How steep is too steep?

[Tin Diesel]

We have an opportunity to boondock this summer in a fabulous place in Colorado. Access is via a driveway that is 900' long. There are a couple of 100' intervals on this driveway that have a grade of 15-18% (maybe as much as 20%). No issues with turn radius or anything.

We have a 30' Classic (1999) towed by a 4x4 Ford F250 Diesel. We can go up/down as slowly as we want.

Questions:
1. assuming good road surface, any issues with this combination getting up a grade this steep? (the road is packed gravel, not asphalt, but its brand new)
2. any concerns about gray/black/fresh water tanks? Should they be emptied before going up/down? This is not just a weight issue - we don't want black water spilling out from the toilet seal!!!!

Thanks.

Here's our rig, and our destination!!!

[Bob Thompson]

Having traveled on some roads with slopes in the range you describe, traction will be your most critical issue. The worse condition would be loose gravel. If surfaces are firm and tight, no problems.

[CanoeStream]

Do you have Enkay Rock Tamers mounted on your hitch to cut down throwing gravel? They're a good idea for all around use.

[Over59]

Cann't imagine you don't have the power if your traction hold.

I am wondering in such a situation which would give you more tractions.
1) No WD, let the full weight go to the rear wheels and use 2 wheel drive.
or
2) WD with 4 wheel drive.

How is your truck setup. If one of the rear wheels spins are you dead in the water or will the other still have traction?

[thecatsandi]

Loss of traction would be a big problem. If the truck slides you may not be able to stop. going backwards. I would try the truck only first.

Do you have limited slip rear end?

[Silvertwinkie]

Give 'er hell and keep the 4wd on.

Ditto the mudflap comments....

I think you'd be fine. Loose gravel, ok, as long as you don't loose momentum. It's not the safest thing to do, but going by the photos, it doesn't look **that** bad....then again, looks can be deceiving.....

[Tin Diesel]

we have limited slip, and have already been up the driveway in the contractor's F250. Even a 2-wheel drive would be fine without a trailer. We're just worried about 'spilling' stuff and whether this is just too steep. I know the Ford has the power!

Oh yeah - yes we have Enkay's.

[Goin camping]

4Wd at a slowish constant speed and you're there. Don't stop until you reach the top.

Airstreams handle really well off pavement. Even in deep sand. So don't worry.

[pmclemore]

With a good surface, I wouldn't worry about going up.

Going down, however, may just scare the bejeesus out of you.

[garry]

20% grade is "very" steep.
Compare highway grades at 6 to 8% and they can be tough to pull a heavy trailer up and on the down side they have run outs for runaway trucks.
I doubt 2 wheel drive would climb a 20 deg slope unless paved.

Garry

[Lumatic]

Others have touched on my thoughts:
1. On the uphill don't stop or you could find yourself in the position of not being able to go up and loosing control on the way down backwards.
2. On the way down you will have the trailer pushing you and you could loose control. Go as slow as possible.
3. This may be overkill but I guess you could rig a block and tackle or use wheel blocks for the way down. Are you a sailor, got a spare anchor?

[Tin Diesel]

I should have mentioned that construction trucks will use this road, and it was designed accordingly (big dump trucks, concrete trucks, etc.).

I should have refined my question more, but I think our biggest concern is simply the concept of 'tilting' the trailer that much. Sounds like we'll be OK.

[Bob Thompson]

Once, my wife failed to turn the shower off at the faucet, which left a trickle at the shower head which she had turned off. We were hooked up to city water and the shower head trickled all night. In the morning, we had 2" of water standing in the shower. Aargh! Luckily, the dump station was about 50 yards away on a level road. It was a nice slow drive to it. It would have been disastrous to drive up or down any grade to get to a dump station.

[Aerowood]

Another thing I would really watch is the weather. The weather here in the high country can change dramacticly from morning to evening. A road that was passable in the morning can turn into a nightmare with a little rain or snow mixed in. Alot of roads in the Colorado Mountains turn into creeks with very little rain. Be prepared to wait it out and let the roads dry before proceeding to your next distination.

[Foureagles]

Over59 touched on the WD hitch issue, and this is one often overlooked in rough terrain. Negotiating a steep dip with a long trailer can cause the WD to lift the vehicle's wheels right off the surface, and less extreme articulation can certainly lessen rear traction.