SAS, Solid Axle Swap, Straight Axle Swap — Same Job

Taking the independent front suspension out of a Toyota and putting a solid front axle under it. People call it an SAS, a solid axle swap or a straight axle conversion, and it is the single biggest change you can make to how one of these trucks works off-road: more articulation, stronger, simpler, and far easier to lift a long way without running out of geometry.

It is also a real project. Read the sections below before you buy anything — the kit is the smaller half of the job.

1985-1995 Pickup and 4Runner

The classic swap, and the one with the most support. These trucks came with a solid front axle until 1985, so the parts to put one back are largely factory geometry.

Leaf springs are the honest recommendation for a first swap. They locate the axle without any additional brackets, they are cheap to replace, and they do not require you to get link geometry right on your first attempt.

Tacoma

Later and harder, because nothing about the Tacoma chassis expects a solid axle. Two kit levels:

These fit the first-generation Tacoma primarily. If you are working on a second or third generation truck, talk to us first — parts exist and people have done it, but the amount of fabrication climbs with each generation and we would rather set the expectation before you have a truck on stands.

Link Suspension — 3-Link and 4-Link

If you want articulation beyond what leaves give you, a link front end is the next step. Our Trail-Link kits are the engineered version of a build people often do badly.

Brackets and links are available individually if you are fabricating: upper link axle bracket, lower link axle bracket, upper link frame bracket, lower link frame bracket, panhard frame bracket, panhard tubing, Trail-Link Four crossmember and the 20-degree lower link mount.

Steering

The part people underestimate. Moving the axle changes where the drag link has to go, and a swap with bad steering geometry is worse to drive than the IFS it replaced.

High steer is not a bolt-on preference, it is a geometry decision. If the drag link ends up at a steep angle you will get bump steer, and no amount of stiffer parts fixes it.

The Axle Itself — Knuckles, Hubs and Bearings

Most swapped axles come out of a truck that has been sitting. Budget for the rebuild, not just the swap.

Brakes

Early solid axles ran drums or small solid rotors. If you are keeping a 1979–1985 axle, the vented conversion is worth doing while it is apart.

Oil Pan Clearance — The Thing People Discover Too Late

A solid front axle sits where the factory oil pan wants to be. If you are swapping an axle under a 2RZ, 3RZ or 5VZ truck you will need a pan that clears it.

Order the pan with the kit. Finding out about it with the axle already under the truck is a bad afternoon.

Related

Axle and drivetrain parts by truck: 1989-1995 Pickup, 1990-1995 4Runner, 1996-2002 4Runner, 1995-2004 Tacoma and J70 Land Cruiser.

Building the engine at the same time? Start at Toyota engine platforms — if the truck is coming apart anyway, the labour overlaps.

Planning a swap? Tell us the truck, the axle you have or want, and how you intend to use it. This is the build where a ten-minute conversation saves the most money, because the wrong decision early costs fabrication later.

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