Trans Temp Gauge

[SpikeSpeigel]

So I'm guessing my local Autozone isnt going to have a switch like that... I'll let you know what I find.

 

[woody]

A friend of mine brought up an interesting point... What about using a toggle switch in the middle of the connection and getting another sending unit for the tranfer case. Then you could just label the toggle switch and save some money on an all new gauge. Any ideas on this? What is the normal operating temp for the t-case? Where would you put the sending unit at on the t-case?

For the sake of simplicity, one could drill & tap the drain plug for the temp sender. As long as it doesn't protrude too far past the inner surface of the plug into the case (and get eaten by the chain), it should be fine. Plus the plug should be more durable than trying to work with the (cast Al) case and tons easier to get to.

As far as "normal" operating temps... that's a good (new!!) question. I suppose it has a lot to do with where, when, & how the vehicle is being operated. I'd think rockcrawling Johnson Valley in July will result in much hotter fluid temp than snow wheeling in Maine in January. (or maybe not?)

Just for grins, I put a post-it note on my dashboard to check the temp when I get to work Monday. (this would be after a 25 mile commute in 2WD @ 70ish ambient temp...) We have several IR laser non-contact thermometers there and they seem pretty accurate when I've checked my thermostat housing vs what the temp gauge says... I need to change the lube out anyway... so I could compare the plug surface temp to the actual fluid temp... see if there is any meaningful differential. Next time I go wheeling in Uwharrie, I'll carry one along, take a few 'plug' readings throughout the day & keep records.

 

[SpikeSpeigel]

Well... Let me know next time you're headed to uhwarrie and I might just meet you there. It'd be a nice little drive to warm everything up and see how it's working.

 

[joecool]

i have an AW4 and i'm going to use a port just in front of the pressure line to the cooler. It's a star plug with m14x1.5 threads. I ordered an adapter from autometer this morning, pn 2267 i THINK. just an insert to go from m14x1.5 to 1/8" npt.

Hope this helps

Adam

I hate to bring back a dead thread, but where exactly is this plug(Picture)? I was looking around, but I wasn't exactly sure which one you were referring to. If anybody could point me in the right direction it would help me out a lot. Thanks in advance.
Joe

 

[XpedientJ]

I hate to bring back a dead thread, but where exactly is this plug(Picture)? I was looking around, but I wasn't exactly sure which one you were referring to. If anybody could point me in the right direction it would help me out a lot. Thanks in advance.
Joe

**Another RESURRECTION of this thread:

So, that star plug is JUST a plug, and removing it will not release
anything internal? Is this a full-flow area for meaningful temp.
sampling?Yes, a photo would be great!

 

[joecool]

**Another RESURRECTION of this thread:

So, that star plug is JUST a plug, and removing it will not release
anything internal? Is this a full-flow area for meaningful temp.
sampling?Yes, a photo would be great!

I dont actually know the answer to that question. After some more reading and convincing, I eventually decided to just go ahead and cut one of the hard lines and insert a t-fitting. It turned out to be a lot easier than I thought. I used the Jeepin article as a guide (http://www.jeepin.com/features/tranny_temp_gauge/) Just take your time and plan it out in advance, and should be fine. Hope that helps.
Later,
Joe

 

[xjtrailrider]

I put my sensor in the return line just after the cooler, all 4 of my XJ's have the same set-up.

 

[pma4x4]

Heres a thought for restarting and old post.

If you dont know wich line is wich. its simple. detach a line of your choice from the radiator and hook a hose up to it. aim the hose into a bucket. Start (insert any vehicle here) up and have buddy watch and see if fluid goes pumping out of the hose. This will only take a second.

if it shoots out then you get the outline of the tranny.

if nothing then you got the return line of the tranny. bolt it back up and use the other line for the sending unit.

This method can also be used for flushing your tranny.

 

[ParadiseXJ]

So, I have two questions about this.

What is a good temp for the tranny?

Can the radiator be bypassed altogether with an aux. cooler?

I have a small aux. cooler but could use a bigger one, I think, and it just seems like 4 hoses might be 2 too many. If I just plumbed in a larger cooler I could eliminate the hoses to the radiator (possible leaking points) and go with the 2 hoses to the cooler(?).

 

[pma4x4]

So, I have two questions about this.

What is a good temp for the tranny?

Can the radiator be bypassed altogether with an aux. cooler?

I have a small aux. cooler but could use a bigger one, I think, and it just seems like 4 hoses might be 2 too many. If I just plumbed in a larger cooler I could eliminate the hoses to the radiator (possible leaking points) and go with the 2 hoses to the cooler(?).

I think nominal temp is like 160F. but i may be wrong. I would not bypass the factory. if you add the aux cooler you add total cooling surface and capacity.

M2C

 

[bobinyelm]

I think nominal temp is like 160F. but i may be wrong. I would not bypass the factory. if you add the aux cooler you add total cooling surface and capacity.

M2C

I spoke w/ B&M today, makers of many transmission coolers and gauges.
www.bmracing.com

Their tech said that putting a smaller cooler AFTER the radiator cooler is the better way to go. That way, you can use a smaller cooler that won't block so much of the A/C condensor and radiator as well.

I also asked where the best place to put a transmission temp gauge sensor is, because everyone has an opinion on that one: in the transmission output line, in the return line, in the oil pan, in a test plug hole, etc.

