Jeep Wrangler TJ Cooling System Overhaul FAQ

Sed_7 said:
Hi All,
Just double checking here. Thanks @Chris for putting this together. In the parts list in the original post, it says that the radiator for for my 2000 auto 4L is 55037653AB. But on the wermopar site it says it isn't compatible. Can someone confirm fitment? Thanks!

View attachment 400642

View attachment 400644
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It will fit. The only difference with the radiators over the years that I know of is that the automatics have the cooler at the bottom for the transmission lines. Other than that though you can fit an automatic radiator in a manual, but you can't put a manual radiator in an automatic unless you were to mount an external cooler.
 
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Chris said:
It will fit. The only difference with the radiators over the years that I know of is that the automatics have the cooler at the bottom for the transmission lines. Other than that though you can fit an automatic radiator in a manual, but you can't put a manual radiator in an automatic unless you were to mount an external cooler.
Click to expand...

Thanks for the clarification! Ordering one now.
 
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'99 TJ Sport, 4.0 Auto with 135,000 miles. Runs like a top.

I had a small static leak of radiator coolant recently. Due to that, I've gone down the rabbit hole and read this entire thread and plenty of others. Thank you to all who contributed to this information. I also contacted the two prior owners - got great documentation when I bought the Jeep - and they hadn't done any swapping of cooling system parts.

I found I have a https://www.rockauto.com/en/moreinfo.php?pk=11981921&jsn=723 KoyoRad aftermarket radiator in it. This happened prior to 2015 based on what I learned from the PO's.

The leak appears to be coming from near the upper rad hose where it mounts to the radiator. I drove it 50ish miles, mixed use, and it sat for 5 days. Saw a wet spot on day 5 - not prior - under the Jeep and investigated. It was dripping in 4 spots from the bottom of the rad and had a trail up the fins to near the hose mount. I washed everything down and idled it for 20 mins yesterday. No leaks and no leaks today. I drove it about 5 miles, then let it idle for 10 mins. No leaks.

I'll keep an eye on the suspected spot and order new upper/lower hoses in prep for a swap.

Thx again for all the great info!
 
THunter said:
'99 TJ Sport, 4.0 Auto with 135,000 miles. Runs like a top.

I had a small static leak of radiator coolant recently. Due to that, I've gone down the rabbit hole and read this entire thread and plenty of others. Thank you to all who contributed to this information. I also contacted the two prior owners - got great documentation when I bought the Jeep - and they hadn't done any swapping of cooling system parts.

I found I have a https://www.rockauto.com/en/moreinfo.php?pk=11981921&jsn=723 KoyoRad aftermarket radiator in it. This happened prior to 2015 based on what I learned from the PO's.

The leak appears to be coming from near the upper rad hose where it mounts to the radiator. I drove it 50ish miles, mixed use, and it sat for 5 days. Saw a wet spot on day 5 - not prior - under the Jeep and investigated. It was dripping in 4 spots from the bottom of the rad and had a trail up the fins to near the hose mount. I washed everything down and idled it for 20 mins yesterday. No leaks and no leaks today. I drove it about 5 miles, then let it idle for 10 mins. No leaks.

I'll keep an eye on the suspected spot and order new upper/lower hoses in prep for a swap.

Thx again for all the great info!
Click to expand...

What type hose clamps are installed, hopefully the oem constant tension clamps are still there and not the worm drive clamps.
 
It is clear that the mopar radiator is the way to go however everywhere I look its not available. So the question is what is the next best option? Thanks in advance!
 
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illest83 said:
I just bought one last week from wermopar. It was for an automatic, but it will work for manual too.

https://www.wermopar.com/oem-parts/mopar-engine-cooling-radiator-55037653ab?c=Zz1jb29saW5nJnM9cmFkaWF0b3ItYW5kLXJlbGF0ZWQtcGFydHMmbD00Jm49QXNzZW1ibGllcyBQYWdlJmE9amVlcCZvPXdyYW5nbGVyJnk9MjAwMyZ0PXNwb3J0JmU9NC0wbC1sNi1nYXM=
Click to expand...

Thanks for that! Last time I had checked they were out of stock and so I ended up buying a Denso which several have said is a good alternative. Thanks again!
 
I just did an unintended complete overhaul of my cooling system and am having an interference with the upper radiator hose and the A/C pulley. I have tried twisting the ends to raise the hose out of the way and I also used a bungie chord to pull it out of the way for a while and it seemed to reform for a while, but those did not do the trick. I checked on it today after my first commute on the new system and now have a nice divot in the side where the pulley has self clearance'd the hose.

Is there a way to reform the hose? I plan on ordering a new one because the ground down portion has gone slightly past the white chords within the hose. For the new hose I would like to resolve this issue. Should I not get a Mopar replacement? Because I have seen in other forums that the Mopar hose isn't formed exactly to avoid the A/c pulley.
 
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Chris said:
It will fit. The only difference with the radiators over the years that I know of is that the automatics have the cooler at the bottom for the transmission lines. Other than that though you can fit an automatic radiator in a manual, but you can't put a manual radiator in an automatic unless you were to mount an external cooler.
Click to expand...

Will PN# 55037653AB fit a 2006 4.0 w/ Manual or do I need #55037653AC? Sounds like you're saying it doesn't matter, the outlet for the auto trans cooler will just be on the top vs the bottom.

My what appears to be original radiator cracked last night only a few weeks into ownership. 17 years, just shy of 100K miles.
 
Khaki Rubicon said:
Will PN# 55037653AB fit a 2006 4.0 w/ Manual or do I need #55037653AC? Sounds like you're saying it doesn't matter, the outlet for the auto trans cooler will just be on the top vs the bottom.
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the difference is the type of connectors for the auto trans cooler lines which doesn't matter to you if you have a manual transmission

55037653AB for '01-'04
20230325_062413.jpg


55037653AC for '05-'06
20230325_062541.jpg
 
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L J said:
the difference is the type of connectors for the auto trans cooler lines which doesn't matter to you if you have a manual transmission

55037653AB for '01-'04
View attachment 410279

55037653AC for '05-'06
View attachment 410280
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Awesome, thank y'all. I am going to go ahead and order the 55037653AB since it appears to be significantly cheaper. I might even grab two of them, since the part appears to have been discontinued...
 
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Doing this on my 2004. Ive seen discussion of two different hayden fan clutches. A sd one and a hd one. Is the hd one the one i need? Rock auto doesnt list it only the sd version.
 
Very small contribution to a thread that has been extremely helpful to me: it looks like BAM still has the Mopar 55037653AC radiator in stock.

https://www.bamwholesaleparts.com/o...-cooling-radiator-mopar-55037653ac-55037653ac

Just ordered one for when I eventually go through my '01 cooling system. I'll update here if there are any stock issues with my order, but I've shopped with them several times for Toyota parts and never had any problems.
 
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Anyone know when the manual radiators (no trans cooler) were last available from Mopar? I thought I had an aftermarket radiator (it's a manual and there's no trans cooler on it) but when I removed it to replace the AC condenser, I discovered it's an actual Mopar radiator. It's working fine with no leaks but I have no idea how old it is. Not sure if it's original or not. Given the age (2005) and miles (164k), I'm guessing it has been replaced in the past at some point but unfortunately, the multiple past previous owners didn't keep good maintenance logs. Just looking for a rough estimate on how old it might be if it had been replaced. When I drained and removed it, it looks like it's in great shape inside and out so I really think it has been replaced.
 
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