First of all Most everything not covered in this write up is covered in the following write-up:
https://www.jk-forum.com/forums/show...t=Transmission

After reading the whole write-up I found many people say how great it is on the highway but on low speed rock crawling there is not enough air moving past the cooler to make enough of a difference.


I started with the B&M 70268 transmission cooler. This type of cooler has many advantages:
They are tough, will not be damaged with flying pebbles on the highway or on the trail
They are more efficent than the older tube and fin style
They have a low temp bypass to help the tranny warm up faster.

and a 7.5" Spal pusher fan # 30100393





The fan fits if you rotate it so 2 of the 4 mounting holes are over the mounting plates of the cooler. I used 1/4" x .75" stainless steel bolts with nylon lock washers. With the weight of the fan I was not sure about only using 2 of the mounting holes so I looked to the other mounting area on the fan. They are used for different mounting tabs but if you take a 1/4" drill bit and drill a hole right through the center you can not only create another mounting point but one that is considerably stronger than the other thin mounting holes.



After you drill the hole place the fan on the tranny cooler and drill the 4 - 1/4" holes in the side paltes of the cooler. it is only aluminum so that will be easy. For the regular mounting holes I used 1/4" x .75" stainless steel bolts with nylon lock washers. For the other mounting I used Allan head 1/4 x 1.5" stainless bolts with nylon lock washers. Under the allan head I used stainelss washers but you need to cut a couple of millimeters of metal off of one side. please see picture:



It is easier than it sounds to grind down the washers. I placed the washer in a pair of vice grips and rubbed it on the cement until it was the desired shape. literally tool 20-30 seconds each.

For the bottom mounting brackets I did not trust the weight of the cooler and the fan to the brackets that cane with the kit so I went to Home depot and found some heavy gauge 90 degree brackets that worked perfectly. Any brackets would do I did trim them to make them fit better and block a little less airflow.



The home depot bracket attached perfectly to the bottom hole in the cooler. To add a little strength and rigidity I took one of the original brackets from the B&M kit and cut them so they were 2 holes long. I placed one under each angle bracket and put one 1/4 x .75" through the bracket the 2-hole piece of metal and the cooler. And I placed another of the same bolt through the other hole of the metal the cooler. (as seen in the photo above).

Because the cooler will need to be slanted back slightly you will need to place the angle brackets in a bench vice and flex them just a little. Here is what it looked like after I did that:





Here is how it looks from the back:



In some of the photos later it may look like the bolts are sticking way too close to the AC condensor but as you can see in the above picture they do not extend past the tranny cooler.

And from the other side:



Now you place the tranny cooler onto the frame rail and mark the holes to drill. I did 2 per bracket. You will use all 4 of the 1/4 inch sheet metal screws that came with the tranny cooler.




Now you need to make the upper brackets. Other write ups recommend using plastic mounting holes hanging off of the top frame rail but I thought with all of the added weight of the fan they may not be strong enough so I decided to bolt it directly to the upper frame rail.



To do that take 2 of the brackets that came with the cooler and bend them like this:



then cut the 2 top holes from the each bracket:



The lines on the brackets in the above picure shows exactly where to bend

Use 1/4 x .75" bolts with lock washers to attach the 2 lower holes in each bracket to the cooler. I used 2 again just to add a little rigidity.
Then using the brackets as a guide drill the 2 holes in the upper frame rail then screw in a 1/4 sheet metal screw in each.

Oh and you are going to want to attach the hoses and clamps before mounting because the mounting brackets will be in the way



Once mounted there is still about 3/4" between the cooler and the ac condensor:



You can refer to the other writeup for the instructions on installing the rubber hoses. the only addition i did here was use 3/4" split wire loom (that ribbed plastic tube with a cut down the long way for hiding wiring harnesses). it is all over the inside of the jeep so I figured if I used over the hoses it would look more factory and it would protect the hoses from most flying debris.

To wire the fan I used a relay and harness from painless wiring. Their instructions are so good there is no need to repeat.

Here is the finished product:




For some reason I used my hand again to prove there is plenty of clearance between the fan and the grille





Yeah I know I really need to paint the brackets!!!

 

Wow it came out nice. I was thinking about going a similar route but all the trany coolers that come with fans were too thick. I ended up using the biggest B&M I could find and it hasn't failed me yet. I am sure you will do even better having the fan when needed.

 

I saw the coolers with the fan already but they were the old-school tube and fin style which is prone to damage, not as efficent and about 3/4" thicker than the B&M cooler/ Spal combo.
When I get the chance I think I will also add one of those fancy fan thermostat switches so it turns on automatically as needed but still retaining the manual switch just in case.

When i do that I can also paint the brackets black and heck once the grille is off again (which is difficult with a winch) I may do the "Grille Mod" and/ or add Northridge's IPF headlight conversion.

 

Did you install a thermostat switch yet?

 

I never did install that. I got into such a habit of turning on the fan in stop and go traffic and on the trail that it is just second nature for me just like turning on the headlights when it is dark. Funny though when I drive my wife's Saturn Vue I find my-self reaching for the switch in traffic.

 

This is a really good up grade and a needed one when your on the trail and moving slow even with the cooler my trans reaches over 200 deg. Great detailed write-up BTW, Thanks.

 

This is nice, my next mod for sure. Where did you get the Spal fan ? and how much ?

Thx

 

this is going to be my next project thanks for all the info and photos.

 

I got mine off Ebay with the shipping it was $61 dollars.

 

Like the cooler/fan combo but is there a temp gauge for this also?