40 mph uphill? Other Armada or Titan TVs?

[PaulandAnn]

I’ve been trolling this site for a year. There’s so much info I that haven’t needed to ask a question until now!


Tv: 2006 Armada LE 5.6L DOHC V8 with factory tow package. Tow rating 9000lbs. 305/385 hp/tq
105K miles, added external trans cooler, bypassing in-radiator cooler. Andersen WD hitch which I’m very happy with.

The Armada handles the trailer nicely, it’s the lack of power on the hills that makes the drive so stressful. I chill out once we're through all the hills.

Trailer: 21 ft Jayco. Factory weight with propane: 4385lbs estimate another 350lbs water, a couple hundred lbs food and whatnot. Lets say 5000lbs. (I've weighed the loaded tongue, but not the entire trailer)

(TV cargo: only 2 people and dog)

Driving up out of Phoenix to higher cooler elevations there are several hills/ridges on our way to 7000ft elevation. On every one, I eventually slow to 40mph. Is this normal? Neither trans or engine overheat. I have learned to ignore the “Tow Mode” and just downshift manually to get higher (3000-4000) rpms, for more power and lighter load on torque converter (keeping the trans temp down).

But meanwhile, monster 5th wheel “houses” fly by at 65mph on the same hill towed by their Cummins powered or whatever pickup trucks.

I don’t want a pickup truck. I don’t need one. In our SUV at all times, we have 2 child seats and a large dog crate.

I see the 2018 Ford Explorer with 6 cyl turbo Ecoboost has nearly 100lbs more torque and a 10 speed auto trans. Sounds nice, maybe what I need, but still too pricey.

Are other Nissan owners faring any better than me?

[BarabooBob]

I had a Damon RV built on a Toyota one ton frame. I could top most hills at 45 mph without floorboarding that thing. I just downshifted early and kept that little 22Re engine at 5000 rpm's on the big hills. the engine had a red line near 5500 rpms si U was well within allowable conditions. I could pass vehicles with twice the horsepower because they didn't downshift and keep the rpms up. I drive my F150 with Ecoboost the same way. Let it spin and the engine is happy, the temps stay down (engine and tranny) and I am happy.

[SkiMore]

I'm assuming a gas engine will benefit from a turbo also.

[boggerr]

richclover wrote:

Huntindog wrote:
Not really totally true. Although a turbo MAY not keep all of it;s ability to increase power at high altitude, it will ALWAYS do better than a naturally aspirated motor. There are some variables in turbo systems on motors.... A variable vane turbo is one. The other is sizing. Many turbos control excess pressure by means of a wastegate that bleeds off excess pressure.... at altitude where there is less pressure, it will bleed off less if at all.

boggerr wrote:
Where is everyone getting the info that a turbo is the answer? A turbo diesel at higher elevations is going to lose turbo efficiency. Less air, less combustion temps = laggy turbo,

RPM’s is the answer. Run higher RPM’s on hills and watch your gauges.

I respectfully disagree. At my house elevation, 7000’ MSL, normally aspirated engines, lawn mowers to piston engine airplanes develop no more than 75% rated horsepower. That’s why I flew a turbo-powered airplane rated for 31” manifold pressure to 20,000’ and tow with a Ram Cummins Turbo Diesel 😉

Huntingdog has it right, IMHO.

I’m not disagreeing that a turbo will do better than a N/A eninge but I want the OP to understand that having a turbo is still going to feel the effects of higher elevations and downshifting is going to play a big factor on a turbo enonge.

Yes, VGT turbo and turbo sizing makes a huge difference but still need the higher RPM’s to keep those turbos spooling. As far as wastgates go, they are not opening at higher elevations cause of less air and less boost which equals to less horsepower.

So you think a turbo diesel truck or car is making the same HP at sea level vs one at higher elevation? What did that turbo plane do for RPM’s

[bartlettj]

The other reason those turbo diesels are doing better is the torque curve. They're making double the torque at half the rpm of your Armada, and taking better advantage of the available gears and not worrying about not flooring it or the revs.

[richclover]

Huntindog wrote:
Not really totally true. Although a turbo MAY not keep all of it;s ability to increase power at high altitude, it will ALWAYS do better than a naturally aspirated motor. There are some variables in turbo systems on motors.... A variable vane turbo is one. The other is sizing. Many turbos control excess pressure by means of a wastegate that bleeds off excess pressure.... at altitude where there is less pressure, it will bleed off less if at all.

boggerr wrote:
Where is everyone getting the info that a turbo is the answer? A turbo diesel at higher elevations is going to lose turbo efficiency. Less air, less combustion temps = laggy turbo,

RPM’s is the answer. Run higher RPM’s on hills and watch your gauges.

I respectfully disagree. At my house elevation, 7000’ MSL, normally aspirated engines, lawn mowers to piston engine airplanes develop no more than 75% rated horsepower. That’s why I flew a turbo-powered airplane rated for 31” manifold pressure to 20,000’ and tow with a Ram Cummins Turbo Diesel 😉

Huntingdog has it right, IMHO.

