calculating trailer height at angled approach

[MinnesotaDave]

Doesn't seem right somehow. I'd go for 1/10th of a foot, couple of inches +/- ??

No math, just WAG and closing my eyes and looking at the mental pic .

Yep, it's weird but the angle change is so slight it didn't do much.
Imagine a plumb bob on the top rear corner, then let it swing 2 degrees. Measurement wouldn't change much.

Here's the breakdown from 20-10 degree incline and 10-0 degree incline.

Y1 is incline
Y2 is height in feet

[Willie B]

Is the ramp in the same plane for the length of truck, and trailer? Truck being on a level plane lower than the inclined ramp would lower the hitch, raise the rear of the trailer. Do you own a bucket loader, or forklift? I used to use a bucket on a tractor to squeeze a motor boat into a barn with an inch of clearance. It worked very well, I could see everything. With a hitch clamped to your bucket you could raise the tongue to improve the height until the AC unit clears.

[LanceR]

This all seems like a lot of pole vaulting over a mouse turd. For crying out loud, just lay out the angle on the side of the trailer and put a tape measure on it.

[MinnesotaDave]

This all seems like a lot of pole vaulting over a mouse turd. For crying out loud, just lay out the angle on the side of the trailer and put a tape measure on it.

For a lot of people that is the fastest method.

For me, I can write the math faster than I can walk outside and get the tape measure

As a bonus, the math shows what angles won't work.

[LanceR]

Good morning, Dave

That is true about being able to check other angles. As I have an autocad program it could be done that way in a few minutes too.

As a longtime mechanized infantryman I did my share of route recon work and dealt with percentage of slope, approach and departure angles, overhead clearances at slope etc but that was a loooong time ago. When we built our last Morton building at our farm I had the front door made 14' tall and 24' wide. If it was road legal it was fitting in there and we didn't have to drop grain heads on a big combine.....

As another thought, if the slope isn't paved it is worth considering tapering it up a bit and having a flat apron at least as long at the distance from the rear of the trailer to the front of the front tire footprint. that way the trailer would be level backing in......

[MinnesotaDave]

Good morning, Dave

That is true about being able to check other angles. As I have an autocad program it could be done that way in a few minutes too.

As a longtime mechanized infantryman I did my share of route recon work and dealt with percentage of slope, approach and departure angles, overhead clearances at slope etc but that was a loooong time ago. When we built our last Morton building at our farm I had the front door made 14' tall and 24' wide. If it was road legal it was fitting in there and we didn't have to drop grain heads on a big combine.....

As another thought, if the slope isn't paved it is worth considering tapering it up a bit and having a flat apron at least as long at the distance from the rear of the trailer to the front of the front tire footprint. that way the trailer would be level backing in......

Sometimes I wish I knew how to work an autocad - maybe then I'd consider getting the program for it.

The screenshot was from my cell phone calculator. Pretty handy having that style calculator on it. I have the TI-89 and the TI-84 plus on mine.

[Willie B]

A level apron raises the trailer so it'd sit above where it does now. The truck would still be lower, so coupler is lower, rear of trailer is higher. My little camper with truck are combined at about 44 feet long. If Big has 44 feet of level, we can stop discussing this.

[bigb]

Truck is 21 feet with a turning radius of about 40 acres, trailers we are considering are in the 26 to 28 foot range ball to bumper. Approach is paved then driveway apron, about 38 feet to the street all about the same slope then the street which is basically flat. No tractor or fork lift here, I'm packed into my quarter acre city lot pretty tight. Will probably pick up an electric trailer dolly as it's quite a trick backing in on a blind curve with a traffic circle right in front of me, and the gates are at an angle to the street.

[Willie B]

Truck is 21 feet with a turning radius of about 40 acres, trailers we are considering are in the 26 to 28 foot range ball to bumper. Approach is paved then driveway apron, about 38 feet to the street all about the same slope then the street which is basically flat. No tractor or fork lift here, I'm packed into my quarter acre city lot pretty tight. Will probably pick up an electric trailer dolly as it's quite a trick backing in on a blind curve with a traffic circle right in front of me, and the gates are at an angle to the street.

