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nate379

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Discussion starter · #1 ·
I got a tranny temp guage for the ZJ.

Where's the best place to put the sender? The instructions say the return line. Seems that it would give a cooler than actual reading?

Would it make more sense to put it in the pan? I've got a drainplug I can use... the sender will screw right into the drain plug. I'd mount in on the side of the pan so it doesn't get ripped off of course.
 
The guy that built my 46re told me to put one in the pressure line headed to the cooler. That gives you the truest reading of the temp in the tranny. The temp of the fluid returning from the cooler could be interesting, but doesn't tell you much. I haven't added it in yet though. What gauge and sender did you go with?
 
nate379 said:
I posted this on the local board as well and was told the return line so you know the temp of the ATF that's being fed into your tranny. Makes sense.
Yes... you want to see the temp of the fluid going into the tranny. How are you planning on installing the gauge into the line? For my Dodge Ram I found a "thermowell" that splices into the line and has a tapped out well that the sensor goes into.
 
Discussion starter · #8 ·
I emailed John at IPT and he said to put the sender on the cooler side, as that is the most accurate.

Really I don't think it matter so much on the return or feed lines as long as you know how to read it. I think I'm going to run it to the feed. It will read hotter, but that will be the highest the ATF will get to.... the best way to make sure I'm not burning it up.
 
A little off subject, but I noticed in my service manual there is a line in the wire harness for a 46RH (probably others too) for tranny temp.
Does anyone know if this is an actual temp or just something for a overheating issue?
 
MaineZJ said:
A little off subject, but I noticed in my service manual there is a line in the wire harness for a 46RH (probably others too) for tranny temp.
Does anyone know if this is an actual temp or just something for a overheating issue?
That wire is from a thermal switch in the tranny. It turns on when the trans hits a certain temp, to tell the ECM to take the tranny out of OD, to help cool the trans.
 
For when you get the gauge installed-

The approximate life expectancy at various temperatures is as follows:


175°F 100,000 miles
195°F 50,000 miles
212°F 25,000 miles
235°F 12,000 miles
255°F 6,250 miles
275°F 3,000 miles
295°F 1,500 miles
315°F 750 miles
335°F 325 miles
355°F 160 miles
375°F 80 miles
390°F 40 miles
415°F Less than 30 minutes
 
Cue-Ball said:
What temp does it usually run at on the Grands??
I don't know. One thing to keep in mind is that adding more weight, going up hill, taller tires, ambient temp, driving style, trans cooler efficience and lots of other factors affect the temp. Rule of thumb is 'cooler is better'. Slap on the biggest cooler you can fit and have at it.

Sending units need to be placed on the tranny output to read the actual temp the tranny is getting up to.
 
Discussion starter · #19 ·
I don't think it really matters where it's at as long as there's a good flow of ATF going to it and you read the guage accordingly. I'm going to put it on the feed line so I know how hot the ATF is getting.... not what it's getting cooled to.

Part number... go to jegs.com and search for B&M tranny temp gauge. Summit has the same one as well.

I would imagine stock the ATF couldn't be cooler than around 200-210* when it's all warmed up.

I have heard that backing up will cause a tranny to heat up pretty quickly. I'm sure "rocking" when your stuck can be good either.
 
nate379 said:
I don't think it really matters where it's at as long as there's a good flow of ATF going to it and you read the guage accordingly. I'm going to put it on the feed line so I know how hot the ATF is getting.... not what it's getting cooled to.

Part number... go to jegs.com and search for B&M tranny temp gauge. Summit has the same one as well.

I would imagine stock the ATF couldn't be cooler than around 200-210* when it's all warmed up.

I have heard that backing up will cause a tranny to heat up pretty quickly. I'm sure "rocking" when your stuck can be good either.
Along with keeping it in a stall condition i.e. stopped at a light in drive.
 
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