will this work for transmission temp?

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letank
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Re: will this work for transmission temp?

Post by letank »

Grand_Wag_85 wrote::shock: Slight hijack...on the TF727 which of the cooler lines is the outbound line and which is the inbound?

Also, they say to put the probe in the hottest part of the trans. Would that be the pan or the outbound pressure line?
the return line from the cooler is the one in the back of the TF727, so the front line at the trany is the output to the cooler.

I did not want to deal with extra fittings on the cooler lines, So I used one of the service ports, as pictured earlier on page 1 post #2. Waiting for summer to see real temp readings.
Michel
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Grand_Wag_85
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Re: will this work for transmission temp?

Post by Grand_Wag_85 »

I saw the post where you referenced the service port. I'm putting in a cooler and was feeling too lazy to start a new post :p
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will e
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Re: will this work for transmission temp?

Post by will e »

I figured even if i didn't have 'the hotest' place in the transmission I would know what 'normal' is for the location. Good enough for me.

I do think i read somewhere that the service port was used on some cars and trucks that had factory transmission temp gauges.
81 Waggy 'WILL E' Retired
82 Cherokee WT - SOA/SF/high steer/Alcan springs/agr box/Borgeson steering shaft/AMC 401/performer/holley TA/HEI/BeCool/727/ALTAS (2.0/2.72/5.44)/D60 Snofighter(Yukon Zip,hubs,stubs,4.56)/14 Bolt (FF,BF shave, Discs, ARB,Artec Truss)/MTR 37X12.5/Corbeau XRS Baja & 5 point retractable harness/Hella Aux lights/tuffy console/killer32 sliders/Evil Twin bumpers, rack and roll cage/WARN 8000/TT Fabworks steering brace/dual batts/custom TC skid plate/ARB fridge

letank
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Re: will this work for transmission temp?

Post by letank »

A little follow up. Took a long drive and we have this summer weather in the 70-74 last week.
Temp measured at the rear servo area, which is probably the coolest because it is the closest to the cooler return line:

at 65mph it stayed in the 160-165, in town with stop and go 170-173, back on secondary road at posted 55mph, it dropped to 155-158.

on the 2 to 3 mile hill climb, it went to 178-180, on the downhill, it took a while a good 2 miles to return to 170, in fact the trans fluid temp went down after the radiator temp went down -all on D mode-

the last stretch is a steep hill climb that is done in 2 gear , usually 25-30mph because of the sharp turns for 2 miles. There was a lot less increase in the temp of the transmission temp that I expected, it did not shoot over 170, the radiator temp did not go past middle, in fact it was getting colder because of the 2300' level, but it was still in the 60's. In the summer days 80's the radiator goes past the half mark for a long time as it is crawl mode for the next mile, but during this test the coolant temp did not go past the mid level, even as the gate was fubar and I had to let it idle in gear for 5 mins, back up turn around and use the other gate.

Edit: the half mark (or about) is now my normal operating coolant temp, after the CVR swap to the LM3506, the coolant temp jumped from the normal 1/3 to the half mark.

second edit: driving back at night it was 20 degrees cooler at 50ish and the trany fluid temp dropped by about 20 to 30 to 135-140F but speed of 55 or 65 did not increase trany fluid temp. The only increase to 160F was in stop and go traffic in the city from stop light to stop light
Last edited by letank on Wed Feb 14, 2018 10:55 pm, edited 2 times in total.
Michel
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tgreese
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Re: will this work for transmission temp?

Post by tgreese »

:P Just reading this after it's all done ...

Seems to me this would be a perfect application for soldering. Get a brass bushing the right size for the sender, use a step drill to make a hole in the side of the pan, thread in the bushing and use your plumbing setup to solder it in. A propane torch would be enough; brush on some flux and use plumbing solder. Easy.

But it's already done - maybe this will help someone in the future.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
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letank
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Re: will this work for transmission temp?

Post by letank »

at over 2660 views, this is the place to post, fiddling with transmission cooling line on the other project and found this post about trans temp (still running in the 160 and 170ish when going on long up hill with outside temp in the high 70's)

http://www.ifsja.org/forums/vb/showthread.php?t=134261

or

Here is a quote from the Orange ($8.95) GM manual:
--------------------------------------------------------------------------------------

"OIL TEMPERATURE MEASURED AT CONVERTER OUTLET TO COOLER.

