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!
04 KJ Trans and towing question
- Thread starter Geof3
- Start date
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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:
fcacommunity.force.com
You can enter your VIN and get your build sheet here:
FCA RAM
A regear would sure be nice, if not, its going to be a little tough on the transmission , running hotter etc
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.
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.
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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.
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JeepJeepster
Full Access Member
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.
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?
JeepJeepster
Full Access Member
Yes, it does.
Related question. Has anyone towed a car on a trailer with a Liberty KJ, specifically a CRD? I have a one way trip to make and looking into utilizing my Liberty with a U-Haul car trailer, NOT a tow dolly.
Thanks.
Thanks.
sleazy rider
Retired moto tech and gearhead
Way too much weight, probably more than the tow vehicle and you’ll truly regret the experience.
if the KJ didn't come with a factory tow package, it may or may not have come with a factory installed transmission cooler. Check by looking in the grill at the radiator to see if one mounted on the lower part of the radiator, check the previous post (kic) for pictures, it will show you what to look for, if it does have one it may be smaller than the tow package one. If does not, do not tow anything of a significant weight, owners manual may give you needed info about MAX tow rating as your vehicle equipped.
i've done it.
You must be registered for see images attach
multiple times in fact.
not a diesel though.
So far, no regrets doing it.
sleazy rider
Retired moto tech and gearhead
There’s a pic for Ralph Nader’s book Unsafe at Any Speed. 
Seriously, towing more weight than your tow vehicle weighs is downright dangerous.
Seriously, towing more weight than your tow vehicle weighs is downright dangerous.There’s a pic for Ralph Nader’s book Unsafe at Any Speed.
That depends on if the trailer used has brakes. It's not uncommon to see vehicles that are rated to tow up to 1.5x their (unladen) weight when the attached trailer is equipped with brakes. It's always safer to keep the weight to the lowest amount possible and distribute it evenly.
On the topic of weight distribution, here's a really helpful demonstration on how loading affects trailer sway:
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... waiting for every semi on the open roads to crash all at once. oh wait...There’s a pic for Ralph Nader’s book Unsafe at Any Speed.
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