Your car’s broken. Again. What’re you going to tell your spouse/companion/parents!? More important than that, how are you going to get home? How about another scenario, you’re trying to get your car to the track, but she isn’t exactly road-legal.. Now what? Well, you’re going to have to get your car on a trailer! I can already hear some of you telling me how your car is lowered, and it’d never go on a trailer. Well, I got mine on a U-haul trailer, and had 3″ of ground clearance.. three feet in front of the wheels!
Loading a low car onto a trailer isn’t a matter of brute force, but of leverage. And lumber. Lots and lots of lumber. I’d recommend using 2×6 at least, even wider lumber is much safer. Using some math, and a very gradual incline, nearly any car can get up onto a trailer.
I can hear you guys groaning when I mentioned “math”, but it really isn’t that bad. I’ll walk you through the calculations, and how to ensure you won’t damage your car while loading it.
Looking For The Quick Version? Maybe You Prefer YouTube? Here!
Taking Measurements Of Your Vehicle
Our first step in getting your car safely on a trailer is to know more about your car. For that, we’ll need to have seven measurements:
- Center of front wheel to tip of front bumper
- Center of rear wheel to rip of rear bumper
- Height of tip of front bumper
- Height of tip of rear bumper
- Length of your car from tip to tail
- Height of side skirts in the center of your wheelbase
- Distance between the centers of front tires
Now, I’ll walk you through how to take each of these measurements. Some are very simple, others a little trickier, so I’ll explain how to take them all without any assistance.
Center of front wheel to tip of front bumper
This measurement is so we know how much of an angle your vehicle can climb without scraping the front bumper. For this, we’ll be simulating the 2×6 lumber that your tire will be hitting. Taking the metal tip of the tape measure, wedge that piece right where the tire hits the ground. This will simulate the thickness of a piece of wood. Then, just stretch the tape measure out straight forwards from the wheel. Once you’ve stretched out a bit past the bumper, pick up your end of the tape measure. Stop once the tape measure hits any piece of your car, and that will be your limiting factor. Set the tape measure back down, and measure the distance to that piece of your car.
Height of tip of front bumper
Now, the point your tape measure hit, we need to find out how high that is. If you can, remember which piece that is, and use the tape measure to find the height. If you can’t remember, then grab a second tape measure. Hold the first in place, then use the second to measure the height of your contact point.
Center of rear wheel to tip of rear bumper
This process is simply a reverse of measuring the front bumper. Wedge the end of the tape measure behind your rear wheel, extend it out, and lift. Keep in mind that this may be your exhaust! We’re looking for the furthest back point on your car, not exclusively the bumper. Even if your tape measure misses your exhaust entirely, you’ll have to keep in mind that your ramps or the ground could still contact it.
Height of tip of rear bumper
Now, whatever piece of your car was the contact point, do the same as the front bumper. Get the height of your contact point, and then we’ll be done with the bumpers.
Center of side skirts height
Sometimes, the clearance of your car’s bumpers isn’t the limiting factor. You may bottom out on the edge of your trailer. To get a rough idea of your clearance, we’ll start by measuring between your wheels, length-ways. Then, divide the length by two, and get the height at your half-way point. That’s your most likely point to bottom out on most cars and trailers.
Length of car from tip to tail
This one is a little trickier to measure, but is still important. You’ll need the contact points you found in steps one and three, and a long tape measure for this. To start, feed the tape measure under the front of your car until the end is sticking out under the rear bumper. Now, lock your tape measure, grab a brick (or something that heavy), and go to the rear bumper. Line up the end of your tape measure with the contact point from earlier, and use the brick to hold the tape measure in place. Next, go back to the front, and take down the measurement from your front contact point. Make sure this is as close to accurate as possible, as we’ll be using this primarily.
Distance between centers of tires
We can cheat a little with this measurement, since odds are you’re running the same tires on your front left as your front right. So, what we’re gonna do is go to the passenger front tire, and start feeding the tape measure through to the driver’s side. Lock the tape measure, and head to the driver’s side. Align the end of the tape measure so it’s touching the *inside wall* of your driver’s side tire. Hold it there with a brick or something similar, then head back to the passenger side. Now, take down the measurement to the *outside wall* of this tire. Since you’re running the same tires on both sides, that’s the distance between the centers of your tires, and will be our ramp spacing.
