Maintenance › The 2.5 Boxer › FB25 / EJ25 › Field report

$772 to Change Four Spark Plugs — on a Car My Father Helped Build

He wasn't gouging me. Every guide and every forum thread on this job opens the same way: get underneath, pull the motor mount nuts, jack the engine up off its own mounts. Here's the four months I spent finding out why — and what a man who'd worked my dad's line handed me on a tailgate in Pennsylvania.

I'm not a mechanic and I'm not selling anything. I shoot documentaries by myself, which mostly means I drive.

Madison County distilleries. Fiber farms up in Yancey. Apple orchards around Hendersonville, the Parkway when the light's right, and about four times a year a straight run up I-77 with everything I own in the trunk. That car is my office, my grip truck, and the reason I get paid.

My father spent thirty-one years at Subaru of Indiana, in Lafayette. Outbacks and Legacys. He retired in March of 2020 and he was gone by that winter, and the last thing he ever gave me was a note in the glovebox of a car he'd had a hand in.

Built it. Drive it well.

So when it came time to do the plugs, there was never a question about who was doing them.

That's the part that still gets me. Not that I couldn't figure it out. I knew exactly what needed to happen by the end of the first evening.

I just could not get a tool on it.

If you've never had the hood up on one of these, here's the whole problem in one paragraph.

A boxer engine lies flat. That's the entire point of it — low center of gravity, the reason the car holds a wet road the way it does, the reason we all bought them. But lying flat means the heads don't face the sky. They face sideways, out toward the frame rails. And a spark plug goes into the head at a right angle to the head.

Which means your plugs don't live on top of the engine where a socket drops straight down onto them. They live out on the sides, pointed directly at structural steel, in a slot about as wide as your three middle fingers.

The front two, you can win. Everybody wins the front two.

The one on the driver's side, in the back, is a different animal. On some of these cars the gap between the coil and the frame rail is shorter than the rubber boot on the coil, so you have to rotate the coil most of a turn just to snake it out past the steel. And once the coil's out, you're looking down a hole at a plug you can see, that you can put a fingertip on, with nowhere on God's earth to put a ratchet.

Go read the forums. There's a thread on the Outback board titled "Really?? Engine removal for spark plugs?" and it isn't a joke thread. A man on the Forester board writes: "It is still worth the effort to get under the vehicle, remove the 2 motor mount nuts and then jack up one side of the engine — change the plugs — then jack up the other side." Another one, on the Outback board, after four hours: "Joint sockets don't work as there is not enough clearance." The DIY guides say the same. Locate your motor mounts. Remove both nuts.

That is the accepted answer to a maintenance item on the sticker in your door jamb. Unbolt the engine from the car.

You don't have to pull the motor. But the reason grown men keep saying you should is real, and it isn't that they're soft.

I went at it the way everybody goes at it, in about the same order.

Spark plug socket and a short extension. Went in fine. Couldn't get a ratchet on the end of it, because the end of it was three inches from the frame rail.

Long extension and a universal joint. This is the one everybody reaches for and it's the one that taught me the most. The u-joint deflected the second I put weight on it and walked off the plug. And here's the thing about a u-joint working at an angle: it doesn't even turn evenly. The output speeds up and slows down twice a revolution, so what's on the other end takes a pulsing load instead of a steady one. It never broke loose. It just slapped.

Wobble extension. Better. Still tilted. And a socket that goes on tilted isn't sitting on six flats anymore, it's pressing on two corners, and the corners are the thinnest metal on the thing.

Stubby ratchet, by feel, one arm down the back of the engine with my cheek against the strut tower. Three degrees of swing. Three degrees on a plug that's been in an aluminum head for nine years is the same as zero degrees. An hour of that and my knuckles were open in two places and the plug hadn't turned.

Somewhere in there I went looking to see whether it was just me. It is not just me. A man named Rob Evoy up in Brutus, Michigan, wrote down his own version of this list in one sentence: "tried snubnose ratchet, long thin ratchet, no joy, dealer quoted 814.52."

Four tools and a number. Same afternoon I'd just had.

Here's what I only worked out later, and it's the whole story.

Every one of those tools puts a bend somewhere in the path between your hand and the plug. And the second there's a bend, the load stops going where the strength is.

It wasn't my hands. It was the shape of everything in my box.

So I did what you do. I called Prestige, over in Asheville. Not to book it — to hear the number.

Seven hundred seventy-two dollars and eighteen cents. Four spark plugs. He read it out the way you'd read out the weather, and then he told me he could fit me in three weeks Tuesday.

