Temps when Towing and Scan Gauge

I see lots of threads and posts about coolant and tranny temps when towing. I have a 2009 4x4, with tow package, live in the Sacramento California area where summer temps range from 90 to over 100 routinely. I tow my 3000+ boat all over in the summer all over the hot valley and sometimes up into the foothills and mountains. Up until recently I towed in D because I didn’t know I should be towing in 4. Now I tow in 4. I do not have scan gauges. Not one time in the nine years that I’ve owned the truck(bought it new) has my truck ever over heated. I have my tranny fluid changed every 30,000 miles. Just had the 90000 2 days ago. I asked my mechanic about what he found including the condition of the tranny fluid. All 3 times I was told the fluid looked just fine and no abnormal smell.
My point is I think having scan gauges may be more a problem and hassle than a benefit. It seems if you have them you are constantly checking them and worrying about the temps. It’s like OMG the coolant is 210 degrees and you keep your eyes glued to the gauges wondering what’s going to happen. Creates more anxiety than anything.
Before my current taco I had a Tundra, before that another taco and prior to that a Ford 150. I pulled heavy loads , boats and travel travel trailers numerous times in 100+ heat. Never had an engine over heat, never had a transmission problem due to fluid failure due to heat.
So for me at least I don’t think I’d be any better off having the gauges. What ya gonna do if your driving through the Mohave dessert and your scan gauge shows coolant 215 degrees and your tranny 210 degrees but the truck is running just fine. If you have one or want to get one I say fine, go for it. Just my 2 cents worth.

 

Valid points! Personally, I do it because i really like information. Hell, I use my GPS to go to my sister-in-law and I know the route well...lol. I don't think that many change out their transmission fluid that often, I know that I haven't. I am at 65k, so I probably should soon. I have never had to do that in my past vehicles, but this is the first truck I have owned and the first time I drive in sand and tow (which causes more heat). So i am not used to doing that.

 

Yes, valid points you're making. I do have an Ultragage and mainly use it to monitor engine and transmission temps. I think your service interval on the transmission is keeping it healthy with all the towing you are doing.

 

I see your point, and it reminds me of our family camp outs;

My BIL has a 2006 trd Sport, they have an 18ft trailer ~4500lbs.
We had a 2005 trd Sport, now a 2017 trd Sport with a 19ft trailer ~4500lbs.

They have the most basic brake controller and the wd hitch from the trailer place.
I've got a SGII, WDH, tekonsha P2, Friction Sways, extra fuel, strategic loading to keep weights correct, half water tanks, etc, etc, and soon adding ride-rites.

They pay no attention to anything and arrive at the campsite, I've only recently convinced them to tow in 4th.
We arrive and I've analyzed each hill section, mpg, temps, gear choices, etc..

I couldn't travel the way they do, and I don't think they could stand my way.. but everyone has a good time and then we all go home.

 

I actually would like to get a scan gauge , most things like that I’m all in for. But I know me. I once had a Ford truck which on warm days the temp gauge always ran close to HOT. If it was warm out and if I was pulling my boat or not the gauge would stay real close to the red zone. No matter how hot it was outside it never once over heated. Never. But on trips especially when pulling the boat I’d be glancing at that gauge every minute and worrying it was going to over heat. This went on for years until I finally sold the truck. Caused a lot of anxiety. I’m sure if I got a scan gauge every time the temps started to rise I’d be staring at it and worrying. Sometimes ignorance is good.

 

I trust the scan gauge more than any idiot light.

I don't obsess over them any more than a pilot with all his gauges.

Your maintenance and modest load are your keys to your success.

 

I bought my SCII for trans temps while towing. When abusing the truck when towing it gives me the information about my driving and it’s effect on trans temps. IMO it is better to know what temps you are seeing in case it all of a sudden spikes or you encounter conditions outside of your normal driving.

Now that I have towed a few times with the SCII I forget it is there until a situation arises where I want to know my temps and I look and then move on. There is no constant staring at it for days on end. If the OP doesn’t want a scan gauge then don’t buy one and there is no need to start a tread just to tell us that you don’t want one. That is unless you need validation from strangers on the internet.

 

A little uptight there Ex. I started the thread because things are a little slow and thought some may find the topic of interest. I stated I wasn’t getting the damn gauge. I wasn’t looking for nor do I need validation from you or anyone else on the net. And finally who appointed you king? You have no business telling me or anyone else what thread to start or not. If you don’t like a thread or post just move on, ignore it.

 

Lol. We get it you don’t want a scan gauge.