300F is the maximum temperature. (Workhorse says 350F). This is the normal place to install a temperature gauge or signal. The temperature in this location will vary significantly with each vehicle start-up or hill. If the temperature reaches 300F (350F), reduce throttle. To lower the transmission temperature with the transmission in NEUTRAL, run the engine at 1,200 RPM for 2-3 minutes to cool the oil. Do not allow the converter outlet temperature to exceed 300F (350F).
Keep a close check to prevent the engine cooling system from overheating.

300F would be typical of rocking the vehicle in mud, snow, or sand, or a transmission in stall (full throttle, no vehicle movement). When the transmission is in stall, the transmission will develop heat at a rate of one degree per second of stall.

OIL TEMPERATURES MEASURED IN THE SUMP

150F -- Minimum operating temperature for continuous operation. It is possible in low ambient temperature to overcool the transmission with oil to air-type coolers; it is hard to overcool if used in conjunction with oil to water coolers installed in most standard automotive

190F-200F -- Maximum oil level checking temperature. Beyond this, readings are not reliable because of expansion.

285F -- Maximum sump/oil pan temperatures for short duration such as a long hill climb.

300F -- Metal parts inside the transmission begin to warp and distort in varying degrees, seals melt rapidly, and transmission fluid life is extremely short due to oxidation and distress.

AUTOMATIC TRANSMISSION FLUID OXIDATION Automatic transmission fluid
can provide up to 100,000 miles of service before oxidation occurs under normal operating temperatures of about 170F. Above normal operating temperatures, the oxidation rate doubles (useful life of the fluid is cut in half) with each 20 degree increase in temperature. The approximate life expectancy at various temperatures is a follows:
Degrees F Miles
175 100,000
195 50,000
212 25,000
235 12,000
255 6,000
275 3,000
295 1,500
315 750
335 325
375 80
390 40
415 Less than 30 minutes

After-market temp gauge should be installed in the lower (hot) line entering the lower fitting of the radiator.

After-market external oil to air cooler should be installed in series. The hot oil line should go first through the aftermarket cooler then into the radiator to maintain proper minimum temp of the trans in low ambient temps.”

End of GM copy from orange manual.
Michel
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letank
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Re: will this work for transmission temp?

Post by letank »

Took a ride on a new GC trail hawk with all the bells and whistles. We did a serious hill climb on a sierras dirt trail, 4 low on a 2mile loose dirt, not exceeding 10mph. All the temp gauges you can imagine on the center dash display. Engine had been off for 45min before the trip back. The trans temp went up really fast after the first 1/4 mile we were at 194F, coolant at 195F, oil temp 213F, you have to love digital gauges. Trans temp climbed past 205F at the end of the up hill, and went back to 200F while on a level ground, outside temp was a low 80's
When I am back on both legs, time to take the waggy on the same road and see if I can make it up... for trans temp evaluation as well as coolant temp...
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Michel
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rocklaurence
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Re: will this work for transmission temp?

Post by rocklaurence »

I've run several Trans gauges, bypassed the Radiator and used a Large Aux cooler. I've noticed on new and older transmissions that they run between 160-180 during normal street driving. Off Road they will creep up to +- 200. If the temp runs any higher under extreme driving, an additional fan is need or a larger cooler is needed. I live in Florida and dont have to worry about extreme cold and temp not getting warm enough during winter. I've never agreed with introducing engine heat into the transmission via the radiator.

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will e
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Re: will this work for transmission temp?

Post by will e »

My transmission lines go through the radiator. I can pretty much use my trans temp as a engine temp gauge. The two move pretty close to each other. It will be interesting to see the difference when I bypass the transmission and use an aux cooler.
81 Waggy 'WILL E' Retired
82 Cherokee WT - SOA/SF/high steer/Alcan springs/agr box/Borgeson steering shaft/AMC 401/performer/holley TA/HEI/BeCool/727/ALTAS (2.0/2.72/5.44)/D60 Snofighter(Yukon Zip,hubs,stubs,4.56)/14 Bolt (FF,BF shave, Discs, ARB,Artec Truss)/MTR 37X12.5/Corbeau XRS Baja & 5 point retractable harness/Hella Aux lights/tuffy console/killer32 sliders/Evil Twin bumpers, rack and roll cage/WARN 8000/TT Fabworks steering brace/dual batts/custom TC skid plate/ARB fridge

letank
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Re: will this work for transmission temp?

Post by letank »

letank wrote: Thu Nov 17, 2016 10:25 am
Yes, it does both, from Maxtow, double vision $70
check the website, they have all the adapters you can imagine for any option
maxtow.com

Image
5000 miles later and a few years (8 years), the gauge started to fail, readings were bouncing all over... on a longer ride, the gauge maxed to 260, both analog and digital... sometimes returning to normal value of 160 to 180 depending on speed and hill climb!

