Trans Temps while Towing

I recently got a Scan Gauge III for the sole purpose of monitoring my Trans Temps while I tow.

My truck is a 2021, CM, SR5, 4x4

The Scan Gauge shows 2 temps for the Trans. A/T Oil Temp 1 and A/T Oil Temp 2

Here is what I am seeing, and hope this is normal

Regular driving around town/freeway (NO TRAILER) after about 20 minutes driving, the Temp 1 is around 210-215, and Temp 2 is 220-225

Last week, I was towing a trailer (about 6500#) through some short hills, and the Temp 1 got up to 230, and Temp 2 was over 250 in a few cases.

I notice the Temp 1 does not flucuate too much, the but Temp 2 will go up and down by 20-40 degrees, especially if the RPMs increase under load.

Long story short, I just want to make sure what I am seeing is normal.

Thanks!

 

I just got a OBDlink MX+....so I'll be following this as well.

Just playing around with mine and deciding what gauges I want displayed and what the max/min should be.

 

Just going uphill will heat the AT temp, our truck don’t have AT cooler, if you tow I think you should get cooler kit.
Pic is going up the grapevine to LA
Edit
Not towing anything, only like 200lbs in bed

 

Are you towing in D? If so, any improvement if you shift to S4?

 

Being in either S4 or S5 this locks the converter and helps keep temps down. just an fyi

 

in my 2015 normal trans temps are ~195. With a 3500lb TT in S4 i still hover at 195-200, the highest I've seen was on a climb in Colorado and it only rose to about 206. I have a Scangauge II.

 

I don't have mine pinned but just cruising around on a regular day with temps in the 90s my trans gets to 190°

 

Fairly normal from what I see with my 2019, whether it is good or bad is another issue. I tow a couple different trailers, 1.5k and 4.5k. The TC temp, Temp 2, does spike all over. It’s the other one, Temp 1, the pan or actual main tranny that I understand is the one to watch and/or worry about.

There is a very recent thread here with very well documented temps and an oil analysis at around 30k miles. Temps he got were similar to yours & mine, and oil was analyzed and good. Mine has 50k on its tranny oil and will be sent in for testing before we hit 60k. I am expecting it to be good. If it’s not, I’ll install the tranny cooler.

The suggestion to try S4 is a good one. If I am not on flat straight road, it keeps my temps down.

 

Pinning def helps from what I've seen.

 

I just don't want it running too cool as I have zero issues shifting gears.

 

OP, go to post 18. Ignore the temp info posted by the earlier model guys above, they have a cooler. It’s 19-21 model years, iirc, where they have not added a cooler, you want to pay attention to for comparison purposes. These years have that small puck that functions as a warmer and cooler of sorts and give the higher temps.

https://www.tundras.com/threads/green-thunder-oil-analysis-thread.94464/

 

I think 1 is AT pan temp and other should be torque converter, TC will move quick and pan temp is slower to temp change

 

Thanks! I just read the thread, and appreciate the details!

 

I am assuming you don't have @Genuine Cooling Systems kit installed. Without it those numbers are consistent without the cooler kit.

 

Nope, no trans cooler, stock vehicle.

 

Looks about right. In the interiem you can change out the fluid at more frequent intervals if you don't want to add a trans cooler system. I do recommend the kit he offers, it is mostly OEM parts and does a great job keeping temps down around ~200 or there abouts.

 

it's normal since you don't have the trans cooler.

I was doing 230 on my daily drive in Houston.

now, after cooler, I hardly ever reach 195

 

Looks normal to me and similar to what I got before the cooler install.