External Transmission Cooler

[Logan Savage]

Just found a radiator leak on my 02 Liberty which has the trans fluid cooler built into the radiator . I have an 05 parts Liberty that I could use the radiator & external trans fluid cooler out of . The 02 has the 45 trans & the 05 has the 42 trans so I don't know if a line swap is possible . If a line swap isn't possible I need to know if I can cut the lines at the front of the engine & connect the 42 lines to the 45 lines without too much trouble . Anyone know how much pressure is in these lines ?

 

[Logan Savage]

Just went out & looked at the 02 & 05 . It's raining so I didn't examine closely but it appears as though the metal lines from the transmission transition to rubber hoses at the front of the engines with just hose clamps on them . Perhaps it will be a fairly easy swap . If anyone has made this swap I'd appreciate hearing about it .

 

[renegade 04]

You will need to buy a 2002 radiator with the in radiator transmission cooler. The in radiator transmission cooler is miles above a crappy external transmission cooler and just running a external transmission cooler will over heat the transmission fluid.

 

[HoosierJeeper]

Or you could upgrade to a larger external cooler, when the shop rebuilt my trans they did that and said it would make it hard to overheat.

 

[TwoBobsKJ]

I basically did what you're asking about - only in reverse.

I added the in-rad ****** cooler to my '03 that has the external trans cooler. As long as you're able to hang the '05s external cooler on the front of your '02 ****** you'll be just fine.

Here's what mine looks like. The arrows point to the original lines from the transmission:

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Bob

 

[tjkj2002]

Or you could upgrade to a larger external cooler, when the shop rebuilt my trans they did that and said it would make it hard to overheat.

Hard to overheat,not really but will take forever to warm up and shift correctly.

 

[HoosierJeeper]

Mine seems to warm up and shift fine this winter since the rebuild. Better than it did last winter. Been down to -23F without windchill here and it shifts fine. I don't doubt that a huge cooler would screw it up with the cold, so far I'm not seeing it with this one.

I can't remember if they said it would be hard to overheat but they said it's an upgrade. It's not massive. Better placed too so the winch doesn't block it like what it did to the stock one.

 

[Logan Savage]

My 05 doesn't have a cooler in the radiator , just the external cooler . That was the problem with installing an 05 radiator in the 02 . I went to my country property this afternoon & got the external cooler off the parts 05 . It does just have two rubber hoses on it that connect to the metal transmission lines with hose clamps .
I could have just bought a new radiator for the 02 but I already had all the parts from the 05 I have for parts . I'll probably do the swap tomorrow unless I run into unforeseen problems .

 

[Logan Savage]

I basically did what you're asking about - only in reverse.

I added the in-rad ****** cooler to my '03 that has the external trans cooler. As long as you're able to hand the '05s external cooler on the front of your '02 ****** you'll be just fine.

Here's what mine looks like. The arrows point to the original lines from the transmission:

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Bob

Did your 03 have the in radiator cooler that wasn't being used or did you buy a different radiator ? The one thing I'm wondering about is , the 02 has the 45 trans & radiator cooler & the 05 has the 42 trans with just the external cooler . Did your 03 have a 45 trans with just the external cooler before you upgraded it ?

 

[uss2defiant]

bob has a 42rle but used an 02-03 radiator with the inline cooler for better cooling.

 

[renegade 04]

I also have the two cooler set up and I love it, especially when towing at or over its rated tow limit.

 

[TwoBobsKJ]

Did your 03 have the in radiator cooler that wasn't being used or did you buy a different radiator ? The one thing I'm wondering about is , the 02 has the 45 trans & radiator cooler & the 05 has the 42 trans with just the external cooler . Did your 03 have a 45 trans with just the external cooler before you upgraded it ?

bob has a 42rle but used an 02-03 radiator with the inline cooler for better cooling.

^That^

My '03 just had the external cooler originally. The original radiator cracked on the upper neck and needed replaced so I got a rad for an '02, plumbed it as you see in the pic and now there are two coolers in series.

Between off roading and towing my boat I've tried to keep the trans temps stable. This system seems to do the trick very well - plus adding the HD cooling with the viscous fan and extended shroud supplements the electric fan.

Bob

 

[Logan Savage]

As I said before my 02 has the 45 transmission & the cooler built in the radiator . Today I installed the radiator out of an 05 with the external cooler . The 05 radiator has brackets the external cooler fits in & two bolts . Everything fit perfectly . The metal lines from the transmission ended right at the front of the engine & had rubber hoses that originally went to the radiator . The external cooler had rubber hoses that went to the metal lines on the 05 . On both models the rubber hoses slid over the metal lines & just had those clamps that you squeeze with pliers . The metal lines had barbs on the ends .

 

[Dave]

As I said before my 02 has the 45 transmission & the cooler built in the radiator . Today I installed the radiator out of an 05 with the external cooler . The 05 radiator has brackets the external cooler fits in & two bolts . Everything fit perfectly . The metal lines from the transmission ended right at the front of the engine & had rubber hoses that originally went to the radiator . The external cooler had rubber hoses that went to the metal lines on the 05 . On both models the rubber hoses slid over the metal lines & just had those clamps that you squeeze with pliers . The metal lines had barbs on the ends .

Glad it all fit and worked out good for you, Logan.


Dave

 

[JeepJeepster]

Ill have to look again but I think all of the hoses are crimped on my 04. I could be wrong though.

With the stock cooling my 42rle doesnt get above 100F in the winter. If Im in stop and go traffic it will but not at hw speeds.

It will hit 200F pretty easy in the summer. Viscous fan doesnt seem to have changed anything. Just roars a lot...

 

[tjkj2002]

Ill have to look again but I think all of the hoses are crimped on my 04. I could be wrong though.

With the stock cooling my 42rle doesnt get above 100F in the winter. If Im in stop and go traffic it will but not at hw speeds.

It will hit 200F pretty easy in the summer. Viscous fan doesnt seem to have changed anything. Just roars a lot...

My '02(45RFE) with a in-radiator cooler and AUX cooler will see 120 degrees in -10 degree weather and reach it rather quickly(20mins driving) and never has gone above 180 degrees even towing 4200lbs through the rocky mountain passes at 65mph+.

You want the temps to get above 100 degrees even at highway speeds in a auto trans otherwise the fluid will be to thick for the trans to operate correctly and efficiently.