Not too sure if it is voltage related as in thermal failure of some components, as it stays accurate for trips less than 30mins. After refilling with gas... well I do half refill to avoid sticker shock... so I refilled a few times on long trips, the gauge seems to be happy!
Michel
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Yeller
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Re: will this work for transmission temp?

Post by Yeller »

In my opinion most aftermarket gauges are crap at best, there are a few exceptions, but the big name racing gauge companies all suck. Voltmeter for instance on one of my trucks, starts out at 14.5 volts, after an hour is at 12 volts. Check with my mulimeter, 14.0 all the time. Same vehicle the water temp falls off as the hours progress comparing to my infrared thermometer. for what the things cost they should be awesome, but they are not. They aren't really any better than the 2 in my 52 year old FSJ.
The bus I ride is so short it is a yellow Smart Car full of squirrels, monkeys and clowns.

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https://www.fsjnetwork.com/forum/viewt ... 12&t=21395

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will e
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Re: will this work for transmission temp?

Post by will e »

I run Autometer aftermarket and am a bit disappointed in their non-stepper motor gauges. I have a vacuum gauge of theirs that read 8inches off when I installed it. (It had sat on the shelf for a few years so I couldn't return it) so I repurposed it. Their volt meter isn't accurate either. I don't know if the oil/trans temps are accurate, but they are consistent, the oil temp seems to read a bit hot in my humble opinion.

The fuel pressure and oil pressure (stepper motors) are accurate. I assume my AFR meter is also accurate.

I do like having the trans temp gauge, especially wheeling.
81 Waggy 'WILL E' Retired
82 Cherokee WT - SOA/SF/high steer/Alcan springs/agr box/Borgeson steering shaft/AMC 401/performer/holley TA/HEI/BeCool/727/ALTAS (2.0/2.72/5.44)/D60 Snofighter(Yukon Zip,hubs,stubs,4.56)/14 Bolt (FF,BF shave, Discs, ARB,Artec Truss)/MTR 37X12.5/Corbeau XRS Baja & 5 point retractable harness/Hella Aux lights/tuffy console/killer32 sliders/Evil Twin bumpers, rack and roll cage/WARN 8000/TT Fabworks steering brace/dual batts/custom TC skid plate/ARB fridge
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Re: will this work for transmission temp?

Post by Yeller »

I'm a bit of an oddball, water temp, just so I know before it blows steam its hot, speedo, and a gas gauge, I'm good. Big Glowing idiot light for oil pressure, not going to watch a gauge close enough to catch any catastrophic issues anyway, and if the lifters a quiet life is good LOL. Any doubts about volts and the multimeter is coming out so who cares. If I really want to monitor stuff, mine are all OBDII, I have a wifi dongle and an ap on my phone, I can monitor and log any parameter I want except oil pressure, only because it doesn't monitor that and I have the oil pressure switch turned off in the ECM so it will start and run without that input. Sucks out wheeling, loose oil pressure when you really need the motor to run and it shuts down due to no oil pressure and slams you on your lid........
The bus I ride is so short it is a yellow Smart Car full of squirrels, monkeys and clowns.

1970 J2500 Resto Mod
https://www.fsjnetwork.com/forum/viewt ... 12&t=21395

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https://classicbroncos.com/forums/threa ... st-3411909

letank
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Re: will this work for transmission temp?

Post by letank »

Thank you for the feedback.

Next step will be to connect an DVM and see what happens.

Same with the gas gauge... I need to do the same test, gauge is new... well newer... 5 or 6 years old, never really worked, even after sending a ground from the dashboard!

I am the ECU, so I monitor as much as I can, albeit the hearing is not top... so hard to pick up pinging... time to install a knock sensor!
Michel
74 wag (349 Kmiles... parked, next step is a rust free body)
85 Gwag (229 Kmiles... the running test lab)

letank
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Re: will this work for transmission temp?

Post by letank »

BTT, on the return trip the gauge behaved as should be... what is the difference :time of driving on first start.... on the outbound trip I had been driving for about 2hrs when the gauge started to act weird while on the inbound trip I stopped after 50 miles (or 1hr) for refueling... the alternator had been charging as much as in the 15v range (as accurate as the aftermarket gauges are) but upon restart the gauge indicated a lower voltage, above 14v....

So my theory is that the alternator is giving too much voltage to the maxtow gauge poor specs components, and I was thinking -danger- to put some resistor to drop the voltage to the max tow gauge... of course the easy way would be to turn off the engine while driving... and restart to see what is happening... in fact I did that on the outbound trip because I had noticed that the key can be jiggled a bit and the display of the charging changes... but in that outbound trip it did not do the expected reset...