He wasn't trying it on. That's what the job pays in the book, and the book pays it because of the access, not because of the plugs. He was being straight with me. He just happened to be describing a week's pay for a maintenance item that on my dad's old pickup was forty-five minutes and a cup of coffee.

And I've paid shop bills my whole life. I'll pay them again. But there is a difference between paying a man for skill I don't have and paying him for room I don't have, and that one sat wrong.

Then I did the rest of the arithmetic, the part nobody itemizes for you.

The number on the quote. Three weeks of waiting with a misfire I could feel at every stoplight. A day without the car, which for me is a shoot day, and shoot days don't reschedule — the light in October is the light in October. Two hundred miles of round trip to Asheville and back twice. And underneath all of it, the thing that actually kept me up: a job my father would have done in the driveway on a Saturday quietly becoming a job I book.

There is not one hour of that quote that is the repair. The repair is four plugs and about ten minutes of actual turning. Everything else on that invoice is somebody getting to it.

I told him I'd think about it.

I thought about it for four months.

By August I'd stopped opening the hood at all.

You know how that goes. There's a car sitting there that you're supposed to be able to fix, and you stop looking at it.

Laurie asked me once, on her way out with the dog — "You're not paying that, are you." I said no. She said "okay" and took Otis down to the trail, and she'd already worked it out. She was just waiting on me.

One evening I went out to the garage to finally do something about it and ended up doing nothing at all.

I sat down on the step. Not because I planned to. Because that's where I ended up.

My dad's twenty-five-year service medallion from the plant was on the shelf four feet from my head, still in the little velvet box. Thirty-one years he put those cars together.

And I was hiding from a spark plug.

That September I drove up to BoxerFest, at the York fairgrounds in Pennsylvania. Half swap tables, half people wrenching in the lot — the back row's called Subie Service Row and I've gone most years since it started.

Car next to me was a 2010 Outback with a wiring gremlin the owner couldn't get behind. I've chased enough of those on my own to be useful. Got him sorted. He stood up and shook my hand. Doug Mercer. Sixty-eight. Thirty-three years at the plant in Lafayette before his shoulder retired him, most of it on the fifth-generation Legacy line.

I told him my father had been there 1989 to 2020.

He knew him. Of course he knew him.

We ended up on his tailgate for the better part of an hour, and eventually I told him about the plug. The four months. The seven seventy-two. The step, eventually.

Doug chewed on that a while. Then he said, "You ever run a chain-drive bar?"

I told him I didn't know what that was.

He reached into a bag and put it in my hand.

It's a flat steel bar, about as long as your forearm. There's a square drive on each end. A socket clips onto one end and sits square on the fastener, and your hand turns the other end, six inches away, out where there's actually room to move. Inside the bar runs a steel roller chain that carries the turn from your hand around the corner to the socket. One turn in, one turn out.

I told him it looked like every offset wrench I'd ever bought and thrown in a drawer.

Doug said, "Press on the end."

I pressed. Something moved inside it. Not flex. Not wobble. A chain.

The bar doesn't turn anything. The chain does. There's no joint to fold, no coupling to deflect, nothing to walk off a plug when you load it.

I stood there working out why that mattered, and then I had it. Nothing in the path is at an angle. The socket sits flat the way a socket is supposed to sit. Every bit of damage I'd done that first evening came from something tilting, and this thing doesn't tilt. It's about six tenths of an inch thick, and that's the entire clearance it needs. Not swing room. Clearance.

Then he told me what it won't do, which is the reason I listened to the rest of it.

Fifty-three foot-pounds and the chain slips. Break a stuck fastener loose first and use this for the reach and the running out. It won't rescue a plug you've already rounded, and it won't put threads back in an aluminum head. And if your gap is tighter than six tenths, it isn't going in.

Then he said the thing I've repeated a dozen times since. "It ain't your hands, son. Everything you own wants to come straight down at that plug. That engine wants you to come in flat from the side."

I have been sold a lot of tools by men who told me they did everything. That was the first one where somebody led with the limits.

Here's what actually sold me, and it wasn't Doug.

Two rows down was a woman named Sarah Whitcomb, out of Portland, with a '16 Legacy and the same problem. Her dealer in Beaverton had quoted her eight hundred and forty dollars. She'd been driving on a misfire since spring for the same reason I had.

Doug walked over, popped the coil, worked the bar in beside the frame rail, and the socket seated flush on that back plug. No rock, no walk. Then he handed it to her.

She backed it out herself. On her own car, with her own hands, in front of me.

Six months that plug had won.

I've watched a hundred tools get demonstrated by the man selling them. That's not proof, that's a magic trick. Watching a stranger's face change on a stranger's fastener is a different thing entirely.

