42RLE getting hot

i stuck a 16" heat sink tube right up front on the V brace was this a bad idea?

not really meant to be a forever piece....... just until the ass end is finished and i can find a permanent home underneath for a powered unit.
No, I did the same thing on my previous TJ. At least so long as you plumbed it into the output of the factory cooler in the radiator. By itself it would not be enough cooler. In front of the factory cooler it won't help cool the transmission at all.
 
Do you have a temperature sensor? The factory transmission temp is not available just by plugging in some computer. You are probably watching coolant temp. The trail dash ain't a drb.
Im not looking at coolant temp, it says transmission fluid temperature. The one in the middle is the engine coolant temp and the one to the left is transmission fluid temp
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Im not looking at coolant temp, it says transmission fluid temperature. The one in the middle is the engine coolant temp and the one to the left is transmission fluid temp
There is no transmission temp available on a 42rle unless you put a sensor in the pan. I don't know how they make at number but it probably isn't your transmission temperature, that's why it seems hot.
 
No, I did the same thing on my previous TJ. At least so long as you plumbed it into the output of the factory cooler in the radiator. By itself it would not be enough cooler. In front of the factory cooler it won't help cool the transmission at all.
There is no factory transmission cooler I thought?
 
There is no transmission temp available on a 42rle unless you put a sensor in the pan. I don't know how they make at number but it probably isn't your transmission temperature, that's why it seems hot.
Before it was rebuilt the guy plugged in a code scanner and it said high temperature operation achieved, so how would it come up with that if there is no temperature sensor?
 
It's a little crud since I was just using some scrap pieces. But welded on a couple tabs + cross piece for a transmission cooler on the v-brace. Been working just fine and I don't think I've seen temps past 150ish while driving. Including this past weekend going over Hwy 20 (Wa State) with my foot to the floor the whole way up the pass.

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It's a little crud since I was just using some scrap pieces. But welded on a couple tabs + cross piece for a transmission cooler on the v-brace. Been working just fine and I don't think I've seen temps past 150ish while driving. Including this past weekend going over Hwy 20 (Wa State) with my foot to the floor the whole way up the pass.

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Where is the temp sender? Everyone needs to know where they are installed when a given temp is listed.

In our part of the world, with a cooler at least twice as good as that one and the sender in the pan, we are seeing 210-220 when the trans is being worked hard. Our ambient is 95+F.
 
Where is the temp sender? Everyone needs to know where they are installed when a given temp is listed.

In our part of the world, with a cooler at least twice as good as that one and the sender in the pan, we are seeing 210-220 when the trans is being worked hard. Our ambient is 95+F.


Good point. My temp sensor is in the pan. Ambient temps while driving this past weekend ranged from 70-90. Edit: Low to mid 70's while going up the pass.
 
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That's exactly what I was thinking, the transmission shop claimed that they couldn't fit the cooler in the front because of some bars which I believe are supports for the radiator which they said is aftermarket and I think it is to because the cap says Champion

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I mounted my cooler on the V bar. Temp sender is in the pan. Gauge on the console behind the shifter.

https://wranglertjforum.com/threads...4-supercooler-in-your-jeep-wrangler-tj.15329/
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so i found something i'm not sure i'm happy about.

the cooler seems to be functioning fine.
BUT.
when i shut the engine down all fluids return to the lowest points they can reach. this allows 1/2 the trans oil to gravity drain out of the cooler and back down into the trans.
so in theory the trans is as if it's way overfilled until the extra volume the cooler holds is pumped back into it and it is once again full.
parked/cold, the dipstick level shows it way overfilled. it's takes a few minutes for the trans to pump the cooler full then the stick reads just over 1/2 way between the add and full dimples on the stick.
i need to get it hot again and get that level right when the sys is functioning and the cooler is full, which means adding just a bit more oil.

how hard is pushing all this extra fluid gonna be on the trans itself? does this need addressed or corrected?

i wish i could get the cooler lower it the sys, this would limit drain back, but it's this or nothing for now.
 
so i found something i'm not sure i'm happy about.

the cooler seems to be functioning fine.
BUT.
when i shut the engine down all fluids return to the lowest points they can reach. this allows 1/2 the trans oil to gravity drain out of the cooler and back down into the trans.
so in theory the trans is as if it's way overfilled until the extra volume the cooler holds is pumped back into it and it is once again full.
parked/cold, the dipstick level shows it way overfilled. it's takes a few minutes for the trans to pump the cooler full then the stick reads just over 1/2 way between the add and full dimples on the stick.
i need to get it hot again and get that level right when the sys is functioning and the cooler is full, which means adding just a bit more oil.

how hard is pushing all this extra fluid gonna be on the trans itself? does this need addressed or corrected?

i wish i could get the cooler lower it the sys, this would limit drain back, but it's this or nothing for now.

you dont check an automatic transmission while the engine is off.

you’re worrying about something that is not a problem.
 
so i found something i'm not sure i'm happy about.

the cooler seems to be functioning fine.
BUT.
when i shut the engine down all fluids return to the lowest points they can reach. this allows 1/2 the trans oil to gravity drain out of the cooler and back down into the trans.
so in theory the trans is as if it's way overfilled until the extra volume the cooler holds is pumped back into it and it is once again full.
parked/cold, the dipstick level shows it way overfilled. it's takes a few minutes for the trans to pump the cooler full then the stick reads just over 1/2 way between the add and full dimples on the stick.
i need to get it hot again and get that level right when the sys is functioning and the cooler is full, which means adding just a bit more oil.

how hard is pushing all this extra fluid gonna be on the trans itself? does this need addressed or corrected?

i wish i could get the cooler lower it the sys, this would limit drain back, but it's this or nothing for now.
How do it know it is pushing extra fluid?
 
The transmission pump deals with clutches that require 110 to 145 psi to operate. You are talking about blowing some fluid through an essentially open line. This is absolutely nothing to worry about.

the cooler seems to be functioning fine.
Perfect, get the fluid level right and then add an extra quart for good luck.
 
How do it know it is pushing extra fluid?
when running and up to temp it's right at the full line (now).
seems like 1/2 the cooler capacity or whats level with the entrance and exit holes can drain back down toward the pan and cause what would seem like an over filled situation in the trans until it fills that cooler up again.