Not quite, 100% grade would be 45 degrees, or a 1 to 1 pitch.

 

Think of a right triangle. If the two short sides are equal in lenght to each other it is a 45 degree long side but is a 100 per cent grade.

 

I drove on an 11% grade in Alaska going up until jasper national park and I saw some 16% grades in California... going from Sacremento to Mammoth Mountain I think? I had taken a picture of it but lost that too.

 

The monarch pass in Gunnison Colorado is by far the steepest pass I everseen, topping out about 12000. 70 degress on the bottom snow at top

 

Good one.

 

monarch is a big tall pass but i find the drive up 550 from durango to silerton to be much more exciting. went up one year with a 85 chevy 454 [carbed]powered motor home. had the wife and my 3 kids and my buddie jai bird and his son. behind us we had a 24' wells cargo trailer with my land cruiser on 38s backed in and we drove his zuk on the hood of the land cruiser to get us enough room. then we loaded up all the spare axles we had and parts. plus the air compressor, floor jacks impacts and most of our tools. we blew tires like there was no tommorow, but that climb out of durango was the slowest thing i have ever done. we hit it at about 2 in the morning. by the time i made it to the first pass we were down to 3 mph and my leg was killing me from holding the gas peddal down so hard.

 

Monarch pass is 11,300 feet and pretty steep.

gunracer1,

You must be talking about Red Mountain Pass between Silverton and Ouray, CO on Hwy 550. That's one of the steeper passes in CO. It tops out at 11,100 feet I believe, and drops fast on both sides. Another pretty steep road would be Hwy 65 going up the north side of the Grand Mesa to Cedaredge. Don't know the grades on either of those. Don't remember seeing them marked. There are lots of steep roads here in the Rockies. Once you get off the major highways, 10% grades are common although they usually aren't very long.

Possibly the scariest paved highway I can think of would be Independence Pass between Aspen and Leadville. Tops out at about 12,100 feet. It's only open in the summer because of the horrific weather up there. It has major drop offs on the side with no guard rails. I don't think it's quite as steep as some of the others, but it is the most frightening visually. Never even thought of towing anything over it.

I've lived all my life within 15 miles of the Rocky Mountains. We do the vast majority of our towing there because that's where we camp. I don't really know what it's like to tow on flat straight roads.

 

Killer: Going down the south-side of Monteagle would be real scary,beause you would be in the Tennessee river ater flying thru- the wild blue yonder for a minute or so,I-24 runs East and west,you probably meant the East side of the hill going toward Chattanooga.,Many a trucker met his fate on the east side of monteagle,before they built the new road. Rookie drivers and flat land drivers would tend to under-estimate how bad it was,because its not a long hill.