 

Future headline- "Any good transmission shops in Sacramento"

 

A much cheaper way to do the same thing is to use ScanTool 427201 OBDLink LX Bluetooth and the free Android ap Torque. You'll get out for about half the price ($68 vs $158) and you can use your dash mounted phone, which will be busy 90% of the time with maps and phone calls.

 

I went that route, because I have a phone, I bought Torque Pro years ago and still had the OBDII dongle sitting around. I found the PIDs and set up Torque Pro to display both trans temperatures. Towing my 2400# (dry) A-frame in 90-ish degree weather, the highest temperature I saw was about 218, but it quickly cooled down. Average was somewhere around 197. I found the transmission handled shifts and temperature just fine. The higher temperatures happened when accelerating hard.

I commonly towed in D and the transmission would mostly be in 4th or 5th, and would rarely ever hit 6th. Any demand for power was met with a swift downshift.

 

I think a lot of guys like the piece of mind knowing they aren’t torching their tranny. If you wait unil the transmission light comes on you’ll want to head right to a trans shop. Also towing a boat is a different animal than a travel trailer being that wind is more of a factor when towing a TT. My 2016 runs between 190 and 199 degrees on my drive home from work and pretty much the same towing, with a few spikes to around 210. The cooling systems in newer vehicles are incredibly efficient also. So is it necessary to have a scanguage? Not really but I’m sure glad I do because I wouldn’t have the info otherwise. Guages shouldn’t stress you out they should make you relax because you know when you’re doing damage and when you’re not.

 

As an engineer, I view the transmission as the weak point of the drive system. At least to me, the automatic transmission is a lot more likely to overheat and give up than the drive shaft is to snap!

Taking that thought one step further... Since a transmission failure will most likely be preceded by overheating, how fast the ATF temperature rises is probably based on how far over the limit the truck is loaded. If that is true, then it is also fair to assume that under-loading the truck supplies a reverse effect. That is to say, if you are 1500# under the GCWR your chances of transmission failure on a steep 20 mile grade are much, much better than if you are only 100# under.

Of course it's much more complicated than that. GCWR doesn't take into account aerodynamics of the load. But if you're shopping for a trailer, then you probably want to look at trailers 1/3 to 1/2 the TWR, knowing that after people, food, and tools are loaded you still need some safety margin.

Just thinking out loud.

 

I like my scan gauge. Just a little peace of mind for me nothing more

 

Thinking further, to reduce the rolling friction (ie transmission load) AND tire wear it's probably best to also monitor the trailer tire pressures and temps realtime as well. You can now get Bluetooth valve caps to do this. If you haven't seen this, check it out...

https://www.amazon.com/ZEEPIN-Monit...pID=41pIGCblRdL&preST=_SY300_QL70_&dpSrc=srch

They also have 2 valve stem models for motorcycles that would work great on a 2-wheeled trailer.

 

I tow frequently and use an ultra gauge to keep an eye on temps, with this chart in mind that I think others commonly refer to as well:

HOWEVER, this chart, I'm under the impression, is formed with conventional trans fluids in mind, our trucks use a higher quality synthetic WS fluid, personally I use The Valvoline Maxlife stuff which is WS compatible. These newer fluids are capable of higher temps. I don't remember the thread offhand but there was a good one a while back about this. Someone had even contacted Valvoline to say hey I had my transmission up to 240* for a half hour! Should I worry? And Valvoline essentially said meh don't worry about it, this fluid can handle it.

So I'm glad I can monitor the temp, but I don't stress too much, mostly use it to monitor the effect driving habits have on the transmission temps same as @Exracer2 , and like OP, I change the fluid every 30k and it has always looked great.

 

I'd be interested in seeing if Valvoline could release a chart like the one I posted, but as it pertains to their fluid. Maybe it's out there but I've not seen it.

 

What temp do you guys pay most attention too on your ultragauge? Torque converter or pan temp? My pan stays about 20 degrees cooler than the TC(obviously). But if my TC is at 235 degrees ad my pan temp is at 215, do i need to be concerned?

 

Just towed and drove about 9500 miles cross country with my 2015 Acess Cab and a 3500 pound a frame pop up. I really appreciated the Scanguage data. Proof that my set up, inclusive of the regear to 4.56 and additional Tru Cool #45000 Gvw. transmission cooler was working as or better than expected. High altitude passes saw increased temps up to 215 and water temperatures of 210 were pretty common in hot and dry conditions. It was a comfort being able to have real time accurate data and a quick occasional glance when scanning the guage cluster was sufficient to provide the info. I never gave the Scangauge ....more than just a....scan. .....