearing into this project this evening.

 

[Foggy]

My mishimoto has a draincock on the lower left(driver) side...
It seems like great idea, but I'm not sure how I'd ever get to it to
use it. It does have an anode built into it.. so that may be it's only purpose,
because to use it as a drain would be be very difficult at best

 

[2007YukonXL]

>After reading a bunch of posts from all of you, especially @kbuskill's experience with his Cold Case,

Where oh where is the @kbuskill's experience with his Cold Case thread??? I tried a search of all of his posts...that dude sure knows his hitS on this SUV...I learned everything about the SUV from stem to stern but I could not find the post on the modifications to do the Cold Case install...so I am man enough to admit...

!!!Oh @kbuskill PLEASE HEP Me Out Bro!!!

I got to the part where I am sliding the radiator into the core support and hear "clunk". After dropping the appropriate number of F-Bombs on the target I thought I would throw out a life line and ask the forum where exactly do I cut away on the truck to get the radiator to fit.

While I wait for a response I will try to squeeze up between the core support and the engine to see if I can locate the areas of the truck to "massage".

 

[kbuskill]

>After reading a bunch of posts from all of you, especially @kbuskill's experience with his Cold Case,

Where oh where is the @kbuskill's experience with his Cold Case thread??? I tried a search of all of his posts...that dude sure knows his hitS on this SUV...I learned everything about the SUV from stem to stern but I could not find the post on the modifications to do the Cold Case install...so I am man enough to admit...

!!!Oh @kbuskill PLEASE HEP Me Out Bro!!!

I got to the part where I am sliding the radiator into the core support and hear "clunk". After dropping the appropriate number of F-Bombs on the target I thought I would throw out a life line and ask the forum where exactly do I cut away on the truck to get the radiator to fit.

While I wait for a response I will try to squeeze up between the core support and the engine to see if I can locate the areas of the truck to "massage".

I didn't massage the core support at all.

I trimmed the sides of the upper radiator mounts to fit under the core support.

This is the only pic I can find...

The only other thing that required trimming was the fan shroud to allow it to sit flush against the radiator.

And don't forget to add a restrictor in the surge tank port on the radiator.

Here is a link to the post in my build thread where the radiator was installed...
https://www.tahoeyukonforum.com/thr...rb-ltz-mod-thread.100141/page-84#post-1524668

Hope that helps.

 

[2007YukonXL]

Nice THANKS so much for the advice.

I got it installed and am pretty happy.

 

[thompsoj22]

Geeze, Coldcase is a tight fit!

 

[Geotrash]

Update: got a Derale 13960 on the way that I’ll mount below the bumper in the space behind the lower grille. This will hopefully solve the problem of the Trucool reducing airflow through the radiator and with the cold case radiator, keep both my transmission and coolant temps low when towing in 90°+ heat this summer.


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[thompsoj22]

Update: got a Derale 13960 on the way that I’ll mount below the bumper in the space behind the lower grille. This will hopefully solve the problem of the Trucool reducing airflow through the radiator and with the cold case radiator, keep both my transmission and coolant temps low when towing in 90°+ heat this summer.


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just a couple pic's for some mounting ideas. The hinges that mount from the back of the sub bumper to the top of the DERALE allow infinite angle adjustment to get it as close to the ram air of the lower grill opening, They also allow for a front impact with an obstacle and possibly survive by allowing the cooler to swing back without breaking.

View attachment 277006

 

[Geotrash]

just a couple pic's for some mounting ideas. The hinges that mount from the back of the sub bumper to the top of the DERALE allow infinite angle adjustment to get it as close to the ram air of the lower grill opening, They also allow for a front impact with an obstacle and possibly survive by allowing the cooler to swing back without breaking.

View attachment 277000 View attachment 277001 View attachment 277002 View attachment 277006 View attachment 277007 View attachment 277008

Fantastic! Thank you! You addressed several of the questions in my head, including how you modded the lower grille for airflow. Your timing is perfect as well - I’ll be installing the Derale this weekend.

Where did you end up tapping in for power? And did you have hoses fabbed up or use the ones that came with the unit?

