JeepMateo

I do have an obd2 reader that I have been using to get live data temp readings, not only relying on the gauge.

Mr.T

Yep, I know -- But that's just a another readout of the same ECT sensor reading as the dash.

Measuring the temperature with something else and comparing isn't easy. Typically there are two choices, a contact type thermometer and an infrared type (least accurate). Neither is measuring the coolant itself, so something like the thermostat housing surface temperature is measured -- Which will be a slightly cooler than the coolant itself.

JeepMateo

okay, thanks. any other Ideas?

resharp001

I just went back and read your original post. I would say that my jeep is fairly comparable in some respect. I have 3.6L auto, 37s, 4.88 gears, and my grill is decently blocked by bumper bar, light, winch, etc. The one difference we probably have is I replaced my factory rad a couple years ago with an OSC unit. I'm not as heavy as your jeep, and I don't have steep inclines, but I deal with extreme heat. Just my opinion, but based on what you're saying, I don't think it's really an issue with your jeep, but more something you have to work around. I have been watching my temps closely the last few weeks as temps here in Texas have started creeping up to our normal summer temps. In a 30 minute drive on the interstate to get home, with ambient temps ~97*-100*, and RPMs revving in the 2800-3k range, my coolant temps have been rising up in the 230's. If I slow down and bring the RPMs down, they stay more in check. I occasionally look up and see I'm pressing towards 240* and back off quickly. Even forcing the fan to run on high from the start, I'm hitting those levels....it just takes a little longer to get there. My general experience over the last 7 years and various gearing/tire combos, has me believing that the 3.6L just isn't that forgiving when it comes to higher RPMs, both in regard to fuel economy and coolant temps. I can totally see how climbing grades with weight, probably in 3rd gear and revving 4500+ RPMs is making those coolant temps shoot up there. I'd bet mine would do the same if I was revving that high. Anyhow, I don't think it's so much an issue (although could be wrong of course), but rather just the way it is. I'm to the point that I'd pony up for a larger aluminum rad as I think increased capacity is the only real solution left, but the reliability of those rads sure hasn't improved over the years, or at least that is how it seems to me.

JeepMateo

This is very helpful, thank you! Gives a lot of peace knowing that I’m not the only one who is having this happen.
I just checked out the flex a lite radiator upgrade and I think that might be my help. This is what I was looking at but can’t seem to find it for sale anywhere...
https://www.fourwheeler.com/how-to/e...-your-jk-cool/

resharp001

Just to be totally clear, those are just my feelings based on my experience. I had 5.13 gears with 37s previously and ran into this a bit the last couple years, but this year seems to be a little more prevalent. Maybe I'm just watching them closer as we heat up since I swapped front bumpers this last year and now my winch sits higher rather than being recessed. Surely the more we block the rads the less efficient we're making them, but given my little "fan on high" test I'm not sure to what extent the passive air flow is coming in to play (vs. being pulled through via the fan). I need to do more research on the current aluminum options myself in regard to reliability, and also if the additional cooling capacity really is having that much of an effect or not. Seems like I've seen some varying remarks on this in the past. I'm just at the point myself that additional capacity seems like the last logical solution for my case.

JeepMateo

totally understood.
Well I went so far as to take my hood off and Take a drive on the freeway just to see if a vented hood would help, but nope, still got hot haha! Still ended up putting the vents on, already had bought it...

resharp001

I installed a PSC cheese grater several years back. Might have lowered ambient engine bay items by a degree or two, but didn't make a hill of beans difference in engine/coolant temps. I've never been willing to put more into ventilation a la TOTL or AEV hoods. I can't imagine they make THAT big of a difference.

resharp001

I've been trying to dig up some reviews on the Flex A Lite today. Can't find much on any of the forums in the last few years. Sure is pricey, and would hope it works like a charm, but scary to feel like the guinea pig on $970 radiator. Did a swim through the AFE BladeRunner GT and Mishimoto V2 again....always leaves me feeling like there are no good options. You'd think that for that much jack you'd get fan and everything included. I'd just like to see a few people saying everything bolted up perfectly even....trans cooler and all.

Mr.T

Is there any chance the ratio of anti-freeze to water is more than 50/50 ? The more the anti-freeze the higher the maximum temperature at full load. Ethylene glycol doesn't transfer heat as well.

Redline has a product called Water Wetter, here's a link to a pdf with some technical info. I haven't used it, but it might be worth a try -- There's a table in this pdf showing an 8 degree drop by adding Water Wetter to a 50/50 mix (which is the same temperature drop as using pure water). It also shows a 26 degree drop with pure water with water wetter compared to a 50/50 mix.