Your world is foreign to me. I live on a street with 50 houses. There is one other street in a 38 square mile town with half as many houses. We have 3.2 miles of town road, four miles of state road, and 19 miles of road owned by the feds that lead nowhere. Our population is a bit over 200. Except for the Rainbow family of light gathering in 2016, encountering more than two people in a day is rare. Summer of 2016 residents were terrified!

[Willie B]

I'd spend time crawling before buying. Long trailers with light frames oscillate. Think of the Tacoma Narrows Bridge. A wave pattern starts, and grows in light framed trailers. 20 footers don't suffer much, 28 footers won't if frame is adequate. Tow that trailer before buying.

[bigb]

I'd spend time crawling before buying. Long trailers with light frames oscillate. Think of the Tacoma Narrows Bridge. A wave pattern starts, and grows in light framed trailers. 20 footers don't suffer much, 28 footers won't if frame is adequate. Tow that trailer before buying.

Same here. When I bought my first diesel pickup it was a hard to find used 83 F-250 with a T-19 4 speed, I was forced to buy from the local dealer after trying unsuccessfully to find a private seller of one. The salesman were inside the air conditioned showroom in their suits laughing as they watched me roll out a piece of carpet and lay underneath it.

Trailer we are looking at will most likely be a Grand Design.

[bigb]

Your world is foreign to me. I live on a street with 50 houses. There is one other street in a 38 square mile town with half as many houses. We have 3.2 miles of town road, four miles of state road, and 19 miles of road owned by the feds that lead nowhere. Our population is a bit over 200. Except for the Rainbow family of light gathering in 2016, encountering more than two people in a day is rare. Summer of 2016 residents were terrified!

I've been in your world. Spent a few summers up around Montpelier, in a place called Plainfield. I remember how beautiful it was, and how it rained most every day. (when you live in the desert you don't forget things like rain) I remember the Ben and Jerry's music festival in the White Mountains at some ski resort, saw many bands including the Fabulous Thunderbirds. I also remember we needed a fuel pump once for a Beetle and had to order it and wait two weeks. I remember one summer it was very hot for the locals, I had two SBC heads in the machine shop that were supposed to be ready Tuesday but since it was so hot they closed up and went home and I didn't get the heads for two more days. It's definitely a different world, one that I half way miss. One grows accustomed to having everything at your fingertips, all of the time. But the crowds I can do without.

[Willie B]

My friend who had lived in a number of places including New Jersey, was riding with me one day. I drove around the outskirts of Rutland VT. He looked at me, and said " You've just driven five miles to avoid a little traffic! You don't even know what traffic is! Try leaving home, 1/2 mile from home you think of another tool you need. It takes 40 minutes to get back through traffic to get it!"

[mwshaw]

Have you seen the hitch on a house trailer mover. The hitch has about a two foot adjustment hydraulic cylinder to handle this type of problem and grade crossing over railroad tracks. Something like that would make it work a lot easier for you on any trailer you put in there. It does require someone looking and doing it slowly to get it right.

[FernTJ]

Dave is correct, getting under the door will not be an issue. The door is only a problem if the driveway doesn't actually start it's slope right at the front of the garage. If it is more level for the first couple feet of driveway, then the door could become the problem.

If the driveway slope is as drawn then if you have a problem it will be inside the garage.

If it is 13 feet from the rear trailer axle to the rear of the trailer then when the rear wheel goes through the door the back of the trailer will be about 7 inches higher than when it levels out.

[tweake]

but some more accurate info would be handy.

what type of suspension does the trailer have, equalizing or non-equalizing?
whats the distance from the center between the axles and the rear of the van and distance between back wheel (where it touches the ground) and the rear of the van?

the highest point is going to be when the back wheel of the van reaches the crest of the hill (or the center bewteen the axle depending on suspension).
half the van length is say 156". 2" rise per 48" over 156" distance is 6.5" increase in height.
10'6" + 6.5" = 11'0.5".
so without accounting on angle its 0.5" to big.
however thats not accurate because its not 11' inside the garage. still need to factor in the actual height of the garage at ~156" inside.

as you can see you need a very accurate measurement of how long the van is from the wheels.

[Virgil5]

Just borrow the cat's laser toy and tape it on top of the trailer.