Do you watch your temperature gauge?

[MrUKToad]

Power's not the be all and end all. For the benefit of the OP, we tugged our 2011, 28' International down from Canada to Florida and home via New Orleans last year and used our trusty 2011 3.5L V6 Toyota Sienna. It was high eighties to low nineties Fahrenheit all the way down and the engine temp gauge never once moved away from dead centre. On the trip along the I10 between Tallahassee and Mobile the outside temperature was showing high nineties and I did see a tiny movement north of normal but after a stop for lunch it went straight back down to normal again and stayed there. Sure, there are no real hills apart from the I75 in Tennessee but even so, the TV coped really well. We do have an additional transmission cooler.

[purman]

I use to watch mine, and the transmission temp gage too. But they have never, and I mean never moved. Going up hill in the rockies, heat of the desert, anywhere. They just sit where they normally do.

08' Sequoia 5.7 L tow package.

[perryg114]

Modern cooling systems are way better than they use to be. Overheating when towing was common decades ago. Transmissions can still overheat if additional cooling is not available. I would always prefer a manual transmission for overall reliability. The scanguage II is good insurance. You can see problems before they become real problems. You can see exact numbers not gages that are not calibrated in real units. It also doubles as a code scanner and you can move it from vehicle to vehicle.

Perry

[Jim Flower]

My experience with 2 former Jeeps with the 4.7 L V8 was the same as Chillpoints so I think this is normal for that motor. I always used the tow haul mode and kept the rpm at 3200 to 3400 on hills. I also used Mobil 1 synthetic. The HO version of the 4.7 got much better gas mileage than the regular version. My safari weighed in at 6000 lbs.

[perryg114]

No don't mess with cooler thermostats. That may have worked during the 70's but it can really mess up a computerized engine. Everything is based on that engine temperature.

Perry

Originally Posted by ElCamino Man

I dont think youd see much difference in engine temps by putting in an aux tranny cooler. One thing you could do (as long as it doesnt mess with your computer) is put a cooler thermostat in. I noticed on my F-250 itd get hot if I just let it idle for too long. Replaced the thermostat and viola! Doesnt creep much. I also have an aux trans cooler on mine, but its to keep the tranny cool, not the engine.

And your gauge on your truck would be a dummy gauge. It shouldnt read much difference whether its actually getting hot or not. You could install either an aftermarket gauge, or like stated earlier, a ScanGauge. Then you can monitor EVERYTHING on your truck, including engine and tranny temps. Theyre not bad priced either. I think something like $130

[ElCamino Man]

Hence the reason I said unless itll mess with your computer lol. I was gonna put a cooler thermostat in my 1992 F-250 but the guy behind the counter sad itd prolly be best to stick with the stock one. If itd mess with a 1992, im sure itd mess with a newer one

[mefly2]

Jon-

We went through the same analysis as you did ... finally adding an extra guage (Aeroforce) to our jeep to specificallly monitor transmission temperature (hence, we use the jeep for very limited towing). Although the trans temp generally lags behind the coolant temp shown on the dash guage, your pic looks to be in the acceptable range for temps. As for your other concerns about climbing a lot of hills or long haul mountain driving - we did the same analysis there, too and ultimately decided upon something a bit larger than our 1/2 ton truck. We bit the bullet - so to speak - and opted to replace our 1/2 ton (paid for) with a 3/4 with diesel (still paying) simply for the torque ($$$, yes, I know) - it makes the mountainous driving where we live so much easier and pleasant ... no more string of cars behind us "antsy" to pass ... not to mention HD tires & brakes for safety, tow/haul mode, and compression brake for downhill. We really enjoyed our F150 1/2 ton with the 20' AS, but we agonized at every mountain pass and now - with the 3/4 - those passes effortlessly disappear behind the 3/4.

Where previously, the 1/2 T transmission was always hunting for the right gear (read that heating up) while ascending, the 3/4 transmission rarely even downshifts. There is usually a higher cost in purchase price as well as diesel fuel, however; only you can decide if the mountains will offset those increased costs. For us, it was a no brainer living in the middle of the Rocky mountains. Most TVs are a compromise between superior city vs highway/towing performance. Our 3/4 does not compromise its towing/hauling design for city driving and exacts the toll of higher operating costs with much lower mpg. Yes, we'd buy both the AS and the diesel Ram over again! That comes from an old phart on a penny-pinching verrrrrrry limited income.

[jcanavera]

While having a transmission cooler in front of the radiator will transfer some heat back to the water in the radiator, the radiator has so much more surface area that the amount of heat gained will be dispersed out of the radiator. It's surprising how efficient the radiators are.