Taking Measurements Of Your Trailer
We’ve got all the dimensions we’ll need from your car, but we still need to know more about your trailer. If you’re looking at this, I presume you’ve already got a trailer your car will fit on when all is said and done. We still have to plan out our ramping, however. For this, we’re only going to need three measurements:
- Thickness of your trailer’s included ramps
- Length of your trailer’s included ramps
- Deck height of rear tip of trailer
As was the same with measuring your car, getting accurate numbers will ensure you can have accurate math towards your ramps.
Thickness of your trailer’s included ramps
While the angle of your ramps is most important, we have to start here. Even if we had a one degree angle, if your ramps are taller than your ground clearance, we’re up a creek without a paddle! How to measure this is fairly simple, just measure at the point where your ramp contacts the ground, from the bottom to the top of the ramp. Unless you have custom ramps, or are very lucky, they’ll probably be thicker than an inch and a half. We can make up the difference with various lengths of wood.
Length of your trailer’s included ramps
Now that we have the thickness of your ramps, we can worry about their length. If possible, completely remove the ramps from the trailer and lay them on the ground. Then measure the ramps, from tip to tail. If you can’t take them all the way out, then just pull them to their deployed position, and measure from the bed of the trailer to the far end of the ramp. Once we know the length of ramp you already have, we can decide how much extra we’ll need.
Deck height of rear tip of trailer
We need to know how high your car needs to go in order to do our math. Going from the surface the car will be sitting on, measure to the ground with the trailer hooked to the tow vehicle! We’ll need to have measurements for the time you’re loading the vehicle. If we know the rear edge of your trailer’s height, we’ll know the vertical part of the triangle we need to make (more on that in a bit).
Now, Onto The Math Portion
Now that we’ve got the measurements for your car and trailer, let’s put them together and plan out your ramps. We’ll use my ’91 Silvia as an example. From the front tire to the front bumper was three feet, and the contact point was three inches off the ground. If we simplify the equation (3 feet equals 3 inches, divide by 3, we get 1 foot equals 1 inch), we can increase our angle by one inch for every one linear foot the wheel travels. Since we’re using longer boards, we won’t worry about making a perfect exponentially curved ramp, we’ll just use two inclines.
For my first incline, I can only go up one inch per foot. So, if I’m using 2x6x8 boards, I can go up a total of eight inches by the end of the board. With a trailer height of ~20″, this is not a problem. Seeing as my entire wheelbase will be on the first board before I hit my ramps, I can afford to increase the angle to two inches for every linear foot. With the ramps I have with my trailer, this will work.
Lifting The Ramps To The Proper Height
Now we just need to figure out how to get the ramp surfaces to those specific heights. Since we’re looking to get an 8″ height, we can subtract the thickness of our ramp (2″), and make up the difference with some square lumber (6×6). From there, I’d measure the distance from the ground to your ramp surface, and if it isn’t quite 8″ (some wood isn’t the size it’s advertised as!), shim it with some 1x lumber.
I’d recommend making some supports for your ramps, instead of just trusting the integrity of the lumber. At the half-way point in your ramp, I’d put a 4×4 block of wood, just for safety measures. I’d rather pay for a bit more lumber than a new front clip for the car!
Another thing you ought to note is the initial jump onto your ramps. The thickness of the 2×6 lumber we’re using matters, as you’d have to subtract that from your maximum angle. Luckily, the solution is easy. Get another piece of lumber that’s just over the length from your tire to the front of your bumper, and lay that flat on the ground in front of your ramps. That’ll raise your starting position, and negate the thickness of the wood in your calculations.
Getting Lumber and Test Fitting
Now that we know how much lumber you’ll need, it’s time to fetch it. I personally go to Menards, but there are many different options. If you don’t have a means to carry the lumber you’re buying, I know most Menards locations offer rental trucks for near $20/hour. The price can add up, but in a pinch, they’re incredibly helpful. Ideally, all this lumber will be stored inside, not exposed to the elements. If that’s the case, then untreated lumber should do just fine. If you don’t have space indoors do store the lumber, however, you’ll need to buy treated lumber so it retains its strength when exposed to the elements. Still try to keep it somewhat covered, however, as every little bit helps.
