Normal Trans Temp ?

[Doupe]

I just installed a EGT, and Trans Trmp in the cab, The trans temp is connected to the probe in the trans cooling line, I suspect the outgoing side. I have't towed yet after the install, but notice the trans temp is about 205-220 degrees, is this look normal?, and how hot is hot?, the gauge shows red at 280. There is also a warning light from the factory on trans temp, I wonder how hot it has to be for that to come on?

 

[ScottLewis]

That sounds way hot unless you are under a severe load. I try to keep mine (on cooling line from trans) below 195 even when towing uphill with 11K behind me.



Dan

 

[PJay9]

I just installed gauges and the transmission temp doesn't come much above 100. I installed a BD TC and VB plus a hytec finned pan, using stock trans oil cooler. Is this sound right? I had a 11' Lance camper aboard and running I-5 at 70mph even up hill it barely moved from 100... is it working? The sensor goes in the back of the pan about half way up. Maybe the fluid isn't touching the sensor. I don't know what it did before as the temp was installed after the trans stuff. Also the EGT before the turbo was reading 750 unless I put my foot in it on an on ramp uphill and it would go to 1000. I like that!! PJ

 

[JFaughn]

It sounds like you connected up to the stock sensor in that line , if so that will not work , that sensor is just to tell the computer that the temp is about about 40*F & then it will shift into OD & Lock Up .
On mine I put a 1,000 ohm resistor connecting the 2 wires for that sensor & then put in a sensor rated for that gage , just run easy till you know that its warmed up .
You should put up your truck info in signature , so its easier to answer ???

 

[Edgemann55]

I have mine on a Mass Diesel Line on the output side to the cooler. I read 150-175 no load. Seems like your temps are high. Forgot to add that I have a Mag Hytec DD transmission pan and run Amsoil atf fluid.

 

[PJay9]

It sounds like you connected up to the stock sensor in that line , if so that will not work , that sensor is just to tell the computer that the temp is about about 40*F & then it will shift into OD & Lock Up .
On mine I put a 1,000 ohm resistor connecting the 2 wires for that sensor & then put in a sensor rated for that gage , just run easy till you know that its warmed up .
You should put up your truck info in signature , so its easier to answer ???

It is actually a sensor going into the back of the Hytec pan about the middle top to bottm and side to side. I have been working on the signature stuff yet it doesn't seem to come up, what am i doing that doesn't get it there? HUMMM!! PJ

 

[JZellers]

I have mine in a Mass Diesel line also and with the TC locked up it doesn't get above 195 towing my boat (12K). Empty it rarely gets above 180. However, when towing I can easily get between 220 and 250 in stop and go traffic just before the TC locks up. Then it drops quickly to 190 or so. I agree with everyone that your reading is high. It could be the gauge or sender that's out of whack causing the high reading.

 

[PBrauer]

I just installed a EGT, and Trans Trmp in the cab, The trans temp is connected to the probe in the trans cooling line, I suspect the outgoing side. I have't towed yet after the install, but notice the trans temp is about 205-220 degrees, is this look normal?, and how hot is hot?, the gauge shows red at 280. There is also a warning light from the factory on trans temp, I wonder how hot it has to be for that to come on?

With the sender mounted in the outgoing line to the cooler, your temps will vary dramatically as the TC locks and unlocks. Those temps could be fairly normal in traffic but that's a little high for cruising down the highway. "Hot", in my opinion, is anything approaching 250... I don't know when damage will occur, that's just the worst I've seen on mine, under the worst performance/conditions. I would like to never see anything over about 220 without a good reason.



With all stock trans parts my temp stays between 180-190 under all loads, including extreme loads, as long as the TC stays locked. As soon as it unlocks, it can climb to 250 in seconds... literally, like 10-15 seconds. Once the TC locks up again, it goes back down almost as fast as it went up (prob 20-30 seconds). It's actually kind of scary wondering what temps I was hitting before I got the gauges. I am pretty sure I have other problems (TC/OD Sol, GR Sol or T-Ducer) but there's no question that you want that TC locked up as much as possible.



Try cruising at 55-60 for a good ten minutes or so. It should sit still enough to tell you what's "normal". Unless you suspect a trans problem then I'd consider anything over 190-200 to be a gauge error... Remember, the "cooler" is actually a heat exchanger. Until the trans fluid exceeds the engine coolant temp, it's actually heating the trans fluid, not cooling it. If you idle in "Neutral" on a "mild" day, your coolant and trans gauges should eventually read about the same thing.

 

[PBrauer]

I just installed gauges and the transmission temp doesn't come much above 100. I installed a BD TC and VB plus a hytec finned pan, using stock trans oil cooler. Is this sound right? I had a 11' Lance camper aboard and running I-5 at 70mph even up hill it barely moved from 100... is it working? The sensor goes in the back of the pan about half way up. Maybe the fluid isn't touching the sensor. I don't know what it did before as the temp was installed after the trans stuff. Also the EGT before the turbo was reading 750 unless I put my foot in it on an on ramp uphill and it would go to 1000. I like that!! PJ

This is exactly what mine did when I first installed it. It would move up and down a little but never go much above 100. It turned out that the place I chose to mount it in the line wasn't grounded. I was downstream of the rubber section and apparently the adapter to the cooler is either non-conductive or the cooler itself isn't grounded. I improvised a fix but don't know if I'd recommend it to others... several wraps of stripped wire molded/sealed to the line with plumbers/epoxy putty... works great now.



Try warming up the truck and touching a known good ground to the body of the sender... see if it goes up to 150+. That sender would eventually show the air temp inside the pan, even if it's not submerged, so something's definately wrong. Your problem is most likely a bad ground at the port it's mounted in but there's also a chance that the pan itself isn't grounded. The gasket's a very good insulator and the bolts might only be touching paint. The vendor/maker/seller of the pan will probably tell you the best way to solve this.

 

[RMalone]

I am reading mine in the mag-hytec pan also, and running empty (about all I do) the highest I have seen was about 170degF in 98deg temps at 75mph continuous (eastern Montana is nothing but continuous). Normal ambient temps and unloaded usually don't get to 140degF.



Before you freak out though, I would get another thermo-couple and make sure, those suckers can and do fail and a brand new dud isn't unheard of either. I have seen thermo-couples fail on furnaces (forced air and boilers), water-heaters, guages on my truck (right now the SPA guage in my truck is telling me that my trans is at 274degF!!, even after a night of sitting) I just havent gotten around to getting a new one.



What kind of temps are you seeing when you first start the truck in the morning??? They should be real close to ambient. Do temps gradually go up or do you go from 110deg to 220deg real fast?? I doubt your actually running around empty with 220degF measured in the pan, that would be at least 250deg measured post transmission/pre-cooler. I would think you would have smoked the trans while towing if you actually had those temps while empty.

 

[RMalone]

I posted without reading the last couple posts, dumb on my part. Bottom line, I would definately look at a guage issue first.