What temperature to measure Transmission fluid?

[shahsmerdis]

Hey all,


I searched pretty thoroughly for this question on our 3rd gens but I don't think I found an answer other "measure it after a test drive"

since ATF expands with temp, what exactly is considered hot or operating temp? The average temperature rating of our tranny fluid, or is there a specific range? You can get very different results on the dip stick, without actually measuring the temperature...
after a test drive, at operating temp, i am on the hot/fill line. So I am not really worried. Just wanted to confirm.

Thanks.

 

[mtbtim]

The FSM says operating temp is 158-176. Check to see it's in the hot range on the dipstick when your trans is in that temperature range.

 

[Kotrin]

I known it's on another thread that [MENTION=120071]mtbtim[/MENTION] and I spoke about before, but the light is tied to 260 n or 270 (on my phone so can't find it). The break down is 230 where your oil life goes down hill quickly.

But "hot " is the temperature normal like mt said

 

[jgue467]

... You can get very different results on the dip stick, without actually measuring the temperature...

That is why the trans dipstick has two Fill lines, hot and cold, so Really it is your choice at which to measure, what a country! :cowboy:

 

[mtbtim]

If you can't monitor your trans temp, just do a long enough drive to get it up to operating temperature. I'd drive at least 5 miles one way on a highway or freeway and then drive back to your house to check it. Make sure to shift through all the gears first, put it in park, leave the truck running and make sure you are on level ground. Don't wait around too long because the trans temp will start to drop pretty quick while you're sitting there idling. If you are still at the lower line at the hot range, I'd add a little to bring it up in between the marks or all the way up to the top hot line. Dipstick readings can be a little deceptive. You are looking at reading where the oil on the dipstick is solid, not streaked or partial.

I think people stress out about overfilling and you have to be overfilled by quite a bit to mess up the transmission. From my experience with my own truck and others, you should be in the operating range after around a 10 mile drive on the highway. On the actual highway, your temps will be lower because of the air flow through the radiator. As soon as you get onto the surface streets, your trans temp will go up into the operating temp range.

Hope this helps you out.

 

[shahsmerdis]

If you can't monitor your trans temp, just do a long enough drive to get it up to operating temperature. I'd drive at least 5 miles one way on a highway or freeway and then drive back to your house to check it. Make sure to shift through all the gears first, put it in park, leave the truck running and make sure you are on level ground. Don't wait around too long because the trans temp will start to drop pretty quick while you're sitting there idling. If you are still at the lower line at the hot range, I'd add a little to bring it up in between the marks or all the way up to the top hot line. Dipstick readings can be a little deceptive. You are looking at reading where the oil on the dipstick is solid, not streaked or partial.

I think people stress out about overfilling and you have to be overfilled by quite a bit to mess up the transmission. From my experience with my own truck and others, you should be in the operating range after around a 10 mile drive on the highway. On the actual highway, your temps will be lower because of the air flow through the radiator. As soon as you get onto the surface streets, your trans temp will go up into the operating temp range.

Hope this helps you out.

The FSM says operating temp is 158-176. Check to see it's in the hot range on the dipstick when your trans is in that temperature range.

Hi Tim,

Thank you exactly the numbers I was looking for! I do have the ability to check trans temp with a torque pro app. I Can't remember what exactly those temps were, but I remember them being average once i googled it. I'll do a short drive and monitor the temp till it gets down to that range. cycle through gears and measure.

Yeah, I do agree it does take a lot of effort to overfill or under fill this tranny, at least when compared to dipstickless transmissions. With the price of ATF, and how easy it is to do flushes on this transmission, I can't see any reason why anyone should lose a transmission because of neglect. Its even easier than an oil change.

Thanks a lot everyone !

 

[amalik]

The FSM says operating temp is 158-176. Check to see it's in the hot range on the dipstick when your trans is in that temperature range.

Hey [MENTION=120071]mtbtim[/MENTION]

Can you reference me to what page number in the FSM says that?

I recently installed a tranny gauge, and being a 97, my ECU doesn't send Trans temp so I had to wait this long to get a good idea of my temps.