While you’re making your purchases, you’ll need to get your ramping materials, but that’s not all. You should also get a board that’s the length of your car, from front contact point to rear contact point. Also, get two boards that are just over the height of your clearance front and rear, to simulate your wheels. I’ll explain what to do with these in just a bit. Remember you’ll need spacers and reinforcements underneath the ramps as well, in the form of 2×2, 4×4, or 6×6 blocks.
Simulating Your Vehicle With Wood
Now, with that long piece of lumber you got for simulating your car, we’re going to attach the two small spare pieces you got. First, decide which part of the board is the front and which is the rear of your vehicle. Then, mark where your “wheels” will be attached, using the real measurements we took earlier. Whether you screw the wood together or just use clamps is up to you, but the next step is to attach those wheels. Make sure your ends are the correct height off the ground and affix the pieces of wood to your board. We’ll be running this across your ramps to ensure your setup won’t damage your vehicle or get hung up in any way.
Once everything is tightened down nice and snug, let’s set up your ramps. Using the math we did before, you should know what lumber goes where, and have all your blocking material by this point. Set up the ramps you made, and then, grab that car template we just made. Nearly dragging it on the ground, run that piece up each of your ramps. If either tip of the lumber, or the bit in the center, touches the ramps, you’re going to scrape. If it’s a minor nudge, you won’t have to worry too much, but any significant contact could displace your ramps and possibly knock them over.
Finalizing Your Setup And Packing It For Your Trips
Once you know your ramps are safe for your car, take some pictures of your setup. This will help you re-construct them at later dates, already knowing you won’t have issues with clearance. If there are some parts that you can easily leave attached, such as the blocking and reinforcements under your ramps, this will make assembly even easier. I’d recommend drilling holes through your ramps where your supports sit in order to screw together when it comes time to drive up them. While that isn’t strictly necessary, it’s an easy step that increases the safety of the setup drastically.
You aren’t only going to need your ramps to put the car on the trailer, you’ll need them to take the car off as well! That means we’ll need to bring all that lumber with us, without it being in the way of our car. This is why I recommended just drilling the holes for screws, and not actually screwing the ramps together at home. While there’s plenty of room for your ramps on the trailer without the car, you’re going to need to haul those ramps and the car simultaneously. For my 240, I was able to store the lumber to the side of the car on the trailer, and some steel ramps underneath the trailer just in case. The 1991 240sx was never a wide car, so even with the wheel spacers, I still had plenty of room to the side of the car for lumber.
Final Step, Let’s Load Your Car On To The Trailer! (Yeah, I Guess We’ll Unload It Too)
For the loading process, I’d recommend using a winch, come-along, or some other external propulsion source. While your car may be more than fit to drive up the ramps, there’s no guarantee your rear wheels won’t just kick the ramps out from under itself. If you’re completely set on driving your car up the ramps, however, you could find a way to affix the ramps to the trailer to circumvent the issue entirely.
However, for the winch/come-along route, you’ll just need a reliable tow point, and either a wireless winch remote, a friend, or a TON of time. You’ll need to be constantly steering the car, making sure you won’t hit the trailer or fall off the ramps, and pulling the car up the trailer. If you already have the car lined up with the trailer and your ramps, you could steer the car, then take the key out of the ignition (locking the steering column), then focus on pulling it up. If the car starts to veer off, then stop pulling it up, put the key back in, and adjust the steering again before locking it. With enough time and small adjustments, your car should come up on the trailer easily.
Once you’re up on the trailer, you’ve gotta tie it down REALLY WELL! The U-haul trailer I rented provided me with chains to go around the axles and a net-like set of straps to lock the rear wheels in place. Even if you don’t have those net straps, using chains around the axles is a very bright idea. Also, using heavy-duty ratchet straps to fix the car in place helps. Once your car is completely secure, set the e-brake (or put the car in 2nd gear), as a last-ditch safety effort.
Unloading Your Vehicle
Unloading is so much more simple than loading. Set up your ramps, make sure they’re properly aligned, and remove all your straps and chains (leaving the handbrake or shifter engaged to hold the car). Then just hop in, turn it on, and slowly drive off the ramps. Since gravity is doing most of the work, you don’t have to worry about spitting the ramps out. It’s that easy! If you can’t open the door to your car while it’s on the trailer, I’d recommend leaving a window down so you can Dukes of Hazzard your way in.
And there you have it! Loading and unloading your lowered car onto a car hauler, using only your brain, a tape measure, some wood, and a winch. Click the link if you want to watch my overview of this topic on YouTube.