He said that hands down the BEST place is the return line, because that measures the fluid the transission will be seeing. The output line measures the torque converter output line, which is likely to be much hotter than the temperature sensitive transmission parts, anyway.

The temperature charts published in so many places showing transmission/fluid life vs. temperature are valid ONLY for the temps reguistered in the transmission RETURN line.

Not saying he's 100% right, but B&M has spent LOTS more time researching and testing than I have.

Here's a chart showing temps vs. Fluid/Transmission Life:
http://www.txchange.com/heatchrt.htm

Bob

 

[Blaine B.]

What about replacing pan drain plug with temp sender for new aftermarket guage? Just crawling around underneath my '98 tonight, looking for a good place to install sender...anyone try this location? good idea / bad idea??

Sounds like a nice area for a rock/foliage to knock it off and send your trans fluid flowing onto the ground:exclamati

 

[tangowhiskey]

Thanks man!

Mine is a 1998 with only the radiator cooler, no aux cooler (yet). So the line that enters the top of the radiator is the line from the tranny, and the line that exits the bottom of the radiator runs fluid back to the tranny, correct?

thanks
nate

Guys, that's not correct! The top line on a '98 is the RETURN. I know this because I just did a flush by putting what my FSM said was the return(the bottom line) into a bucket. To my amazement, fluid started flowing out of the hard line onto my face. The line in the bucket wasn't flowing any fluid. On the earlier XJ's (91-92) the return was the bottom line. This isn't so on the newer XJ's. Don't make the same mistake I did!

 

[LABMBA87]

Ok, 94 with the AW4. I have replaced the radiator with one that DOES NOT have the rad cooler. I have passed everything through the aux. cooler. I have a pod installed on the pillar, and i have my other gauge operating. I need to get my trans temp sensor hooked up. Which one is the return line on my Jeep? Which is the easiest way to hook this turd up.
TIA.
Also, what is the best way to hook up an aux cooler and any rec. on which one to purchase.

Thanks again
Scott:cheers:

 

[pma4x4]

Well, I've got 1800 bucks into my new tranny. I am going to install a cooler and bypass the radiator all together and try that.

I just change my tranny fluid with every 3rd to 4th oil change. I just do a fluid drain from the plug. I know this doesnt get all the ATF but every 9k to 12k wont hurt.

I already got a gauge hooked up. Driving around the mountain grades temp got to 210-220 with sensor on the Out line (into rad)

I plan on trying 100% bypass then maybe before the rad and then after. I may post the results. I may also install the temp sensor on the in and out lines to see that difference too. I figure maybe this way we can tlay this to rest. I am using a Autometer gauge gauge so you know the gauge setup is good.

 

[pma4x4]

Ok, 94 with the AW4. I have replaced the radiator with one that DOES NOT have the rad cooler. I have passed everything through the aux. cooler. I have a pod installed on the pillar, and i have my other gauge operating. I need to get my trans temp sensor hooked up. Which one is the return line on my Jeep? Which is the easiest way to hook this turd up.
TIA.
Also, what is the best way to hook up an aux cooler and any rec. on which one to purchase.

Thanks again
Scott:cheers:

I got a 96 4.0 AW4 I got my sensor tapped into the Outline of the tranny (the top line on the radiator).
I figure if your going to read whats hot read it going out. You have to use a B&M tranny gauge to tap into the 3/8's line
Click here for gauge kit

 

[tangowhiskey]

Most of what I've read, recommends not bypassing the radiator when installing a trans cooler. I would install the trans. cooler in line after the radiator. As a matter of fact, that's what I've done and so far it works great! Just my thoughts on the matter. Good luck!

 

[tangowhiskey]

Ok, 94 with the AW4. I have replaced the radiator with one that DOES NOT have the rad cooler. I have passed everything through the aux. cooler. I have a pod installed on the pillar, and i have my other gauge operating. I need to get my trans temp sensor hooked up. Which one is the return line on my Jeep? Which is the easiest way to hook this turd up.
TIA.
Also, what is the best way to hook up an aux cooler and any rec. on which one to purchase.

Thanks again
Scott:cheers:

I wish I knew what to tell you. All I know is that on my '99, the return is the line that connects to the top of the radiator. I found this out the hard way by doing a radiator "flush" using what my FSM said was the return(the bottom line). Needless to say, it was wrong. I got a face full of trans fluid. Good luck with your project!:repair:

 

[keep0njeepin0n]

I hate to bring back a dead thread, but where exactly is this plug(Picture)? I was looking around, but I wasn't exactly sure which one you were referring to. If anybody could point me in the right direction it would help me out a lot. Thanks in advance.
Joe

Ok yeah this is an old thread. Did you ever figure it out, or has anyone else? I would like to do this SAME thing, but want to make sure it will work properly first!

 

[pma4x4]

To pump a little more life back into this one, I have finally installed my tranny cooler. Even in the AZ heat its running too cool. for on road driving. I expect it to stay in the green while off-roading. as for the cooler climates I will probably install a bypass valve so the tranny stays at temp.

As for the tempo gauge. I found out no matter what. Run a ground wire off the sensor body somewhere. My gauge kept bouncing all over when i would sneeze until I grounded the "T" fitting it threads into.