Transmission temps while towing

Its a great guide but just curious how they came up with it.

 

Is this for pan temp or the TC temp? And is this average opposed to a spike?

 

https://www.tacomaworld.com/threads...l-toyotas-write-up-with-many-pictures.526283/

 

I actually saw somewhere that the test was for 1 hour at that temperature. But can't find the reference yet.

 

I can see temps up to 240 and will pull over at 260. I have a large double row external cooler with a aux fan on it.
All measured from my ultragauge.
my route has a few 20mile 9% grade sections where i see the most heat, also towing around 75mph lol.

 

I have a huge external cooler also and have seen 230 but that's at the torque converter. Once I crest the hill it drops ridiculously fast, like 20 degrees in about 10 seconds.

 

If only we were all aircooled! Beauty Bug!

 

I emailed the tech at Mobil Oil to ask that question, as I would see spikes to 200 going up hills without towing and 220 towing... with an aftermarket tran cooler.

Their response was that was for the average temp. They specifically stated that a short-term spike would have no material impact on the life of the tranny fluid effectiveness.
The above being said I start looking for pull over for a cool down idle as I start to approach 220-230 to avoid hitting 250.

 

That is good news. I see 200 frequently and even 220 just going up my driveway with only me in the truck. Getting a big LPD cooler installed soon.

 

I still got significant spikes after I install my cooler (I believe and LPD). Originally a 14k btu, then a 28k btu (if memory serves correct). While I did still get spikes of near the same amount it cooled quicker, and more importantly, when just running down flat roads in 90+ Texas heat towing a small (3500#) trailer my general temp stayed about 170-180.

 

Highest I’ve seen is 230 pulling my 3700lb camper up the escarpment on 1-26 south of Asheville. I monitor it with a Scanguage.

 

Coming and going from Phoenix to Flagstaff pulling about 5000-5100# TT I hit 240 at the torque converter several times during 6-7% grades. Was only there for a few minutes and was always about 20 degrees cooler at the pan. This is using an ultra gauge. Outside temps were mid-high 80s. Hit a 13 mile stretch of 6% grade with a few breaks in it so no continuous strain. Planning on a bigger external cooler, currently only have the small factory one.

 

I see 230 pulling a 5200 lb trailer up hills. That’s at the torque converter. And it takes a while to get it there. Barely over 200 at the Pan. Once over the hill it drops 15-20 degrees within about 10 seconds. But I have a large aftermarket cooler.

EDIT
I guess i already said this but left out trailer weight.

 

Picked up my trailer today and towed it 1hr 50 minutes home and was up hills, down hills and flat roads. My scangauge TFT was fluctuating around 190-215 throughout the drive home. I have a transmission cooler but the factory stock small one. Should I upgrade and if so can I have a secondary one on a switch to turn it on when I need it when towing and switch it off when not towing? Bedsides TFT what else is on your gauge for towing on your scanguage?

 

I monitor my real time mpg and average mpg.

 

Here is mine

 

what unit is that? I hate the AT pan and AT TC?

 

iPhone running ODB Fusion

 

So a bluetooth OBD scanner like the $32 Veepeak plus the $4 Fusion app will give you this functionality?

 

Yes. And more if you buy the extended Toyota set of data. I think its $10 more but well worth it.