Fun with our dinosaurs...

So what type of resistor would I put on the input of the maxtow gauge... something small enough to be manageable... may be some resistor wire used for our coils!
Michel
74 wag (349 Kmiles... parked, next step is a rust free body)
85 Gwag (229 Kmiles... the running test lab)

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will e
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Re: will this work for transmission temp?

Post by will e »

I'd go with the resistor wire. That's the kind of hack that will drive the next owner absolutely insane trying to trouble shoot.
81 Waggy 'WILL E' Retired
82 Cherokee WT - SOA/SF/high steer/Alcan springs/agr box/Borgeson steering shaft/AMC 401/performer/holley TA/HEI/BeCool/727/ALTAS (2.0/2.72/5.44)/D60 Snofighter(Yukon Zip,hubs,stubs,4.56)/14 Bolt (FF,BF shave, Discs, ARB,Artec Truss)/MTR 37X12.5/Corbeau XRS Baja & 5 point retractable harness/Hella Aux lights/tuffy console/killer32 sliders/Evil Twin bumpers, rack and roll cage/WARN 8000/TT Fabworks steering brace/dual batts/custom TC skid plate/ARB fridge
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tgreese
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Re: will this work for transmission temp?

Post by tgreese »

Ya know, as I understand it, 15V is too high for your charge voltage. It should be more in the range of 13.5 volts. May not seem like much, but the battery voltage is 12.6 volts. The alternator holds the charge voltage just above the lead-acid chemical potential for 6 cells times 2.1 volts. Anything above that generates heat in the battery due to its internal resistance.

So yeah, 15 volts says bad voltage regulator to me. Not poor gauge performance.

If you wanted to hold the voltage to the gauge at 13.5 volts with a 15 volt input, there are adjustable LDO (low drop out) voltage regulator chips that will regulate to the set voltage from as low an input as the set voltage plus the barrier potential of one transistor (ca 1/2 volt). Even at the drop-out voltage, the regulator will still supply the source voltage minus the drop-out voltage. However - IMO, that's a wild goose chase. Look to the charging system if the input voltage is too high.

Take the belt off the alternator and drive. You can run on battery power for hours, as long as you don't use lights or the starter (much). See what your gauge does.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
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Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
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tgreese
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Re: will this work for transmission temp?

Post by tgreese »

There are lots of regulators to chose from-
https://www.mouser.com/c/semiconductors ... rt=pricing

Most are SMD (surface mount) type. You can buy a perf board for a SMD chip and solder it to that (not difficult). Then attach your leads. Not recommending it - just pointing out how you'd drop a few volts if you needed to.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.

letank
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Re: will this work for transmission temp?

Post by letank »

Mike and Tim, thank you.
I should have been more accurate.... the gauge is off, it reads 13v when the battery is fully charged! and I do not need to add distilled water, so the charging as good as can be. For the sake of accuracy I will connect a DVM to the battery on the next start up and at a full engine operating temperature.

So it is roughly 14.5v at freeway speed!
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tgreese
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Re: will this work for transmission temp?

Post by tgreese »

Apologies, it seems I misunderstood the issue. This is about the voltmeter reading too high?

First, I would mention that these batteries (apparently) can be pumped-up above their nominal potential by a charger. If someone has some physical insight why this happens, I'd be interested. Capacitive loading maybe? :idea: I think it's not unusual for a for a car battery fresh off the charger to measure at 13 volts. If you have a decent multimeter, suggest you compare your meter readings to what you measure at the battery. You could measure with more than one multimeter and compare readings, both on your Jeep battery and to a 1.5 and 9 volt disposable battery.

JMO - 14.5 is still pretty high. Your dash meter could be right and be pointing to the voltage regulator.

If you wanted to adjust the reading of your dash voltmeter downward, you'd use a voltage divider. Assume the input impedance of gauge is rather high. Connect a 1000 and 9000 ohm resistor in series, between the "12V" supply and ground. 10K ohms would sink 1.2 mA, not a lot, about 0.0256 watts. You connect the gauge to the junction between the two resistors, to reduce the input voltage by 10%.

Note that the gauge is now in parallel with the 9K resistor, and its current drain should not change the voltage perceptibly at that point if its input impedance is sufficiently high. If the meter loads down the divider, you could add an op amp at unity gain between the junction and the meter. The op amp has a very high input impedance, and at unity gain would mirror the voltage at the junction, driving the gauge.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.
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