I tow a 5th wheel trailer and my GCWR goes about 20,000 lbs. I have a 350, V-10 (2valve) and 4.30 gears. I haven't had any trouble pulling in the Ozarks and Smokies. Also the lower portions of the Rockies, however, should I have to go up something like LaManga Pass in Southern Colorado (3-4 miles of 7-8% grade) I would like to know how it will react.
Does anyone here have that experience? I'm not trying to be the first one up the pass, just get up it without causing damage.
I would like to hear from the gasoline motor owners. I know full well all the diesel owner replies. I've seen them on this forum and on rv.net.

 

Just keep it at no more than half throttle and let the engine go up the hills at its own speed. Dont push it with that kind of weight and grade becase all your going to do is burn more gas and not get up there much faster

 

3-4 miles at full power is not going to hurt anything, if it is in good shape. Downshift and keep the revs up to reduce strain on the transmission. The engine can take it.

Jim

 

I pull with a EFI 460, slightly built, in my '88 F-250. GCW of about 16K to 24K. Here in the mountains of VA we don't have the altitude that yall do, but we have some very steep long grades. There is one pass up the interstate that is 7% grade, 7 miles long. I get a good run at it of about 75mph, put in down in third and hold it at about 4,500rpms all the way up. There’s one other hill that’s about a 6 mile hill, 9% grade, unfortunately you can't get a run at it because its a very winding road, I pull that hill in 2nd, about 45mph, 4,700rpms.

So in short, you probably don't have anything to worry about so long as everything is in good mechanical shape. I pull my truck absolutely as hard as possible when towing, with no ill effects except the dismal gas mileage.

 

I down shift before the engine lugs. Once the engine lugs it never catches up and you are stuck in low gear at really high RPM.

For example, my 94 F250 460 tows an 8000# trailer. If I downshift before it slows down I can pull at a steady 55 to 60mph in 3rd gear. If I let it lug and then downshift I get stuck at 45-maybe 55 in 2nd, screaming along. And then the upshift is really harsh. I usually let up on the gas just before the upshift to lessen then bang.

And of course engine brake versus ride your brakes, way too much excitement when the brakes fade.

Good Luck,

Jim Henderson

 

Actually full power is not full power at altitude anyway. Just watch the heat and keep it at about 3500 RPM or so (adjust throttle and gear selection as needed to keep it under 4000 and above 3000) to get the best effort out of your engine for amount of fuel consumed. If it get warm, slow down and gear down and you will make it fine.

 

Just kick the truck in neutral when going down the hills you don't need the engine retarding the trucks brakes should be plenty

Just kidding

Where I live we have 8-10% grades that are not straight they are twisty so decending them with out having your brakes on fire is a must.

The first thing you do before you leave is make sure the trailers brakes work you need them to work at max capacity. Your trucks brakes have to be in good shape and all 4 work. If you have rear drum brakes jack the truck up and manually adjust the rear brakes so they are just dragging. I bet you will find the back brakes will be out of adjustment those automatic adjusters don't do s***.

When decending a hill and you step on the brakes and it doesn't feel like its doing anything then your going to damn fast. You need to drop a gear and let the engine scream a little bit untill you get your speed down.

You use your gears to maintain your decent you use your brakes to prevent overrevving the engine. Once your brakes are hot they will just get hotter and become useless you need to let your brakes cool. If you can smell your brakes its too late they are already hot.

You decend a hill slowly and just say screw it to anybody that is behind you sure the speed limit says what it says but if your heavy take it slow.

With my trucks grossing 16,000-17,000lbs thats just the truck no trailers I never ever got my brakes hot enough that I couldn't put my hand on the hub and thats decending upto a 10% grade. Sometimes the hub is stone cold or just slightly warm. I drive my trucks like they have no brakes I try not to use the brakes unless I have to.

Climbing grades with a heavy load my speed has dropped down to 25mph thats just part of driving a truck you pull a grade slow. I will usually pull a 8% grade in 4th gear with my PSD grossing 15,000lbs my old IDI grossing 15,000lbs was the same or 3rd as the IDI had 5:13s and the PSD 4:63s and 5spds. I don't even bother revving the engine past 2000 on the diesels its pointless your not gaining any speed your just burning extra fuel.

If your constantly shifting from 4th to OD or 3-4 for guys with taller axle gears your just wasting time. Leave it in the gear the engine is pulling the best in and climb the hill. My old gas pot trucks I had the one with 351m grossing 14,000lbs on a 1 ton dually flatdeck I used to have to climb hills in 2nd gear and decend the 8%s in 2nd gear as the old 350s brakes were weak.

Another thing you had to watch out for is the transmission popping out of gear always have to keep your hand on the stick.

Steep hills don't scare me its the 14% grade driveways that people have here worry me as a loaded truck has real troubles stopping on them even with your brakes on the tires slide.

To sum it up take it slow especially if you are a newbie on hills if you can cook eggs on your brakes you know your traveling too fast. You need to get to a destination at a certain time leave yourself a extra hour or atleast 30 mins.

 

Thanks to everyone who has replied. The info has been good. If anyone else has experiences please post them.

 

I pull with the same truck and 2K more trailer with no problem in the mountains of Colorado I'm not sure where that pass is but I pull Berthhoud on US 40 and it tops out at 11300 ft. The best way I have found is to lock the tranny into gear, when it downshifts from 3rd to 2nd just lock it there and when it needs to go into low lock it into low or every time you let off the gas it will shift back up and hunt up and down. On the down side lock it into a lower gear there also and let the truck gain speed and them brake it hard and slow way down and them let off and let the speed build back up and brake again, that will allow the brakes so cool down. If you ride the brakes you will burn them out. Also make sure your controller is set up right so the truck is not trying to do all the braking.

Just take it slow and enjoy the scenery its a beautiful State.

Denny

 

Thanks RV puller. I've been waiting for you to post. I've seen your's in the past and felt you probably had the experience I was looking for.;

La Manga is in the South Central part on the Colo-NM Border between Antonito and Chama, NM. It's actually a two pass set up with LaManga on the North and Cumbres on the South. LaManga has the 7-8% grades for about 2-3 miles going up and down the north side.

 

I have towed conventional trailers over Red Mountain, Lizzard Head and Wolf Creek Pass in S.W. Colorado several times. What you have done in the past wouldn't even be a speed bump in comparison. In planning your trip, think about one thing only. BRAKES.

 

One thing I forgot you don't have to wind the you now what out of the motor, when I lock up in gear I very rarely run it over 3500 to 4000 rpm, and when I get all the way down into low I just run at about 20 to 25 mph and enjoy the ride. The one thing that I would like is a new TS tranny the closer gear spacing would work great in the mountains.

Denny

 

Okay, what were you towing with and how did it go? I presume it went just fine, but I'm interested in the details.

 

I live in AZ but go to S.W. Colorado every summer for some fishing, camping and general exploring around Dolores, Rico, Telluride, Ouray, Silverton and Durango. I pull a 26 TT with a 95 F-250 460 SRW.
My point was that this entire threads discussion has been about horsepower and how fast you can go up a grade and in what gear,etc. I can assure you that if you run into trouble it will not be going uphill, but downhill on those grades that seem to go on forever. There are plenty of curves and no guard rails. If you fell off in some places, they wouldn't find your bodies for a month. Just make sure your brakes and controler are properly adjusted, take your time, and enjoy.

P.S. Do not miss the ancient ones at Mesa Verde National Park. It was the New York City of the U.S. 1200 years ago.

 

Thanks daveee....
sounds like you've been up a lot of them.