180 Thermostat Results (With Towing Data)

[bass mechanic]

how do you think it would have towed up a real pass?

I've yet to tow my camper up anything very big along I-70 here in colorado.

i looked up your "pass" and had to chuckle a bit, 3,000 feet is about 3500 feet below where i live and drive daily!

I've been curious to see how the truck does pulling a 7,000 camper up an 8% grade at close to 13,000 feet.

[sugarjohnson]

JonA ....how hard was the thermostat install?

[nando87]

I called Lingenfelter, you can no longer get the old design and they don't make a new design yet. They said that they are around a couple months out still on offering it to the public.

[kstruckcountry]

I would have liked to see a control run (stock), run with only the fan changes, and a run with the fan changes + tstat.

[Jon A]

how do you think it would have towed up a real pass?

I've yet to tow my camper up anything very big along I-70 here in colorado.

i looked up your "pass" and had to chuckle a bit, 3,000 feet is about 3500 feet below where i live and drive daily!

I've been curious to see how the truck does pulling a 7,000 camper up an 8% grade at close to 13,000 feet.

 

 

Elevation is not the most important factor when testing the cooling system of a naturally aspirated engine. The famous Davis Dam grade used by the manufacturers and SAE is about the same height, albeit a bit steeper and usually hotter. Triple digit days can be hard to come by at 13,000 feet.

 

But by all means, please do tow you trailer up the pass on a hot day and log temps. I encourage everybody to log temps this summer and post them in this thread along with a description of the conditions. The more people collecting and posting data the better.

[Jon A]

This is a great write up!

 

I have a BIG problem with heat on my 5.3 w/ 3.42 gears when towing, I've even had my truck tell me to pull over and run the truck at idle due to My Oil Tempe being to high!!

 

This happened about 3/4 up a very long hill pulling about 8-9k going 65mph, there was a lot of traffic and no where to pull over so I couldn't run the truck at idle I just had to back it down to about 55mph and hope for the best.

 

Due to my heat problem I don't want a tune in fear that something might blow and then I'm screwed even though I know the fan change will help drastically!

 

BUT I'm very interested in the thermostat change!!!

 

Do you think by just changing the thermostat will show decent results?

 

 

Yes, just the thermostat alone would help you the vast majority of the time--possibly all the time--towing at highway speeds. While the fans can add a lot of cooling, even at highway speeds, you’re getting a lot of ram air flow as well so most of the time you’ll run cooler temps even without adjusting the fans.

 

You reached some really high temps (well above the stock thermostat’s fully open temp) before and technically you aren’t increasing the capability of the cooling system with only a thermostat, but practically you’ll find it will run cooler virtually all the time on the highway.

 

On the very steepest hill, if it just goes on forever, theoretically your engine will reach the same temperature because you haven’t increased the capability of the cooling system. However, it’ll start out cooler at the bottom and heat up more slowly, so in reality you may find there is just no hill long enough to make you reach the temps you were reaching before.

 

So yes, even if you don’t reprogram your fans you will be helped by a cooler thermostat nearly all the time at highway speeds and there’s a good chance it will keep you out of the danger zone in many of the situations you got too hot before.

 

Of course cranking up the fans in the tune will allow it to help even more, increasing the capability of the system. I know many people still wrongly state that the fans make no difference at highway speeds. This is simply false with the powerful fans these trucks have today. This is not some mystery where there are competing theories. There are facts supported by data, and mis-informed false statements. There has been much testing in the automotive industry so the facts are well known. For example, from SAE 2003-01-0275:

 

 

 

 

At high and very high vehicle speeds and in terms of the heat performance of the cooling radiator :

 

· there is no difference between fan on and off for the low fan system electric power ( < 100 Watts for example),

· there is a clear difference between fan on and off for the medium and high fan system electric power ( > 200 Watts for example), even at high vehicle speeds.

 

 

I haven't measured the draw of our fans at full speed, but given their output they're likely in the 600 Watt range. As you can see from that chart, even a relatively weak 250 Watt fan is still adding cooling capability at 120 MPH. The bigger fans add even more.

 

Higher fan speeds will help your tranmission temps a lot as you have an air/oil cooler in addition to the radiator in-tank (where cooler engine temps will also help).

 

You basically had all three fluids getting too hot, so if anybody really needs to improve the entire system capability, it's you.

[Jon A]

 

 

Do you have a screen shot of the run with the same load up the same grade with the stock set-up?

 

 

I wish, that would have been great! This is the first time I've scanned with VCM Scanner while towing. Most of the time when towing I have more important things to worry about than messing with a laptop. In the past I've kept track of engine temps with Torque on my phone, but I didn't figure out how to get tranny and oil temps from that until recently (my cheap bluetooth adapter wasn't up to the job). Now that I have that figured out I should be able to log temps any time I'm towing.

 

It was my scans when not towing that confirmed under the right conditions it was going to get much hotter than I wanted. Particularly concerning was oil temp:

 

 

 

 

That was unloaded, on level ground on a cool day. It's with the stock thermostat, but I already had the fans programmed more agressively to limit the engine temp to the 220's or it would have easily hit 230+ and who knows where the oil would have ended up. If it does that on a 60 degree day, empty, on level ground it was clear things could get worriesome in the right conditions (towing up a mountain pass in the summer).

 

The problem with oil temp is that it heats up quickly under heavy throttle, but doesn't want to cool down after you let off the throttle. Once the engine coolant is back down to 210, the stock thermostat is basically closed so your oil cooler (in the cold tank of the radiator) isn't doing anything. Even with the fans on full blast, if the coolant flow over it is nil, it's not going to help. Throughout my scans you could see the oil stair-stepping up in temp. Every time you get on it, the oil would increase in temp but it wouldn't cool back down to where it started before the next time you get on it, so the gains would be largely additive.

