2017 Toyota Tacoma: Bilstein Shock Absorber Upgrade
by Dan Edmunds, Director of Vehicle Testing
Our late-spring trip to the Racetrack Playa in Death Valley had been gnawing at me. We built the trip around the idea of finding the limits of the Honda Ridgeline, but our 2016 Toyota Tacoma, which accompanied in a supporting role, became the focus after its rear shocks failed unexpectedly.
In the intervening months, I'd spoken with people with more miles logged on those Death Valley backroads than me. Few were terribly surprised about the Tacoma's performance en route to the Racetrack. If anything, the Ridgeline's comparative, and admittedly partial, victory surprised them more.
That particular road is notorious in the backcountry "overlanding" community precisely because its unrelenting washboard surface wreaks havoc on shock absorbers. The Toyota Tacoma TRD Off-Road is a popular truck among this group, and upgrading the dampers is one of the first upgrades on many owners' list.
I can totally see why.
The dinky 36 mm Bilstein shocks that Toyota fits to its off-road package are the smallest that the shock manufacturer makes. (The measurement refers to the diameter of the piston inside the shock absorber.) Hunt around in Bilstein's consumer catalog for a replacement shock and you won't find anything smaller than 46 mm.
I had a choice to make. I could take a minimal approach and go with Bilstein 46 mm replacement shocks all around, which would probably prevent a repeat of the same scenario. Or I could take a more definitive step forward and choose something bigger, more transformative, and better suited to more regular excursions in washboard terrain.
I chose to go big, which led me to Bilstein's 6112-series 60 mm aluminum-bodied front shocks. They include their own springs and height-adjustable perches that allow for preserving the standard front ride height or raising it as much as 1.5 inches in half-inch increments.
These are complemented by 5160-series 46 mm aluminum-bodied rear shocks with remote oil reservoirs and about a half-inch more stroke than the factory shocks. The extra travel would not alter ride height, but I figured it might improve suspension articulation somewhat.
This choice came at a price, however: right around $1,000. The more conservative 46 mm approach I dismissed would have cost $400. To offset the extra spend, I decided to install the shocks myself. I used the Rotary two-post lift in our shop, but set it at a height to simulate a floor jack and jack-stands. I wanted to see if this could be a driveway job.
I've removed and replaced first-generation Tacoma shocks many times, so I knew some tricks that might help. Here's how you can do it, too.
With the wheels off, undo the trio of 14 mm nuts holding the top of the coilover to the frame. Next, get a 19 mm socket and loosen the lower mounting bolt. The bolt probably won't come out until you lay a pry bar or long screwdriver atop the upper arm, insert the point between the coils of the spring, and then pull down gently while wiggling the bolt free.
But you can't get the coilover out at this point, even though it's unbolted. You first have to remove the stabilizer bar link from the knuckle, then disconnect the upper control arm ball joint by removing the spring clip and castellated mounting nut that binds it to the suspension knuckle. This joint won't automatically come apart after the nut is unscrewed, however, because the pieces are wedged together in a tapered hole.
You can use a puller to pop it loose, but I prefer a careful sideways blow with a ball peen hammer at the flat that's machined into the knuckle, right where the shaft is stuck in the tapered hole. Two or three moderate whacks are usually enough to break the bond.
When it comes apart, you need to grab the knuckle and hold it more or less upright, then zip-tie the loose upper end to something solid so it won't flop around and damage the brake line or CV boot while you're off doing other things. But the coilover assembly can't come out yet because the stabilizer bar isn't yet moved out of the way. To make that happen, you need to repeat the whole routine on the other side of the truck so that the stabilizer bar is free at both ends. Only then can it be rotated up and away.
With both upper arms loose, the stabilizer bar hinged up, and the knuckles loose, you can now try to remove the old spring/shock assemblies. It's a bit of a puzzle, but the general idea is to work the bottom end down below the lower control arm's forward edge while staying behind the steering arm, which does not need to be undone. The shock has no chance of coming out that way, but feeding it down through there allows the top edge to fully disengage from the frame and create the space necessary to rotate it backward. Rotate the top back far enough and you can then pull the whole thing up and out.
With both front shocks out, you'll need a spring compressor. The new 6112 shocks have their own springs and lower spring seats, but the upper spring seat and the nut that holds it all together need to be removed and reused.
Access to the right tools makes things go fast and stay safe. External strap-on spring compressors are unwieldy at best and dangerous at worst. I prefer a wall-mounted strut and spring compressor made by Branick. Take your parts to a shop for this one step. It's worth it. Luckily, I know two shop owners who have one of these.
The Branick makes it easy to take the old units apart, but before you start it's absolutely vital to take a picture or otherwise remember the relative orientation between the trio of upper mounting bolts and the axis of the lower mounting eye. You need to replicate this orientation accurately for the new shocks to fit.
After that's done, it's a simple matter of compressing the spring, removing the central nut, taking it all apart and prying the top mount assembly loose from the old spring.