The big thing to remember if you add an auxiliary cooler is to make sure you remember that there is an internal transmission cooler that may be part of your engine radiator system. Make sure that the transmission oil output from that cooler is routed to the input of your new cooler. Doing it in reverse will actually reintroduce heat back into your transmission oil, thus voiding the benefit of the external cooler. Typically you can identify the output of the internal transmission cooler by touching the two metal pipes that typically are at the lower portion of the engine radiator. The cooler pipe will identify the output flow from the internal cooler.

My GMC van's factory trailer package includes an external transmission cooler and it is mounted in front of the engine radiator.

I've always either added or had external transmission oil coolers on every tow vehicle I have ever owned. Keeping the transmission changed at appropriate times, towing in the correct gear (follow the manufacturer's recommendations in your owners manual) and use of external coolers has kept me away from transmission issues in my years of towing.

Jack

[jcanavera]

Originally Posted by Chillpoints

So do you watch your temperature gauge? If so what is its range? Of course if you have a huge truck pulling a Bambi your data will not be as helpful as if you are like me pulling a trailer that is closer to the recommended limit of your TV. I am pulling a 29' Excella with a small 4.7 liter V8. Had I known I was going to get an Airstream I would have at least got the 5.7.

Thanks in advance for any thoughts.

Jon

Jon, I do watch the gauge, especially if I am dealing with hilly terrain. What I have found over time is that the pitch (sound) of the radiator fan will noticeably change when the temperature of the coolant starts to approach a high level. On a non electrically controlled engine fan, the sound of the fan approaches what I consider a roaring sound and with the efficiencies of the radiators and fans, it is surprising to watch the temp gauge drop. In my experience I've only seen the fan go into this situation when we get stuck into traffic jams in hot weather on Interstates where you are bumper to bumper and are also dealing with a grade. In those cases the radiators aren't really getting enough air flow and engine temps rise rapidly.

Jack

[ElCamino Man]

Ill throw in a tid bit here thats not completely relevent to the situation:

I was sitting in a line waiting for the bank teller for about 5 minutes and in that time my engine temp rose about 1/4 of the gauge and my tranny temp rose about 40* (its actually got numbers on it). AND Iv got a tranny temp gauge. All just because I was idling! I figure its ok for your gauge to move around. Mine does constantly unless im on the highway and moving at a constant speed (never been over hills either). I imagine your gauge moving up just a hair is normal. More work = more heat. Unless it starts getting close to the red, I wouldnt worry about it

[TomW]

Originally Posted by ElCamino Man

Ill throw in a tid bit here thats not completely relevent to the situation:

I was sitting in a line waiting for the bank teller for about 5 minutes and in that time my engine temp rose ...

I watched my '84 Suburban's gauge like a hawk, and even installed a supplementary cooling fan controlled by me when we were idling because the gauge reading routinely went too high for my comfort.

The Suburban had to be left in the stable this year because its gas bill was killing us.

We're headed out to Disney soon with the Overlander under tow by my '99 Silverado 2500. The coolant gauge, from past experience, will not budge. The tranny temp gauge will show load, but no temperature that will concern me.

Nothing like a light-weight Vintage Airstream coupled to a "new" 3/4 truck for peace of mind during a 13 hour drive.

Tom

[perryg114]

Your like me Tom. If it is less than 20yrs old and has less than 200k miles on it then it is considered new. I think modern aluminum heads and reverse flow cooling has helped a lot with more efficient cooling in today’s vehicles. Reverse flow means the cool water from the radiator goes through the heads and then into the block.

ElCamino Man, Idling puts a ton of heat into the engine and transmission because you are sitting there with no airflow with the torque converter spinning generating heat. I use to warm up my 68 dodge van that way on cold mornings. I would put it in drive and let it idle to warm it up faster. I would also put it in neutral and rev the engine to cool it down a stop lights. The increased air flow from the fan spinning would cool it down.

Perry

[ElCamino Man]

I thought about that after I posted it lol. Soon as I FINALLY got through to the teller and pulled onto the road, it almost immediately started dropping again lol.

[Chillpoints]

Well as usual the Forum is a great resource for information. I guess I know what I am going to be putting on my Christmas List this year. Lets just hope I can get $160 worth of "behaving" in between now and the end of the year so I can get one of those way cool Scangauge things. Then I can watch to see if I should add an additional Tans cooler.

If nothing else I appreciate all the votes that HP is not the ultimate requirement (Thanks MrUkToad). As I mentioned in the original post, I can tolerate the current gas millage I just don't want to go in the hole. Figuring I put over 14,000 miles on the truck this past year and only 1,400 were towing I need to be cautious.

Perhaps the easiest answer would be to do all my traveling in the winter when the air temps are much lower.