She said something I won't print here.

Nothing rides on the corners. The socket sits flat because nothing in the path is tilted. Load lands on the flats, where the strength is. That's the whole difference between this and a u-joint, and on a plug threaded into aluminum it isn't a nicety.

Six tenths of an inch is the requirement. If the bar lies flat between your fastener and whatever's in the way, it fits. Measure the gap at the tightest point. That's a measurement, not a promise.

It takes your own sockets. Three-eighths drive, with 3 adapters + a 1/4" hex socket in the case. Your own plug socket, your own torque wrench on the far end. Nothing proprietary, nothing to buy again.

It reaches. It's honest about the rest. A plug that's welded itself into a head at 200,000 miles cracks loose at more than this tool will ever put out — that's what soak and patience and a breaker bar are for. What it takes to run out the threads after that is a fraction of what it takes to crack it. And running them out, and running the new ones back in to torque, is exactly the part with no swing room.

Ordered one that night from the car, in the fairgrounds lot. It came the following week.

I did the plugs on a Saturday with the door rolled up and coffee on the bench.

Front two the normal way, because there's no reason not to. Then the coil off the back driver's side, the bar flat in the gap, socket square, and I felt it break. Not a slip, not a slap — a plug turning.

All four out, all four in, torqued to spec by lunch. Engine never came off its mounts. Nobody touched that car but me.

And here's the part I didn't expect, which is really why I'm writing this down.

I bought that thing for one plug. It has not been about the plug since.

The intake manifold bolts behind the throttle body. The valve cover bolts on the passenger side that the forums have a name for. A transmission cooler line under the radiator support. A starter bolt tucked behind the downpipe on my brother-in-law's '08. The belt tensioner on a neighbor's Forester that we'd both quietly agreed was a shop job.

Every one of those is the same problem wearing different clothes. A boxer lies flat, so half of what you'd ever need to reach on this car is pinned in a gap you can look straight at and can't get a tool into. Once you own the shape that fits that gap, the gap stops being the thing that decides what you're allowed to fix.

It doesn't live in the garage, either. It rides in the trunk with the camera bags, because the trouble travels with the car.

My dad's medallion is still on the shelf. The bar sits under it. Both where my hand falls, before I need either.

Built it. Drive it well.

"2018 Subaru Outback, cylinder 2 plug. Read someone else had success using BoltHero. Dealer quote came in at $850. I don't have that kinda cash."

— Carol Mcconnell, Westville, New Jersey

"Tried snubnose ratchet, long thin ratchet, no joy, dealer quoted 814.52."

— Rob Evoy, Brutus, Michigan · 2020 Crosstrek

"2019 Subaru Forester, to remove spark plugs. Dealer quoted $800 to do the job and I can't afford it."

— Thomas Kraus, Greeley, Pennsylvania

"Have a highly modified '15 Subaru STI. Took 6 hours to change the plugs once. Two hours of that were just cursing, screaming, and I'm not gonna lie, a little crying. Don't ever want to experience that little slice of hell ever again."

— Walter Riggs, Phenix City, Alabama

"I've always done my own work, and was hoping it would be as easy as it was on my 2003 Outback. Of course it's not."

— Jim Perry, Prather, California · 2016 Outback 2.5i

And one from a man who bought his before he had a job for it, for the same reason you're on this page:

"I'm going to use it on two family Subarus. That will save us $1,700."

— Kenneth Rhone, Renovo, Pennsylvania

13,000 orders shipped. 369+ reviews, 4.9 out of 5.

Do I still have to jack the engine off the mounts? No — and that's the entire reason this page exists. Loosening the mounts is what people do to buy themselves swing room for a ratchet. The bar doesn't need swing room; it needs about six tenths of an inch of flat clearance beside the plug, and it puts your hand six inches away where there already is room. That said: if you'd rather pull the mount nuts and jack it anyway, do it. Nobody gives out medals. The tool just means you don't have to.

Is this one of those Facebook things? Fair question, and you should be asking it about everything sold this way. Here's what I'd check in your position, and it works on us or anybody else. One: is the torque rating published, and is it published as a ceiling? Two: is the return window long enough to actually use the tool in? Three: who pays return shipping? Ours are 53 ft-lb, 100 days, and we do. If a seller ducks any of the three, keep your money.

Why is there a cheaper one that looks the same? Because it's nearly the same bar and several people sell it. Run the three questions above on each and buy whichever answers all three — we'd rather you bought a good one from somebody else than a bad one from us. And for what it's worth, here's a man on a tractor forum who bought a lookalike instead of ours, describing what the whole category is actually for: "I purchased an inexpensive lookalike. My anticipated use will be to remove fastener after I get it broke loose." He worked out the sequence on his own. It isn't our marketing.

