Off-Road.com's Land Cruiser Tech - Toyota Land Cruiser FJ60 Spring Over
|Spring over axle conversions are not new to the off-roading community. For years, spring overs have been the main way of achieving suspension lift for drivers of Toyota Land Cruiser FJ40s, Jeep CJs, International Scouts, and just recently, Suzuki Samurais.
Spring-overs, quite simply, move the previously below-the-axle mounted leaf springs to above the axle. This swap nets a generous amount of lift without sacrificing ride quality or the use of heavily arched (and sometimes stiff) leaf springs. In most cases, such as in the vehicle we feature here, the stock springs are used for their smooth ride and flexibility.
This article will focus on the steps that are involved in performing a spring over axle conversion (SOA) on a Toyota Land Cruiser FJ60 wagon. There seems to be a growing interest in spring overs on these large wagons yet not a lot of information exists on how it is done and what parts are involved.
Not only that, there is only a handful of sprung-over FJ60s rolling around out there. For our example, we chose to use the best parts possible and sought the knowledge of those that have done this type of conversion in the past.
Since there are no "how to" manuals or instructions for doing a spring over (for any vehicle), the task of performing the delicate work was done by All-Pro Off Road in Hemet, California.
Known for their experience in building trail worthy Toyota trucks, 4Runners, and Land Cruisers, All-Pro handled all of the welding and fabricating required to do the job right.
|Why a Spring Over?|
|Why lift a vehicle to begin with? To get larger tires under it, of course! Bigger is better, right? Seriously, lifting a truck is just one way to improve it's trail performance.
The bigger the tire, the greater the ground clearance. A spring over is just another way to get that desired tire size fitted to the truck.
On FJ60s, the largest practical tire that can be run when using an off-the-shelf spring lift is 33x12.50/15. While considered the absolute minimum for harder trails by some, 33" tires are a bit on the small side when one considers the weight of a fully-loaded Land Cruiser wagon.
Also, like we mentioned before, the larger the tire, the better the ground clearance. On a vehicle with as much rear overhang as an FJ60, ground clearance is at a premium to begin with. For the types of trails that the owner wishes to run, a spring over was the best choice when considering tire size, ground clearance, approach, and departure angles.
Aside from the amount of lift that a spring over yields (+/- 6" depending on the vehicle), utilizing this method of lifting allows the use of softer, flatter springs as the lift is not dependent on the arch of the spring pack. This leads to a supple highway ride and a flexy trail suspension. For our application, we used stock Toyota Land Cruiser FJ60 6-leaf spring packs front and rear.
An added benefit of of the spring over is that it easily allows flipping the spring u-bolts to where the threaded portion sticks up instead of down as in the stock form. Having the u-bolts point up prevents the threads from becoming damaged and creates more ground clearance by eliminating one more item from hanging below the axles.
|Before and after heights and ramp scores|
| RTI SCORE
|Fender Seam to wheel well|
There is no "grocery list" that exists as a guide for spring overs. Actually, not a lot of parts are needed to complete a swap like this one. However, it was decided early on that this project was going to be done correctly, the first time.
With that said, a basic parts list was made, citing not only safety concerns but also those that would enhance performance, both on and off road.