Snow Blower Shear Pins

Why a part is designed to break

A two-stage snow blower's auger is driven through a gearbox that costs a significant fraction of the machine. The auger is also the part that meets whatever the snow was hiding: a frozen newspaper, a chunk of plow ice, a rock at the edge of a gravel drive.

When it meets one of those and stops dead, something has to give. The shear pin is a deliberately weak fastener chosen to be that something — it snaps, the auger free-wheels on its shaft, and the drivetrain behind it survives. Husqvarna says it plainly in its own listing: the objective is for the shear bolt to break.

That design intent is the whole reason this page exists, because it inverts normal buying instinct. In every other part of your machine, stronger is better. Here, stronger is a defect.

The mistake that costs a gearbox

The failure pattern is depressingly common. A pin breaks on a Sunday, the hardware store is open and the dealer is not, and a grade 5 bolt of the right diameter goes in "just for now".

That bolt is several times stronger than the pin it replaced. The next time the auger hits something, the bolt does not break — so the energy travels into the auger shaft, the bearings and the gearcase, and what would have been a two-dollar part becomes a repair worth hundreds.

The same logic is why we are cautious about aftermarket pin kits that advertise "high-quality" and "sturdy" metal without stating a grade. Hardness is not a selling point on this part; specification is.

Identifying the pin your machine takes

1. 01Look for the part number in the manual first. Snow blower manuals list the shear pin number in the maintenance section, and it is the only fully reliable answer.
2. 02Otherwise, measure the broken pin: diameter and length. The two common patterns are quarter-inch by about 1.65 inches (MTD family) and quarter-inch by 1 9/16 inches (Husqvarna family).
3. 03Note the retaining method. Most use a cotter pin through the end; some use a nut. Buy the kit that includes the right retainer, because the cotter is the part that disappears into the snow during the repair.
4. 04Check how many your machine uses. Two-stage machines commonly run two or four, and the auger may use a different pin from the impeller.
5. 05Match the family, not the brand on the hood. MTD builds Cub Cadet, Troy-Bilt, Craftsman, Yard Machines, Huskee and Bolens machines that share the same pin.

Quick picks

Ranked against the criteria below. Tap a row to jump to the full write-up; the price button goes straight to Amazon.

#	Product	Best for	Score	Price
1	Husqvarna Shear Bolts and Nuts Kit, 6-Pack The OEM kit, with the part numbers it replaces printed on the listing and the bolt dimensions published — which is exactly what you want from a part designed to break.	Husqvarna and Poulan two-stage machines	8.4/10★★★★★	$9.49 - View on Amazon #ad affiliate link · Price as of September 21, 2026
2	Bayocean Shear Pin and Cotter Pin Kit, 738-04124A The common MTD-pattern pin, 1/4 inch by 1.65 inches, with the matching cotter pins and the part numbers stated plainly. Our skip-this pick	MTD-family machines — Cub Cadet, Troy-Bilt, Craftsman, Yard Machines	7.2/10★★★★★	$5.99 - View on Amazon #ad affiliate link · Price as of September 21, 2026
3	Potiarey Shear Pin and Cotter Pin Set, 30 Sets, MTD Pattern Thirty sets of the MTD-pattern pin and cotter — the bulk option, which is either exactly what a gravel driveway needs or twenty-eight more than you will ever use.	A gravel drive that eats pins, or several machines	7.1/10★★★★★	$16.99 - View on Amazon #ad affiliate link · Price as of September 21, 2026

01

Husqvarna and Poulan two-stage machines

Husqvarna Shear Bolts and Nuts Kit, 6-Pack

The OEM kit, with the part numbers it replaces printed on the listing and the bolt dimensions published — which is exactly what you want from a part designed to break.

A shear pin is a fastener engineered to fail. It holds the auger to its shaft, and when the auger hits something it cannot pass — a newspaper, a chunk of ice, a rock — the pin snaps so the auger stops instead of the gearbox tearing itself apart. Replacing it is a five-minute job; replacing a gearbox is not.

That design intent is why the grade of the bolt matters more than its dimensions. A pin that is stronger than specified does not protect your machine better; it protects it less, because the force that should have snapped a cheap bolt instead goes into the auger shaft, the bearings and the gearcase.

Husqvarna's kit is the straightforward answer for its own machines and Poulan's. It publishes the bolt dimensions, lists every superseded part number so you can confirm fitment on a ten-year-old blower, and — being OEM — is the grade the engineers chose.

Keep the spares somewhere you can reach in the dark with cold hands, because a pin never breaks in the garage. Tape a couple inside the chute cover or the fuel-cap area of the machine itself.

If you are breaking pins often, the pin is not the problem. Either the surface is feeding stone into the auger — see using a snow blower on gravel — or the skid shoes are set too low.