 

That's why a lower temp thermostat helps the oil temps so much--the higher average coolant flow improves the performance of the oil cooler, even at the same temps. Make the temps of that coolant colder in addition and it's a huge improvement.

[Jon A]

Thanks for the information Jon A. Do you think you could collect this same data but when not towing? I would be curious to see your temps after fully warmed up during normal driving conditions.

 

Yes, actually I did scan up the very same pass a few weeks earlier.

 

 

Not too much of note there, no trailer and it was a cool day. You can see it did need to kick down into 5th (still had about 1000 lbs of payload) so the engine did have a little load on it, but there's no strain on the cooling system.

 

 

I wonder if Lingenfelter could figure out how to replace the OEM transmission thermostat? If the transmission cooler is regulated by a thermostat, one that opens at a lower temp would probably aid in keeping transmission oil temps lower when towing.

 

They could, but I doubt they will. Temps in the low 200's just aren't a worry for the transmission with modern fluid. When I installed transmission coolers on "old school" transmissions in the past, I used a 180 degree thermostat. This one seems fully open at a little over 200 so you have a long way to go until you hurt the modern synthetic fluids.

 

 

Also I was curious what program you are using to collect this data? Looks like some sort of Windows application.

 

 

It's VCM Scanner, which comes with HP Tuners. But if you have an android phone you can log the same temps with the Torque app. I found I needed a decent OBDII bluetooth adapter to work on this 2014 though, while cheap ones had worked on older vehicles.

[Jon A]

I would have liked to see a control run (stock), run with only the fan changes, and a run with the fan changes + tstat.

 

Yes, that would have been ideal but with my work schedule I can only take so much time for goofing off like this. My scans on level ground before were plenty to convince me in a test like this things would get really, really, hot with the stock setup, I just don't have the exact numbers.

 

I'm not going to bother to swap thermostats again until Lingenfelter has the new model available (mine is working fine but I'll want the updated model for peace of mind when available). The only practical way for me to test the stock thermostat now is if somebody else in the area volunteers their stock truck so we could test the two setups back to back, switching the trailer. That would be kind of fun.

 

I do sort of wish now that I had turned around and made another run with the stock fan settings, but I was already late. Maybe next time. I think it would have done fine up most of the grade, but the last few miles where temps started to climb and the fans really cranked up it surely would have reached higher temps, the question is how high.

 

Hopefully this awareness will encourage others to log temps when they tow. Lots of people tow with the stock setup so all they need is Torque on their phone and they can know what's going on. The temp gauge in my Denali reads exactly 210 degrees from about 190 to 230, and there's no oil temp gauge so unless you've gotten really, really hot you'll have no idea what's going on.

[Jon A]

JonA ....how hard was the thermostat install?

 

It's easy, about 1/2 hour. I didn't even bother draining the coolant, I only lost about 1/2 gallon. Of course that 1/2 gallon will make a mess so about 20 minutes of that 1/2 hour is cleaning up the mess (lots of old towels help).

[Jon A]

I called Lingenfelter, you can no longer get the old design and they don't make a new design yet. They said that they are around a couple months out still on offering it to the public.

 

 

That's too bad. And here I got everybody's hopes up..... There is another option, but it's more expensive (comes with a completely new billet housing) and it's only available in 160 degree, and that's the one made by Late Model Racecraft: http://www.corvetteforum.com/forums/c7-tech-performance/3669303-lmr-thermostat-and-billet-housing.html

 

$350 is a turnoff and you don't really want to run a 160 in the winter time so the Lingenfelter 180 is by far my first choice if/when available. However, if I was planning to spend thousands of dollars on a vacation towing a big trailer all over the west this July or August, I would certainly get the LMR and run it. Swap it for the Lingenfelter or stock before winter comes and you should be able to recover at least a couple hundred selling the LMR used. So for around the cost of a tank of gas you could buy a lot of peace of mind.

[07Softail]

JET Performance sells cooler Thermostats.

 

RT

[TJay74]

 

It's easy, about 1/2 hour. I didn't even bother draining the coolant, I only lost about 1/2 gallon. Of course that 1/2 gallon will make a mess so about 20 minutes of that 1/2 hour is cleaning up the mess (lots of old towels help).

 

 

Best and easiest way I have found to do stat changes on the new LSx and LTx series engines. I tae a heavy duty yard trash bag, then I snake it under the thermostat housing and drape it down under the truck. Then I have everything ready, crack open the retaining bolts. Any fluid goes down in the garbage bag, then swap the new stat over and bolt it up.

 

Then pour the coolant back into the system. I don't usually loose any coolant with this method, it is caught in a clean bag and goes right back in the system. Then I let the truck reach operating temp with the reservoir cap off, this allows the system to burp out any air.

 

Has worked every time like this for me.

[Sooperdave]

Great write up JonA!! Really good stuff here! Just keep in mind to the guys asking about doing just the stat... unless you get the fan turn-on temps adjusted in the puter, the stat won't be beneficial sitting in traffic. Must do both at the same time just as JonA pointed out in his test. I sure would like to do some tuning and get a colder stat on mine. Just been hesitant in fear of warranty issues.

[Sooperdave]

 

 

Best and easiest way I have found to do stat changes on the new LSx and LTx series engines. I tae a heavy duty yard trash bag, then I snake it under the thermostat housing and drape it down under the truck. Then I have everything ready, crack open the retaining bolts. Any fluid goes down in the garbage bag, then swap the new stat over and bolt it up.

 

Then pour the coolant back into the system. I don't usually loose any coolant with this method, it is caught in a clean bag and goes right back in the system. Then I let the truck reach operating temp with the reservoir cap off, this allows the system to burp out any air.

 

Has worked every time like this for me.

Great trick! Thanks!