Before the new shocks go together, you'll need to choose your ride height. This determines which of the six grooves to use when positioning the lower spring seat clips. I decided on 1 inch of lift, which would level the truck and improve front clearance but not make the rear end look weird at standard height. To do that, the 6112's instructions stated I should use the No. 4 groove on the driver's side and the No. 3 groove on the passenger side.
Tacomas are heavier on the driver's side, thanks to the offset of the fuel tank and the transfer case. It's also a slight nod to the solo driver, which is a statistically significant state of use. Most cars and trucks are like this, and manufacturers almost always install longer and/or stiffer springs on the heavy side. Bilstein supplies identical left and right springs to simplify matters, opting to make up the difference by offsetting the lower spring seats instead.
With the ride-height decision made, the units go back together quickly. It isn't hard to match the alignment of the upper and lower ends so they fit. I thanked my friend for the use of his spring compressor and headed back to our waiting truck.
The fatter 60 mm shocks are more finicky to install because of the extra bulk. Our job wasn't too bad, as my helper pulled up hard on the upper arm while I played Bilstein Tetris. After that it's a matter of bolting everything back together and using the torque wrench to make it all properly tight.
Removing the outer bolt of the upper arm while keeping all other suspension arm bolts tight provides a huge advantage: The installation does not alter the alignment, except for a symmetrical change in static camber due to the 1-inch lift. We can drive the Tacoma to an alignment shop when we're good and ready, but there's every chance we won't need to do it at all.
There's less going on in the rear, mainly because there are no springs to remove, no spring compressor to borrow. The main trick is knowing that the left and right ones are different. Don't get the part numbers screwed up.
The stock upper nuts on our units were hard to remove because of the way the lock nuts work; the shaft of the shock wants to turn and turn. There's a flat to prevent this by using a small wrench, but as the nut unscrews, the flat disappears into the rising nut. It disappears before the nut is loose enough to turn by hand. I could've made it easier by clamping a pair of vise grips onto the shaft of the old shock to prevent it from rotating, but that would've turned the old shocks into junk. I didn't want to do that, and so I struggled for a bit.
Once the upper nuts were off, I used a floor jack to release pressure while I removed the lower bolts. The old shocks were soon down and out.
The new shocks have sizable remote reservoirs, and I stared at the parts and the instructions for some time before starting. Ultimately, it's easy, and there's no need to drill mounting holes because Bilstein uses a pair of existing square frame holes to attach the brackets. Access to the bolts is tight, and the instructions advise applying a little locking compound to the threads. But it goes together easy enough, if a little slowly.
With the reservoir brackets in place, the shock installation is more straightforward and includes the usual new rubber bushings and spacers. The shocks themselves come strapped to hold them in a slightly compressed state to aid installation. I resisted the temptation to cut them off too early and make things harder on myself.
The lower end goes in first, and you might have to tap it into place or use a punch to help get the holes to line up. On the right side, I found it helpful to slip the remote reservoir into its bracket before I did this. On the left, I found it easier to secure the bottom end of the shock before positioning its reservoir.
The shocks are under extreme pressure, and the straps do not allow the washers and bushings to be slipped into place beforehand. I had a friend pull down on the shock with two hands to put slack in the strap. While he held it there, I cut it free and quickly slid the necessary washers and bushings over the shaft. He then moved it into position, let go and allowed the internal pressure to "grow" the shock into the mounting hole.
These rear shocks are inverted — another benefit to the more expensive upgrade. The original shocks, as well as Bilstein's more modest 46 mm shock upgrade, both use a traditional design with the shock body on the bottom and the shaft at the top. This makes the heavier "body end" move with the wheel, which makes it unsprung weight. Inverted shocks literally flip this the other way, with the heavier body end in a fixed position up top, with the slender shaft on the bottom in the unsprung weight position.
This difference also made it ridiculously easy to tighten the upper nut. I could simply grab onto the shock absorber body with one hand and hold it still while tightening the nut.
It all took about two-and-a-half hours, not including time spent driving to and from my buddy's shop or taking photos. The truck's new stance is not dramatically different and it looks nearly level, which to me is a just-right look.
In local driving, we've noticed that the ride over paved road is dramatically improved, especially in terms of body control. Yes, the overall feel is firmer, especially on jointed freeways, but the increased poise makes it worth it.
The Tacoma no longer jiggles after small ripples or quakes after sharp bumps. Body roll is more subdued, and it can now charge through deep dips at undiminished speed. Our truck's notorious brake dive has been reined in some, too.
I haven't yet taken the Tacoma back to Death Valley, but it's in the works. We're not expecting any surprises. With these larger shocks containing considerably more oil in which to distribute heat, and more surface area through which to expel it, I have little doubt the next trip to the Racetrack will be a comparative snoozefest.
Dan Edmunds, director of vehicle testing @ 37,686 miles