Transmission cooler tester needed

I still think you're silly for undertaking this much effort for no benefit to yourself other than knowledge so I really appreciate it. Having done this locally with an improperly geared rig and then after regearing, what may be contributing to lower temps that we expected is the correct gearing.

I've seen lots of shops back east on FB telling everyone that 3.73 and 37's are just fine. I suspect if the owners ever installed a decent temp gauge, there would be some interesting discussions between them and the shop owners.

Maybe those "shops" are also transmission "Shops"
LG
 
I still think you're silly for undertaking this much effort for no benefit to yourself other than knowledge so I really appreciate it.
I'm happy to help.

Having done this locally with an improperly geared rig and then after regearing, what may be contributing to lower temps that we expected is the correct gearing.

I've seen lots of shops back east on FB telling everyone that 3.73 and 37's are just fine. I suspect if the owners ever installed a decent temp gauge, there would be some interesting discussions between them and the shop owners.

I'd prefer to get to 5.38 but the juice isn't worth the squeeze until I also get ARBs and am in there anyway.

I imagine way too many people shrug and say "it's a jeep thing" when they have a rig that's terrible on the street (and presumably not great on trail, but that's at least somewhat maskable in low range), simply because they don't know better.
 
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I imagine way too many people shrug and say "it's a jeep thing" when they have a rig that's terrible on the street (and presumably not great on trail, but that's at least somewhat maskable in low range), simply because they don't know better.

I know at least for me until last year it was simply because I didn't really know/didn't have the drive to fix it. I knew something wasn't right considering I couldn't touch 5th gear and I was hitting the skinny pedal/brakes a ton when on trails, but I didn't really know where to look to fix that (this was when I only read this forum because it would pop up when I searched an issue). It took me complaining a few times to friends and them telling me about regearing a few times for it to properly worm its way into my head and for me to start looking. Since then I understand the systems that all work together much better and can't understand how someone can live with an improperly geared system or at least notice that something is wrong and not start questioning it like I did.

That being said, I've also met plenty of people who purposefully choose to undergear because they see lower rpms and think that it's better for the vehicle. Typically that leads me to ask why they didn't leave it stock then if low RPM is all they are chasing. These are often the same people throwing on the tallest, cheapest lift they can find and slapping on big tires then wondering why it sucks to drive now. Can't help them all.
 
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I know at least for me until last year it was simply because I didn't really know/didn't have the drive to fix it. I knew something wasn't right considering I couldn't touch 5th gear and I was hitting the skinny pedal/brakes a ton when on trails, but I didn't really know where to look to fix that (this was when I only read this forum because it would pop up when I searched an issue). It took me complaining a few times to friends and them telling me about regearing a few times for it to properly worm its way into my head and for me to start looking. Since then I understand the systems that all work together much better and can't understand how someone can live with an improperly geared system or at least notice that something is wrong and not start questioning it like I did.

That being said, I've also met plenty of people who purposefully choose to undergear because they see lower rpms and think that it's better for the vehicle. Typically that leads me to ask why they didn't leave it stock then if low RPM is all they are chasing. These are often the same people throwing on the tallest, cheapest lift they can find and slapping on big tires then wondering why it sucks to drive now. Can't help them all.

As they say, comparison is the thief of joy. If you don't know better, it can be easy to just accept it for what it is.
 
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@mrblaine I'll toss my hat in the ring in you need any other testing done, having run the Setrab for a few years now, I'm pretty familiar with the operating range. Now is a good time to test as well, since we're in our "hot" part of the year (85-90 every day and stupid moist air).

I'm probably what you would consider undergeared though at 4:88...but with a TOTAL elevation change of ~1100 feet in the WHOLE STATE, big climbs aren't really a thing here. Yes, Yes, wind, acceleration, passing power...I get it, and when my lockers die, I'll change my gearing too...

@rasband re: inflamation in your foot. Man...I feel you. I have osteoarthritis in my right ankle from an old injury in college. When it flares, its awful. Been to a specialist and the "only" thing they can do is a replacement...when I'm 65. for the next almost 20 years, I just have to deal with it. Been trying to lose a bit of weight to help and making sure I keep my shoes in good shape / wear good insoles. Overuse will sneak up on me and then I'm down for a week, unable to really walk.
 
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I still think you're silly for undertaking this much effort for no benefit to yourself other than knowledge so I really appreciate it. Having done this locally with an improperly geared rig and then after regearing, what may be contributing to lower temps than we expected is the correct gearing.

I've seen lots of shops back east on FB telling everyone that 3.73 and 37's are just fine. I suspect if the owners ever installed a decent temp gauge, there would be some interesting discussions between them and the shop owners.

