Updated:
Every guy that’s ever worked on a car has had the uh-oh moment when they realized that the floor jack they brought for the job at hand was not big enough or doesn’t lift high enough. It’s a frustrating and humbling situation, I know.
The first, and natural, reaction is to publicly recite all of the swear words we’ve ever learned from 3rd grade through adulthood. The second, and more productive, reaction is to begin scouring the garage floor looking for something solid enough to use as a wedge between the floor jack saddle and the frame or other jack point of the vehicle.
No matter when or where this issue arises, the solution always ends up the same; a block of metal or a block of wood. This is a dangerous prospect that is not to be taken lightly, but is often unavoidable.
The good news is that there are a variety of engineered floor jack extension products that take a good deal of the danger out of this process. With enough ingenuity, it’s even possible to build a purpose built jack saddle extension yourself.
A necessary disclaimer to this topic is that floor jacks are meant for lifting and lowering, not holding. You should always utilize quality jack stands for any project involving any part of your body being beneath the vehicle for any significant amount of time. Once you’ve got that covered, it’s important to evaluate the situation. Is the problem that the jack travel is not enough, or is the jack just not have sufficient capacity?
For example, if you want to lift a Ram 3500 with a 1 ton floor jack, you don’t need an extension, you need a bigger jack. When dealing with lifted vehicles or other vehicles with a lot of suspension travel, you will almost certainly need some type of jack extension in order to safely raise the vehicle. Some jacks made for trucks and SUVs do exist but often, the max lift height is still not enough.
Many floor jack extensions utilize a keyed base or a captive spindle and socket design which allows the extension to sit atop the jack saddle securely before any pressure is applied. Some models also have a machined channel or slot designed to be positioned on either side of a frame seam weld.
In all instances, the vehicle contact surface of the jack extension should be at minimum, the same size if not larger than the primary jack plate or saddle to ensure stability when lifting. The same is true for the jack saddle contact surface of the extension. This will help to prevent any unbalanced distribution of load from the jack to the vehicle.
Whether using an engineered manufactured jack extension or an improvised one-off model, it is vitally important that the extension is able to remain positioned and in place while the jack is being maneuvered. This is especially important with improvised jack extensions. If the saddle extension moves or is nudged off-center, the load may no longer be centered on the jack saddle or the extension saddle, which is not a good scenario to be in.
Once the jack is positioned beneath the jack point, the jack saddle should be raised steadily in order to confirm the alignment of the floor jack extension with the jack point. Once the floor jack and extension begin to compress under load, it is important to visually verify that the floor jack is applying load vertically without too much horizontal loading. Excessive horizontal loads could lead to slipping of the vehicle on the jack; especially with an extension in place.
The initial loading of the floor jack extension is also a good time to verify that the wheels of the vehicle are chocked or otherwise secured. Once this has been confirmed, you should be all clear to proceed with lifting the vehicle as usual. Again, once the vehicle has been raised a desired height, put the jack stands in place and release the load from the jack slowly.
Lowering a vehicle with a floor jack extension is a reversal of the same procedures. There is some underlying danger involved when using saddle extensions, but a little advance planning and careful execution can make the process painless.