04 KJ Trans and towing question

Geof3

Member
Joined
Apr 12, 2016
Messages
74
Reaction score
0
Location
Colorado
Hey all, been awhile since posting, the 3.7 KJ is doing well. My wife and I are purchasing a small 2900’- 19’ long (Cherokee Wolf Pup 14cc) trailer and I’m trying to figure out if i have the “aux” trans oil cooler. My trans only has about 20k on it as it was a new install a couple of years ago. I don’t have the official tow package, but I am adding the HD fan setup with the mopar parts. He Jeep already has OME shocks and springs as recommended by Tom, and running 275/45 16 tires. Its seems I’ll be good to go overall, but with Colorado mountains and what not, I want to be sure I don’t cook my trans. I’ve got the small narrow cooler that sits in front of the radiator and the AC, so it basically looks like I have 3 radiators. Is this small, forward cooler the aux cooler, or is there something I’m missing? I searched and didn‘t find anything definitive? Any tips/tricks would be appreciated!
 

klc

“It flies like a truck.”
KJ Supporting Member
Joined
Jan 14, 2022
Messages
305
Reaction score
398
Location
PNW
That might be a transmission cooler, but if it doesn’t have the engine-mounted fan the Jeep doesn’t have the Tow package. The transmission lines connect to the lower right corner of the cooler, you can see them if you look straight down behind the main on that side.

You can enter your VIN and get your build sheet here:

 

tommudd

Moderator
Staff member
Moderator
Joined
Jul 14, 2005
Messages
21,986
Reaction score
3,140
Location
Southeastern Ohio
Hey all, been awhile since posting, the 3.7 KJ is doing well. My wife and I are purchasing a small 2900’- 19’ long (Cherokee Wolf Pup 14cc) trailer and I’m trying to figure out if i have the “aux” trans oil cooler. My trans only has about 20k on it as it was a new install a couple of years ago. I don’t have the official tow package, but I am adding the HD fan setup with the mopar parts. He Jeep already has OME shocks and springs as recommended by Tom, and running 275/45 16 tires. Its seems I’ll be good to go overall, but with Colorado mountains and what not, I want to be sure I don’t cook my trans. I’ve got the small narrow cooler that sits in front of the radiator and the AC, so it basically looks like I have 3 radiators. Is this small, forward cooler the aux cooler, or is there something I’m missing? I searched and didn‘t find anything definitive? Any tips/tricks would be appreciated!
A regear would sure be nice, if not, its going to be a little tough on the transmission , running hotter etc
 

LibertyTC

Well-Known Member
Staff member
Moderator
Joined
Oct 24, 2008
Messages
8,708
Reaction score
1,294
Location
B.C. Canada
Having the heavy duty cooling (viscous fan clutch and shroud) is very good to a cooler running KJ.
There is a small power steering cooler up front as well.

The OEM stamped steel transmission pan remains real hot & I replaced mine long time ago with a PML 42RLE machined aluminum transmission pan.
The PML transmission pan stays much cooler, and provides about 1.25 quarts more fluid than stock. Mine is installed with 42RLE Lubelocker gasket. (no leaks ever)

I pull a boat at 4000 lb in summer in the mountains, and Jeep likes the new PML, what a difference !
If you ever get an (overheat) TRANS-TEMP dash warning light, (refer to owners manual) & the ATF+4 fluid & filter needs to be changed ASAP.
Ever since installing the PML pan never a warning light again. PML is 1.25 quarts over capacity & has a drain plug. PML pan is capable of mounting a temp sensor as well.
 

Attachments

  • Steering Fluid Cooler.jpg
    Steering Fluid Cooler.jpg
    99.4 KB · Views: 16
  • PML Pan and LL Gasket.jpg
    PML Pan and LL Gasket.jpg
    444.4 KB · Views: 17

Geof3

Member
Joined
Apr 12, 2016
Messages
74
Reaction score
0
Location
Colorado
Here is a pic of the cooler I mentioned. It appears the lines do go back to the trans… I like the idea of the PML pan, that’s an easy one. I read in another thread about a scanner (Scangauge) that seems to monitor temps and multiple other items, that would be a good addition. I’m due for new tires as well and the Toyo’s I’m buying are nearly 10lbs lighter a piece over the Wranglers I currently have, which should help.
 

Attachments

  • 8108E947-DC4B-4C96-B9CA-0425A2FA3B15.jpeg
    8108E947-DC4B-4C96-B9CA-0425A2FA3B15.jpeg
    233 KB · Views: 14
  • 7EFDB99A-8A12-4106-A323-1F9C63AF8BAE.jpeg
    7EFDB99A-8A12-4106-A323-1F9C63AF8BAE.jpeg
    313.5 KB · Views: 14

JeepJeepster

Full Access Member
Joined
Dec 15, 2004
Messages
8,847
Reaction score
238
Location
Dem hollers in Ky
I too have installed the PML pan and it does keep the trans a good bit cooler (I have a trans temp gauge). Plus, it seemed like the stock stamped pan was always leaking, I even bought a new dorman pan and torque to the FSM specs, still seeped fluid. the PML pan is nice and dry.

That is the factory AUX trans cooler but Ive recently learned that the KJ may have come with a bigger trans cooler if the KJ had the towing or offroad package. Im going to try to order one to see if it fits.
 

klc

“It flies like a truck.”
KJ Supporting Member
Joined
Jan 14, 2022
Messages
305
Reaction score
398
Location
PNW
I too have installed the PML pan and it does keep the trans a good bit cooler (I have a trans temp gauge). Plus, it seemed like the stock stamped pan was always leaking, I even bought a new dorman pan and torque to the FSM specs, still seeped fluid. the PML pan is nice and dry.

That is the factory AUX trans cooler but Ive recently learned that the KJ may have come with a bigger trans cooler if the KJ had the towing or offroad package. Im going to try to order one to see if it fits.
Do you think this pan will work with a skid plate?
 

klc

“It flies like a truck.”
KJ Supporting Member
Joined
Jan 14, 2022
Messages
305
Reaction score
398
Location
PNW
Looks pretty much the same as mine.
You must be registered for see images attach
 

Geof3

Member
Joined
Apr 12, 2016
Messages
74
Reaction score
0
Location
Colorado
Well gang, thanks for all the help! But after careful consideration I decided to buy a Porsche Cayenne for towing duties! It’s rated at nearly 8k lbs towing capacity. Should haul this little trailer with no issue!
 

runfor5

Member
Joined
Dec 29, 2019
Messages
52
Reaction score
33
Haha this was a very unexpected ending to the original question. Congrats on the P-car [SUV] purchase!
 

Latest posts

Members online

No members online now.
Top