Ranges for setting up temperature gauges

Hello

I finally set up an android app with the custom PIDs needed to read the transmission temperatures.

Now I'd like to set up the gauges in the app so that the needles show something useful.

Are there generally accepted ranges for the following?

* Casual operating temperature range.
* Heavy load of some kind, but still fine range.
* Getting close to danger, get ready to stop range.
* Turn off the engine right now number.

I'd like to have a set of these for the engine, transmission pan, and transmission @TC temperatures. I looked but couldn't find them.

Thanks in advance.

 

Are these numbers completely unknown?

 

If I were going to set a low temp I'd go with anything under 100, under 100 the torque converter will purposely not lock in order to heat up the fluid. After 100 it will lock up normally. Normally operating temperature for a transmission with a cooler is around 185-195 unloaded since the thermostat opens around 185. As far as a high temp @ColoradoTJ touched on that above, by the time the high temp light comes on your fluid is going to need to be replaced so I would definitely set it below that 304 number. Maybe set the operating range 185-250 and anything over that in the high range?

 

Should not experience that with a Tundra unless the thermostat is pinned open in the winter. Does your 3500 not have a thermostat?

 

Read here.

https://www.tundras.com/threads/transmission-temperature-gauge-range-of-operation.121741/

 

Thanks everyone. I'm going to tow my big trailer for a couple of days on the weekend and will try with the following ranges:

<180 cold
180-250 green
250-280 orange
>280 red

There aren't any mountains around here, and it's not crazy hot these days but hopefully this will give me some useful info.

Without the ranges it's very hard to remember when the temperature got up to what.

 

Have you added an air to oil cooler? Have you been monitoring temps so far? Are you monitoring TC and pan temps?

Main thing to note is when the TC temps are significantly above pan temps, TC is unlocked and creating quite a bit of heat. If you have no cooler, pan temp warms up quickly. It's interesting if you do have a cooler, the TC output seems to flow right into the thermostat so it will open and pan temps will sometimes even cool more as the fluid goes through the cooler.

Point is, keep the converter locked when you can, especially on long climbs. S4 locks up the converter quicker than keeping it in drive, even when in drive with the tow mode on.

 

Came back from my trip today, paid attention to the temperatures. Both at the torque converter and the pan.

Looks like after a couple of hours of towing on relatively flat ground: a low but consistent slope up will bring the TC temperature to 260F. Engine braking doesn't seem to have any effect on the transmission temperatures.

Makes me wonder what they were when I pulled this trailer kilometers up without any breaks in California. I guess they didn't reach 305F because I didn't get any overheat warnings.

No, I don't have a cooler. It's a significant investment and I'd need to see the temperatures get closer to the red line before I go for it. Seems like most here would agree 280F is around where the red line starts. But there are no mountains in Ontario to test it on.

I could see the two temperatures stay the same in S4 when towing flat, but not when climbing - the gear selection seemed to make no difference in that case. And the engine turns too fast for my liking in S4 when going over 80km/h.

 

Its definitely not cheap to add a cooler when you do it the right way and use OEM parts and a quality mount and radiator like the @Genuine Cooling Systems but my rational was that adding a cooler is significantly cheaper than replacing a transmission and something I can do myself. The temperature differences even when not towing is significantly lower.

 

What you are noticing though is the temps go up quickly but are VERY slow to go down.

Just for reference, i went from the same setup as you, running low to mid 200s pan temps just during normal driving. i installed a giant cooler (costs just as much as installing a small cooler...) and now pan temps do not go above 194F even when towing. With the cooler, you will notice that when the TC unlocks, TC fluid output temp goes up, but that fluid opens the thermostat which causes that fluid to get cooled before it hits the pan. When im on the highway, in 6th gear and the TC unlocks up a short rise, my pan temps DROP to the mid 180s (due to the open thermostat). Get back on flat ground, TC locks, thermostat closes up mostly and my pan temp rests around 192-194F. Do what you want, it's your truck, but if you bite the bullet and spend a few hours installing a cooler the difference is night and day.