[Huntindog]

Not really totally true. Although a turbo MAY not keep all of it;s ability to increase power at high altitude, it will ALWAYS do better than a naturally aspirated motor. There are some variables in turbo systems on motors.... A variable vane turbo is one. The other is sizing. Many turbos control excess pressure by means of a wastegate that bleeds off excess pressure.... at altitude where there is less pressure, it will bleed off less if at all.

boggerr wrote:
Where is everyone getting the info that a turbo is the answer? A turbo diesel at higher elevations is going to lose turbo efficiency. Less air, less combustion temps = laggy turbo,

RPM’s is the answer. Run higher RPM’s on hills and watch your gauges.

[boggerr]

Where is everyone getting the info that a turbo is the answer? A turbo diesel at higher elevations is going to lose turbo efficiency. Less air, less combustion temps = laggy turbo,

RPM’s is the answer. Run higher RPM’s on hills and watch your gauges.

[time2roll]

I see 2006 Armada makes 305 HP at 4900 rpm and 385 lb-ft torque at 3600 rpm.

When running hard I would probably hang around 3800 to 4800 rpm with that motor for as long as it takes. Usually just above peak torque will feel like the sweet spot for max power. With mine I often pull the lever to hold the gear and set the cruise control by the tachometer to just hold the rpm steady up the incline.

Running steady at full throttle up an incline is often the best part of the drive... for me. Back in the days of drag racing I would get to run full throttle for only 12 to 15 seconds. Running full out for a full 12 to 15 minutes is that much more satisfying.

[naturist]

PaulandAnn wrote:
{snip}
Thanks again, I'll try and chill at higher RPMs.

ps
A word about tow mode: Once I was cruising along in Drive at 60mph, on a long straight gentle rise. I looked down and the trans temp was nearly pegged. I down shifted manually and the temp dropped right down. So in tow mode by itself, evidently, I was cooking the torque converter.

Yup. Especially important if the water pump is mechanical. When making heat, you need the water moving as much as possible to get that heat to the coolers. Don’t fear the gears. That’s why God gave them to us, to use when we need them. Also never fear taking an engine to high revs, especially a gas engine. The only reason the red line is only 6,000 rpm is because they used cheaper valve springs; not enough pressure to close the valves fast enough at high rpm. If you need the power of 4,900 rpm, use it without fear.

[naturist]

1320Fastback wrote:
Completely normal for a unboosted gas engine at altitude. Just downshift to keep rpms up, watch your temps and let the big guys get the tickets and clear the way.

Engines without a turbocharger lose power at altitude. Turbos were invented to solve this very problem for aircraft engines. The higher you climb, the more power they lose. Folks who want to drag heavy loads around in the mountains are well advised to buy turbocharged tow vehicles.

For what it’s worth, I’ve dragged a trailer the same size/weight as yours with two different vehicles, a 2.8 liter Jeep 4 cylinder and a 3.0 liter BMW 6 cylinder but both are turbo diesels, and both had no trouble climbing the 6-7% slope on I-70 west of Denver from 5,000 feet to 11,000 feet. It was the turbo that did it. No loss of power from sea level to at least 11,000 feet. 188 hp/335 ft-lbs for the Jeep, 265 hp/425 ft-lbs for the bimmer. Both topped the mountain in the 60-65 mph range, and could have gone faster if I’d been crazy enough to want to.

[Dennis12]

If your that stressed over mountains, stay home. Your not enjoying what you should be.

[PaulandAnn]

OK Thanks guys for all the encouraging feedback. The concensous is "rev it up". I know in my head a DOHC engine can handle the higher rpms. My other V8s have been pushrod LS1 and LS2 engines with torque down low.

Somehow my blood pressure seems to be linked to that tachometer when I get up past 4000!

And, I resist flooring the throttle. I DO have it in tow mode, but just shift manually before it does) But seriously, on those climbs I have to drop down into 2nd, get up to 5000 (redline starts at 6000), just to climb from 40mph back up to 50. Then I upshift back to 4th and 4000rpm, and it slows back down to 40. And this happens on the first hill, way before I've reached 7000ft.

I did check into turbos. What the heck, I put power adders on my Camaro (Cam, exhaust etc) why not this stock SUV??? Anyway Australia makes one for Armada/Titan but doesnt sell it abroad.

Thanks again, I'll try and chill at higher RPMs.

ps
A word about tow mode: Once I was cruising along in Drive at 60mph, on a long straight gentle rise. I looked down and the trans temp was nearly pegged. I down shifted manually and the temp dropped right down. So in tow mode by itself, evidently, I was cooking the torque converter.

[stevemorris]

we've had our ram hemi at full wide open throttle, 5000 rpm, 80 kph(50mph)a few times.
gear down, rev it up!
don't do it for hours at a time, watch the temp gauges, change the oil more often, it will take it!

[APT]

Was it 40mph at 3000rpm or at 5500rpm? Up hills and mountains, I expect you'll spend more time in the 4000-5000rpm range to maintain 60mph. Please use Tow/Hau mode, but you may want to manually override the gear as well if possible. That is what I di with my Suburban with similar powerband. The engines are designed to run there.

[jimh406]

Any power adder will help including tuner, air filter, and upgraded exhaust. I don't personally like keeping my gasoline engines near redline for an extended time. Your engine is starving for air at altitude.

Sure, you can go half the speed of other vehicles, but I suggest doing with the big slow tractor trailers for cover.