 

[Foggy]

I just got mine installed... I mounted the top of it like you did to the metal inner
bumper.. I used the license plate holes to secure the bottom of it..
Just got some M5 x 60 mm ss screws and nut from HD.. and used plastic/rubber
spacers to get the right distance.
When I ordered mine, I didn't realize it came with hose/fittings so I ordered them..
I do like the 3/8 compression x hose barb derale AN looking aluminum fittings better
than the brass 3 piece ones that came in the kit..
But you won't need anything else to mount it if you don't want to.
I didn't use the inline thermostat to control it...
I just installed a rocker switch by my console to turn it on when I want to

 

[Geotrash]

I just got mine installed... I mounted the top of it like you did to the metal inner
bumper.. I used the license plate holes to secure the bottom of it..
Just got some M5 x 60 mm ss screws and nut from HD.. and used plastic/rubber
spacers to get the right distance.
When I ordered mine, I didn't realize it came with hose/fittings so I ordered them..
I do like the 3/8 compression x hose barb derale AN looking aluminum fittings better
than the brass 3 piece ones that came in the kit..
But you won't need anything else to mount it if you don't want to.
I didn't use the inline thermostat to control it...
I just installed a rocker switch by my console to turn it on when I want to

Awesome, thank you Foggy.


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[Foggy]

Got the tap talk app. Here's some pics, hopefully

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[Geotrash]

Got the tap talk app. Here's some pics, hopefully

Sent from my KYOCERA-E6560 using Tapatalk

Nice! Great pics, thank you. Looks clean.

 

[thompsoj22]

Fantastic! Thank you! You addressed several of the questions in my head, including how you modded the lower grille for airflow. Your timing is perfect as well - I’ll be installing the Derale this weekend.

Where did you end up tapping in for power? And did you have hoses fabbed up or use the ones that came with the unit?

The oe fuel pump fuse is not used in 08 and other years so i used a fuse tap and got ign on pwr there, The picture is bad but i used two 90 degree fittings to turn the lines and get them headed laterally towards the trans line connections. This aviods hacking the fascia impact foam. I did use the included ferrel line connections with success and no leaks whatsoever. Once again IMO you should try the cooler as a standalone and eliminate the radiator from the circuit. I am still running the radiator "pre heater" and feel it has a negative effect in the summer.

 

[Geotrash]

The oe fuel pump fuse is not used in 08 and other years so i used a fuse tap and got ign on pwr there, The picture is bad but i used two 90 degree fittings to turn the lines and get them headed laterally towards the trans line connections. This aviods hacking the fascia impact foam. I did use the included ferrel line connections with success and no leaks whatsoever. Once again IMO you should try the cooler as a standalone and eliminate the radiator from the circuit. I am still running the radiator "pre heater" and feel it has a negative effect in the summer.

View attachment 277013 View attachment 277014 View attachment 277015

Once again, thank you. Very helpful. I ordered a fuse tap just now, and will take the same approach.

 

[RooTBeeRthe1st]

I have the cold case in my cart...
probably get in next pay check.

Also been running the Tru-Cool Max Transmission Cooler HD LPD4739 in front of the rad, might have to swap it for the Derale+fan when I have to fit my whipple intercooler behind the grille.

Glad I found this thread!

 

[Sparksalot]

I have the cold case in my cart...
probably get in next pay check.

Also been running the Tru-Cool Max Transmission Cooler HD LPD4739 in front of the rad, might have to swap it for the Derale+fan when I have to fit my whipple intercooler behind the grille.

Glad I found this thread!

The folks here are GOOD at helping spend your money.

 

[Geotrash]

Got the cooler installed today. I took your advice, John, and deleted the "cooler" in the radiator from the loop. I see that's the way Tom did it as well. The only problem I ran into was getting switched power. The #20 fuel pump fuse spot on my truck doesn't have power, even when the engine is running, so I ended up using an unswitched fuse (for the sunroof/roof light bar - it's a 30 amp circuit) in the block and using the fuse tap for that circuit. Not ideal, but unless anyone has a another idea for a switched circuit with the 5 amp capacity I need I can tap into, I'll roll with it for now. The cooler's thermostat is wired into the circuit so I shouldn't have any problems with parasitic drains.

Going to be towing in the mountains this weekend, so we'll see how it goes! I'm happy to have the Trucool 40K out from in front of the radiator.

 

[Geotrash]

A couple more showing the mounting and wiring from the bottom. I have 2 more straps that will attach to the bolts that hold the skid plate on.