Ideal temperature for the 4.0?

Just to pile on - our rig has electric fans behind the radiator, small hood vents and a fresh oem cooling system. 210° is where our gauge is pegged in cool weather or hot weather, idling, cruising at highway speeds and also when we went rockcrawling on an 8/10 trail for 2-3hrs of 4low, locked wheeling.

Mine stays at 210* when doing the same and I just have a radiator.
 
Mine does the same thing without electric fans or vents. 🤫

No yeah, sorry, didn’t mean to make it sound like what the previous owners did was required. That’s just how ours showed up when we bought it.

Seems like it was built with mitigating temps in mind since both our trans and engine have electric fans added.
 
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Well if Jerry is gone, somebody has to ask.

Mopar = better quality. Duralast= China sweat shop employees. How is your Duralast radiator doing? I recently bought NGK sensors. Made in USA on one, Made in China and an NGK decal on the other. The made in China one had the wrong plug-in connector. :rolleyes: 🇺🇸
 
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Mopar = better quality. Duralast= China sweat shop employees. How is your Duralast radiator doing? I recently bought NGK sensors. Made in USA on one, Made in China and an NGK decal on the other. The made in China one had the wrong plug-in connector. :rolleyes: 🇺🇸

IDK, haven't had to replace an OEM radiator yet. In general, I'm of the belief that most everything is made in the same place by the same people. The biggest variation is in which country the "made in USA" sticker is actually placed on the box. Obviously this is a generalization.

I've had nothing but success with the parts I've bought from Autozone. Either I'm extraordinarily lucky, or the failure rate of parts store components has been wildly blown out of proportion by the internet, amplified by the fact that success stories don't make for good forum fodder. Maybe both sides of the argument are true.

But really I'm just making a joke at Jerry's expense.
 
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This thread was helpful, thanks.
My 2006 TJ (4.0L) started to overheat a few weeks back. I checked the radiator and discovered the coolant was down at least a quart. Topping it off helped, but I was scratching my head. Where did the coolant go? Shortly thereafter, I started smelling it, and then the pump really started weeping.
Another thread (https://wranglertjforum.com/threads/jeep-wrangler-tj-cooling-system-overhaul-faq.3397/) recommended replacing the thermostat with the pump, so I did, but the temperature has been pegged at 210 ever since. Previously, it would hover about halfway between the tick and 210, but it also jumped around a lot, which was unnerving when it hit 210. I thought that was too hot.
Based on what I've read here, I'm guessing the prior owner installed a lower temp version. It's good to know this (210) is normal.
 
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This thread was helpful, thanks.
My 2006 TJ (4.0L) started to overheat a few weeks back. I checked the radiator and discovered the coolant was down at least a quart. Topping it off helped, but I was scratching my head. Where did the coolant go? Shortly thereafter, I started smelling it, and then the pump really started weeping.
Another thread (https://wranglertjforum.com/threads/jeep-wrangler-tj-cooling-system-overhaul-faq.3397/) recommended replacing the thermostat with the pump, so I did, but the temperature has been pegged at 210 ever since. Previously, it would hover about halfway between the tick and 210, but it also jumped around a lot, which was unnerving when it hit 210. I thought that was too hot.
Based on what I've read here, I'm guessing the prior owner installed a lower temp version. It's good to know this (210) is normal.

195 Thermostat. 210 normal operating temperature. 👍🏼
 
X2 on the aux cooler. I run a Hayden 676 post radiator. Makes more of a diff8than i anticipated.

X2 on the OBD dongle. I got the one Mac suggested. The gauge on the dash is heavily buffered. 210ish can be anything from 197 to 230.

X2 on staying with OEM specs on the cooling system.
 
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