I was running aux cooler bypassed, but when the gauge was installed, I switched to in-series.

10 mile highway drive is the only drive I've done so far and I hit around 150. Stop and go city should get me a little higher.

My concern is that being in-series and cooling twice, I'm not sure I will even hit the 158 minimum in the winter & I'm wondering if I need to go back to bypassed or stick with the in-series.

 

[alumarine]

Hey [MENTION=120071]mtbtim[/MENTION]

Can you reference me to what page number in the FSM says that?

I recently installed a tranny gauge, and being a 97, my ECU doesn't send Trans temp so I had to wait this long to get a good idea of my temps.

I was running aux cooler bypassed, but when the gauge was installed, I switched to in-series.

10 mile highway drive is the only drive I've done so far and I hit around 150. Stop and go city should get me a little higher.

My concern is that being in-series and cooling twice, I'm not sure I will even hit the 158 minimum in the winter & I'm wondering if I need to go back to bypassed or stick with the in-series.

Page DI-164 Diagnostics

 

[mtbtim]

Hey [MENTION=120071]mtbtim[/MENTION]

Can you reference me to what page number in the FSM says that?

I recently installed a tranny gauge, and being a 97, my ECU doesn't send Trans temp so I had to wait this long to get a good idea of my temps.

I was running aux cooler bypassed, but when the gauge was installed, I switched to in-series.

10 mile highway drive is the only drive I've done so far and I hit around 150. Stop and go city should get me a little higher.

My concern is that being in-series and cooling twice, I'm not sure I will even hit the 158 minimum in the winter & I'm wondering if I need to go back to bypassed or stick with the in-series.

It's in Volume 1, Maintenance Section (MA), Page 9 of my 2000 FSM.

I haven't yet ran my truck in a very cold climate so I'm kind of curious what kind of temps I'll be registering when I visit the snow this winter. I'm hoping the cooler's thermal bypass does it's job well. I would think bypassed setup would be worse for winter since you don't get the benefit of the ATF being warmed while it runs through the cooler in the radiator.

So far, my in-series set-up has worked well to keep my temps down. I did see my temps climb over 230 once but I was carrying 4 adult passengers up a ridiculously steep mountain road, probably a 15-20% grade for a couple miles and the trans temp spiked. I almost stopped to let the trans cool off but we finally made it up to this house where a wedding was taking place. I would hate to have to drive that freaking road everyday.

 

[amalik]

It's in Volume 1, Maintenance Section (MA), Page 9 of my 2000 FSM.

I haven't yet ran my truck in a very cold climate so I'm kind of curious what kind of temps I'll be registering when I visit the snow this winter. I'm hoping the cooler's thermal bypass does it's job well. I would think bypassed setup would be worse for winter since you don't get the benefit of the ATF being warmed while it runs through the cooler in the radiator.

So far, my in-series set-up has worked well to keep my temps down. I did see my temps climb over 230 once but I was carrying 4 adult passengers up a ridiculously steep mountain road, probably a 15-20% grade for a couple miles and the trans temp spiked. I almost stopped to let the trans cool off but we finally made it up to this house where a wedding was taking place. I would hate to have to drive that freaking road everyday.

Thanks.

Yeah I probably will keep the setup for now, but in the back of my mind I know if I don't hit the MIN temp this winter, it will be bothering me.

Most people have an issue with the # being too high, I think I'm the first example of saying it is too low! -- I also need to drive more to collect some data points, maybe it will blast to 180 in city driving.

 

[mtbtim]

Thanks.

Yeah I probably will keep the setup for now, but in the back of my mind I know if I don't hit the MIN temp this winter, it will be bothering me.

Most people have an issue with the # being too high, I think I'm the first example of saying it is too low! -- I also need to drive more to collect some data points, maybe it will blast to 180 in city driving.

Before i even installed my cooler, I was seeing temps in the 130's while freeway driving in 60's weather. So, I wouldn't be too worried because it's running a little low. We're not always going to hit the sweet spot for the ATF's operating temperature but it would be good to be there a lot of the time.

 

[ranchdog]

Thanks for the info guys.

Ranchdog