A 4th-gen 4Runner with a steel bumper, a winch and a loaded cargo area is a lot of weight on a front end built for stock. The nose sits low, dives on the brakes, and finds the bump stops on the first washout. Bilstein's heavy-load 6112 is the version built for that truck: stiffer springs and valving for 150-200 lbs of extra weight up front, the same 2.6-inch monotube and 60mm digressive piston, and circlip grooves to set the height with the weight on.

Heavy load means heavy load. Bilstein built this kit and its chart for 150-200 lbs of added weight up front: a steel bumper, a winch, armor. On a stock-weight front it rides stiff and sits taller than the chart. If yours is stock up front, the standard 6112 kit, 47-309975 is the right one.

What's in the Box

One front pair, as Bilstein boxes it. Everything comes loose, for you or your shop to put together:

• 2 Bilstein 6112 dampers. 2.6-inch zinc-plated monotube bodies with a 60mm digressive piston and a row of numbered circlip grooves. The circlip ships on the body; you move it to the groove you want.
• 2 Bilstein heavy-load coil springs.
• 2 billet aluminum spring seats. The seat sits on the circlip and carries the bottom of the spring.
• Top hardware: rod adapters, upper bushings, upper and lower washers, and new locknuts.
• Spacer washers for the top settings, used with the jounce bumpers.
• Not in the box: upper mounts. Bilstein's kit reuses your factory upper mounts and the rubber bushing glued under them. If the rubber is torn, collapsed or loose, replace the mount now, not after the job.

Setting Your Height

V8: same groove both sides. V6: driver side two grooves higher than passenger. Here's the order:

• Find your column on the chart (V8 4WD or V6 4WD).
• Driver side two grooves higher than passenger on the V6 only, where the chart shows a pair (for example #8 / #6). That offset is built into Bilstein's numbers to level the truck side to side.
• At the top settings, add Bilstein's spacer washers with the jounce bumpers, as the instructions show.
• Check the groove twice. One groove off on one side and the truck sits crooked. Count from the bottom groove (#1) on both bodies.
• Seat the circlip all the way into its groove. It should sit inside the spring seat and turn by hand. Bilstein warns that a half-seated circlip ruins the shock.
• Seat the spring seat on the circlip. The spring seat sits on the circlip and carries the Bilstein spring. It only goes on one way.
• Compress the spring safely. This is the step to respect: a coil spring under load stores a lot of energy. Use a mounted, shop-grade strut compressor. Don't use a rental clamshell compressor or anything you have to improvise. Any suspension shop with a mounted compressor does this step in minutes, so if you don't have one, let them.
• Reuse the factory upper mount and torque the locknut to 20 lb-ft (27 Nm). Hold the shaft with an 8mm wrench and use a torque wrench. Bilstein says it plainly: no impact wrench on the locknut.
• Mark driver and passenger before you install. Set each side to the chart, check it twice, and label it, so the truck doesn't lean.

Want it assembled? We don't list this heavy-load kit pre-built. Our assembled 6112 4Runner listing uses the standard kit, 47-309975, built to the height you choose. If your truck isn't carrying the weight full time, start there.

The V8 uses #1 to #5; don't use #6. The V6 uses four pairs, #3 / #1 to #6 / #4. Every setting lifts: V8 2.3" to 3.6", V6 2.1" to 3.1". The heights were measured with 150-200 lbs added up front; a lighter truck sits taller.

How to choose: Measure from the center of each wheel to the fender lip, front and rear, with the bumper, winch and gear on the truck. Pick the setting in your column closest to your rake plus the lift your rear coils add. Stuck between two? Call us with your measurements and build list: (213) 433-3616.

Matching the Rear: Bilstein 5100 or 5160?

The 4Runner runs coil springs on four links, so the coils (or a spacer) set rear height and the shock only needs the right length. Plan the rear coils first.

Bilstein 5100 (33-313146) or 5160 (25-311211 left, 25-325096 right). The 5100 covers stock height to 2" of rear lift. The 5160's remote reservoir adds oil, so it runs cooler under a loaded cargo area or on long washboard roads. On a truck heavy enough to need this front, the 5160 is usually the pick.

Run the 5100 if

• Your rear coils lift the truck 2" or less
• The weight is mostly up front (bumper, winch)

Run the 5160 if

• The back carries real weight: drawers, a fridge, a rooftop tent, recovery gear, a trailer
• You run long stretches of washboard or desert road, where a shock without a reservoir gets hot

When you need something else: More than about 2" of rear lift needs a longer shock. A 4Runner with X-REAS or rear air needs a plan first. Call us: (213) 433-3616.

5100 Rear Pair, 2003-2009 4Runner 5160 Rear Pair, 2003-2009 4Runner

On the Road

With the weight on, the front stops sitting nose-low and diving under braking, and settles in one motion after a dip. Without the weight, it rides stiff and sits tall. That's the trade for a kit built for a loaded truck.

Off the Road

The heavy-load springs keep the front off the bump stops with a bumper and winch out front, and the 2.6-inch body holds its damping on long washboard roads. The top settings cost angle at the upper control arms and CV axles.

The Honest Trade-Offs

• You need a compressor or a shop. The kit arrives as parts. Budget for a shop to put it together if you don't own a mounted strut compressor.
• Not for a stock-weight truck. Bilstein built it for 150-200 lbs added up front. Without the weight it rides stiff and sits taller than the chart.
• No factory-height setting. V8 starts at 2.3", V6 at 2.1".
• Changing height later means doing it again. The circlip sits under a compressed spring, so a new setting means pulling the coilovers and using the compressor again. Measure before you set it.
• The top settings need supporting parts. From about 2.5" up, aftermarket upper control arms bring camber back and keep the ball joints happy.
• Don't stack a spacer on top. A strut spacer on top of a 6112 pushes the front past what the factory arms and axles are built for.

Install Notes

• Fits 2003-2009 Toyota 4Runner 4WD, V6 and V8.
• Built for a heavy front end: steel bumper, winch, armor.
• 2WD 4Runner: not on Bilstein's heavy-load chart. Call us.
• X-REAS or rear air suspension: call us before ordering. Some 4Runner Sport and Limited trucks and many GX models came with X-REAS cross-linked shocks or rear height-control air springs, and the rear plan changes.
• Spring compressor or shop required. Use a mounted, shop-grade compressor. A suspension shop builds the pair in minutes.
• Reuse your factory upper mounts (with the rubber bushing glued underneath). Bilstein doesn't include them.
• Torque the locknut to 20 lb-ft (27 Nm). No impact wrench.
• Stock-weight truck? Use the standard kit, 47-309975. A 2010-2024 4Runner uses 47-310025 (standard) or 47-311039 (heavy load).
• Removing a strut spacer? Leave it off.
• Get an alignment right after install. Any lift changes camber and toe.
• Recheck the front height after the springs settle in over the first few hundred miles.

Who Should Buy These

4th-gen 4Runner owners whose trucks are built and carry it every day: bumper and winch up front, gear in the back. If yours is stock or close, the standard 47-309975 kit rides better.