Totally agree. I'd even bet some auto owners are experiencing some engine overheating issues because of it.

I found out last year what improper gearing can do to trans temps even without a trans temp gauge...
2000 4.0L 32rh with stock Dana 30/35 3.07s on 33x10.50-15 Badak Xtremes factory rad/trans cooler setup at the time. While hurrying home (80ish mph) on a nearly pancake flat interstate after dark with 80* ambient temps, i noticed the engine coolant temp starting to climb over the 210 degree mark when it always sits slightly below it. I immediately realized by the rpm that the torque converter wasn't locking up due to throttle and load to maintain that speed. I slowed down and the engine temp came back down with the converter locked up. The super hot trans fluid going through the factory radiator/cooler was too much for the system to cool. I normally pay very close attention to my converter being locked up but was in a rush that night. If that can happen to me in the pancake flat Midwest, I can only imagine what it's doing to guys in mountainous states.
 
This week was rough but I can walk again. I had planned to get the setrab in Monday and Tuesday for a testing run but here we are.

Grille is off, getting it in now. I kind of like the rat rod look.

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Today it's 82°F. Even if the temperature change was a 1:1 reflection in the cooler's performance, it's a huge shift when compared to OEM (no auxiliary cooler).

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Side by side, I adjusted the vertical axis so ambient for both is included. I may have driven a little faster today since there was less traffic, so that spike around 0:55:00 on the OEM chart looks to have shifted to the left (~0:47:30 duration)

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Side by side, I adjusted the vertical axis so ambient for both is included. I may have driven a little faster today since there was less traffic, so that spike around 0:55:00 on the OEM chart looks to have shifted to the left (~0:47:30 duration)

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View attachment 706447

What radiator are you running? Thin or thick bars? Rubber hose needed?
 
Side by side, I adjusted the vertical axis so ambient for both is included. I may have driven a little faster today since there was less traffic, so that spike around 0:55:00 on the OEM chart looks to have shifted to the left (~0:47:30 duration)

View attachment 706446
View attachment 706447

Friday is another 90° day, I am going to try to get another drive cycle in to see what kind of affect almost 10° has on this reading. Even if we are +10-15° I am well within the safe zone, but I doubt we will see more than the resolution on my gauges.

I suppose I should share what gauge I have. I am trying my best to round to what seems like the closest 5°. The ticks math out to this for me: 100, 125, 150, 165, 180, 195, 210, 230, 250. (50°/25°, 30°/15°, 30°/15°, 40°/20° - total sweep/tick sweep). That means that the resolution is best in the 150°-210° area where ticks are 15° (so needle widths are something like 5° or so).

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YOu beat me to it...I was gonna ask about how you were measuring. Do you have an IR gun? Might be a nice data point to shoot the pan when cold and when your drive is complete, just to calibrate the gage. No reason to think its off, but if its easy to prove that its on, or has a 10 degree shift, or the scaling is goofy...etc
 
YOu beat me to it...I was gonna ask about how you were measuring. Do you have an IR gun? Might be a nice data point to shoot the pan when cold and when your drive is complete, just to calibrate the gage. No reason to think its off, but if its easy to prove that its on, or has a 10 degree shift, or the scaling is goofy...etc

Even if it's off, it should be consistently off throughout these drives at least!

If I remember I can point my IR gun at the pan on Friday. That is probably a better confirmation for the starting temp than assuming it's close to ambient. Though I'm not sure starting temp is meaningful for what we care about.
 
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Even if it's off, it should be consistently off throughout these drives at least!

If I remember I can point my IR gun at the pan on Friday. That is probably a better confirmation for the starting temp than assuming it's close to ambient. Though I'm not sure starting temp is meaningful for what we care about.

Consistent yes, but I worry about scaling. Like your data suggests, there is a pretty dramatic reduction of temperature between the factory and the setrab coolers. If the scaling is off, that change may be larger or smaller than reported (like converting to Celsius from Fahrenheit). Its probably close, but if you have the tools, taking the reading is pretty simple. Then we KNOW.
 
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Today is 91°, it performed very similarly to the earlier drive but was at a slightly more elevated baseline (which seems to make sense). It did start to very lightly rain in the last 5 minutes heading home. One notable difference in how I collected data is I wrote a quick app to connect to ODBII and record the coolant temp for me. The gauge was in that 210 bubble, but the actual coolant temperature is slightly lower than that - so there's a little more variability and precision captured there.

The oil pan was 89° at start (cold start), and 168° when I parked. The autometer gauge was bottomed out at the beginning and reading nearly right at 165° when parking.

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