I already own something like this. Then use it. The only question that decides this one is the gap at your fastener — measure it, and buy whatever fits it.

What happens past 53 ft-lb? The chain slips. That's on purpose. It's the failure mode that leaves your fastener intact instead of rounding it, and it's why the ceiling gets published instead of buried.

My plug is seized. Will this get it out? Not on its own, and be careful here — these heads are aluminum. Soak it, warm the engine, let it sit, and get it moving first. Once it's moving, this is the thing that runs it out of a hole you can't otherwise reach. If it won't start to move at all, stop and get help. A stripped plug hole is a Time-Sert and a bad week, and no tool prevents that except knowing when to quit for the night.

Will it fit my car? The bar is six tenths of an inch thick and that's all the room it needs — but it's your gap, not ours. Measure at the tightest point between the plug and the frame rail. If you've got six tenths, it goes in. If you don't, it doesn't, and no amount of wanting it to changes that.

I only have one job for it. Is it worth owning? That's the honest question and I had it too. What I'd say is what happened to me: the plugs were the reason I bought it, and they've been maybe a fifth of what it's done since. Valve cover bolts, a starter bolt behind the downpipe, a cooler line under the radiator support, the belt tensioner. On a flat engine, the plug isn't a special case. It's just the first one you meet.

Why 100 days and not 30? Because a tool like this doesn't get used the day it arrives. It goes in the case, and the case goes in the trunk, and it sits there until the job you already knew was coming finally turns up. A 30-day window on a tool that waits isn't a guarantee, it's a countdown to a refund you were never going to be able to claim. 100 days means you find your job first, use the thing on it, and then decide. No restocking fee, and you don't have to explain yourself to anybody. Two years on the chain — if it gives up, we replace it.

For what it's worth on the other side of that: under 1% of orders come back. And that's under 1% of everything we've shipped, with all of it counted — the parcels a courier damaged, the ones that turned up late or turned up wrong, every full money-back return whatever the reason the buyer gave, and the 50% partial refunds we hand anybody who tells us they aren't fully satisfied.

We could have made that number look better in four seconds by counting only the returns we'd decided were our own fault. That's how most numbers like this get built, and it's why most of them are worth nothing. Under 1%, everything in.

If your plug is seized into the head and won't start to move, this isn't your afternoon. Soak it, warm it, come back to it, and don't let anybody sell you a shortcut around that.

But if your problem is the one I had — you can see the thing, you can put a finger on the thing, and there is nowhere to put a wrench on it straight — then what you've got is a room problem. And room problems have a tool.

I paid four months and a step in the garage to learn it.

30% off right now. Free tracked shipping, 6–12 days · 100 days to send it back, no restocking fee · 2-year warranty on the chain

You don't have to unbolt the engine to change a spark plug. You just have to come at it from the side.

The owner quotes in "Other people who stopped paying for access" are from the BoltHero owner survey, published with the names and vehicles as given. Where a respondent wrote a dollar figure, it is theirs, unrounded. Carol Mcconnell's and Rob Evoy's cylinder numbers are quoted as they wrote them.

The forum quotes in "The one on the driver's side, in the back" are from public threads on the Subaru Outback and Subaru Forester owner forums, including the thread titled "Really?? Engine removal for spark plugs?" The instruction to remove the motor mount nuts and jack the engine also appears in published DIY guides for the FB25.

Cylinder numbering on the 2.5 boxer, per the factory service manual: #1 front right, #3 rear right, #2 front left, #4 rear left. Firing order 1-3-2-4. The plug described in this report is the rear left — driver's side, in the back, on a US-market car.

The lookalike quote in the FAQ is from a public thread on Yesterday's Tractors, from a poster who states he bought a competing tool, not ours.

53 ft-lb / 72 Nm is the rated ceiling. Beyond it the chain slips rather than transferring more torque to the fastener.

The tool is 15.4 in long, 0.62 in thick, 730 g, A3 carbon steel, 3/8" drive with 3 adapters + a 1/4" hex socket and a case. Founded and designed in the US. Shipping is free and tracked, 6–12 days in the US.

The returns figure — under 1% of orders — is our own order data across 13,000 orders shipped, and it counts shipping damage, late and incorrect deliveries, full money-back returns and the 50% partial refunds given to any buyer who says they aren't fully satisfied. Reviews are the store's own: 369+ at 4.9 out of 5.

Not affiliated with Subaru Corporation or with Subaru of Indiana Automotive.