Installation of Trans Oil Cooler

[bobinyelm]

I asked about this on the OEM Forum, but got no replies. Though it seems pretty tame as a "mod," maybe you guys have some ideas-

2001 XJ w/o Factory Tow Package

I will be towing a 3500 pound travel trailer.

I have two trans oil coolers (not yet installed)-
One a B&M "Super Cooler" rated to 16,000 pounds gross combined weight (size 5"X11"X1.5")
One a Derale rated to 20,500 pounds gross combined (size 11" X17")

The B&M is a stacked plate, twisted tube design, supposedly very efficient.
The Derale is a regular tube-and-fin type.

I can barely fit the 1.5" thick one between the grille and the AC condensor, but it will block fewer square inches of the radiator.

The Derale will NOT fit (through the opening w/ the grille removed) unless I remove the radiator or something, even though the listing showed it for the XJ.

Question (especially to those who tow):
While both my coolers are bigger than the very small OEM towing oil cooler (as included w/ the tow package), which one (based on experience) would YOU use?

Have you had your XJ overheat, or the AC become inefficient in hot weather while towing and using a trans cooler that is mounted in front of the radiator?

As far as installation- I live in a warm climate, so I plan to hook the aux cooler in series AFTER the heat exchanger in the radiator tank.

Is the transmission return line from the radiator heat exchanger (that I want to cut into) the TOP one on the radiator that then routes to the REAR transmission fluid line?

Another option for the B&M is mounting it on the BACKside of the front crossmember under the radiator (behind the bog oval hole, about 4" X 8", in the crossmember). Anybody hazzard a guess if there is much airflow around the factory bumper through that big hole?

Bob

 

[Jeepin Jason]

http://jeepin.com/features/trannycooler/

That's how I installed mine. I'm using a 11'' x 7.5'' x .75'' B&M SuperCooler. Bypassed the heater in the radiator so my engine coolant wasn't heating my trans fluid anymore. The return line out of the radiator should be the lower line.

I'd also highly recommend installing a temp gauge.

http://jeepin.com/features/tranny_temp_gauge/

 

[Winks00XJ]

With that much weight you will want some sort of trailer brake controller. I would if I was you.

 

[bobinyelm]

http://jeepin.com/features/trannycooler/

That's how I installed mine. I'm using a 11'' x 7.5'' x .75'' B&M SuperCooler. Bypassed the heater in the radiator so my engine coolant wasn't heating my trans fluid anymore. The return line out of the radiator should be the lower line.

I'd also highly recommend installing a temp gauge.

http://jeepin.com/features/tranny_temp_gauge/

Check your installation (though if you disconnected your OEM cooler it probably doesn't matter). On mine, the TOP radiator mounted trans line connects to the REAR transmission line, which I understand is the fluid return port to the transmission.

Someone said that some Jeep manuals show the BOTTOM radiator line connecting to the REAR transmission fitting, but that theirs (later models) are plumbed like mine.

What kind of temperatures do you run w/o the radiator cooler, and while towing or wheeling in hot weather?

Bob
BTW, I just looked at the gauge install link and it confirms that the REAR transmission fitting is the return line (since it says the front one is the supply line). As I mentioned, my rear line goes to the top of my radiator.

Here's the text from the gauge install article below. Evidently some vehicles are plumbed differently for sure:
FROM: http://jeepin.com/features/tranny_temp_gauge/

"So with that in mind it's time to figure out which line is which. The supply line runs from the front of the transmission to the top of the radiator. Depending on where you decide to place the sensor, it may be easier to trace the line forward from the tranny, or backward from the radiator. "

 

[bobinyelm]

With that much weight you will want some sort of trailer brake controller. I would if I was you.

Yep, brake controller is an absolute MUST. I am hoping to get one of the new Jordan brake controllers (the old ones were discontinued in preparation for the new ones). Jordan uses a cable attached to the brake pedal to determine how much current is fed to the electric trailer brakes.

If they don't have that ready, I will probably use a Prodigy electronic proportional controller. Most folks say it's the best of that type.

Also fitting a weigh distrubting hitch and anti-sway bar.

Bob