What works

• +OEM, so the bolt is the grade the machine was designed to break — the whole point of the part
• +Publishes actual bolt dimensions rather than just a part number
• +Lists the superseded numbers, which is how you confirm fitment on an older machine
• +Six is the right number: enough for several jams, not a lifetime of clutter

What does not

• −Husqvarna and Poulan only — the wrong kit for an MTD-family machine
• −Costs more per pin than the generic multipacks
• −Six bolts will not last a season on a gravel drive that jams the auger regularly
• −Nothing here helps if the real problem is that you are feeding the machine stone

02

MTD-family machines — Cub Cadet, Troy-Bilt, Craftsman, Yard Machines

Bayocean Shear Pin and Cotter Pin Kit, 738-04124A

The common MTD-pattern pin, 1/4 inch by 1.65 inches, with the matching cotter pins and the part numbers stated plainly.

Skip this one

If your machine is under warranty, or it is a big two-stage you rely on, buy the manufacturer's own pins. Aftermarket kits like this one publish dimensions but not the shear grade, and a pin that is too hard transfers an impact that should have broken a bolt into the auger shaft and gearcase instead. This is the right buy for an older, out-of-warranty machine you maintain yourself.

The 738-04124 pattern is the pin the MTD group uses across an enormous number of machines sold as Cub Cadet, Troy-Bilt, Craftsman, Yard Machines, Huskee and Bolens. If your blower came from that family, this is almost certainly the pin in your auger.

What this kit gets right is the boring, useful part: it states the pin dimensions — quarter inch by 1.65 inches — and it includes the cotter pins. Cotters are the parts that vanish into the snow during the repair and are never in the drawer when you need one.

What it does not state is the shear grade, and that is the specification that matters. Every one of these aftermarket listings says "high-quality metal" and none says what load the pin is designed to fail at. Made too hard, it stops being a fuse.

So the honest position: for an out-of-warranty machine you look after yourself, this is a sensible, cheap way to keep spares in the garage. For a machine still under warranty, or a large two-stage you cannot afford to lose mid-winter, pay the difference for the maker's own pins.

Either way, replace with the machine off and the plug pulled, and clear the jam with a tool rather than a hand — see how to use a snow blower on gravel for the habits that cause fewer jams in the first place.

What works

• +Covers the single most common pin pattern on the market, across four big brand families
• +Cotter pins included — the part everyone loses and nobody stocks
• +States the pin dimensions, so you can measure your broken one against it before ordering
• +Cheapest way here to get back running

What does not

• −Aftermarket: the listing says sturdy metal but never states the shear grade, and grade is the entire specification
• −"Compatible with" lists are not the same as an OEM fitment guarantee
• −A pin that does not shear when it should can cost you a gearbox — the saving is small against that risk
• −No mounting hardware beyond the pins themselves

03

A gravel drive that eats pins, or several machines

Potiarey Shear Pin and Cotter Pin Set, 30 Sets, MTD Pattern

Thirty sets of the MTD-pattern pin and cotter — the bulk option, which is either exactly what a gravel driveway needs or twenty-eight more than you will ever use.

There is exactly one good reason to own thirty shear pins, and it is a gravel driveway. A two-stage machine working over stone will find something to swallow several times a winter, and each time the pin does its job you need another one.

For that household this pack is the right answer: pins and cotters matched, broad MTD-family fitment, and cheap enough that keeping a handful taped to the machine and the rest in the garage costs nothing.

For everyone else it is thirty pins in a drawer. A paved drive that is cleared after the snow stops rather than during it might break one pin in three seasons.

The caveat is the one that applies to all aftermarket pins: the shear grade is not published. If the machine matters to you, keep a few OEM pins for the real repairs and use these when you are clearing an unfamiliar surface and expect to break something.

And take the hint the pins are giving you. Breaking them repeatedly means the auger is reaching the stone, which is a skid-shoe height problem before it is a pin problem — snow blower skid shoes covers setting that.

What works

• +Thirty sets means you never postpone a repair because you are out of pins
• +Broadest stated fitment list of the aftermarket kits here
• +Cotter pins matched one-for-one with the shear pins
• +Cheap per pin by a wide margin

What does not

• −Same unstated shear grade as every aftermarket kit — quantity does not fix that
• −Thirty sets is a decade of pins for a paved driveway
• −The listing names series numbers but no bolt dimensions, so measure before you buy
• −Loose pins in a bag turn into loose pins in a drawer

Replacing one, step by step

1. 01Shut it down properly. Engine off, key out, plug lead off.
2. 02Clear the jam first with a clearing tool or a piece of wood — not with a hand, and not with the machine running.
3. 03Rotate the auger until the hole in the auger lines up with the hole in the shaft.
4. 04Push the broken halves out. A punch and a light tap usually does it; penetrating oil helps on a machine that has been salted for years.
5. 05Fit the new pin and its cotter, and spread the cotter legs so it cannot walk out.
6. 06Grease the auger shaft zerks if your machine has them, since a seized auger on its shaft is a common reason pins keep breaking.

If you are breaking pins often, the pin is not the problem

One or two a season on a gravel drive is normal. Several in a storm is the machine telling you something.

• Skid shoes set too low — the auger is reaching stone it should be riding over. That is the first thing to check, and snow blower skid shoes covers the setting.
• Clearing too fast in deep or wet snow, so the auger takes bites it cannot swallow.
• A seized auger bushing, which stops the auger rotating freely on the shaft and puts the whole load on the pin.
• Debris hidden under fresh snow — a length of hose, a dog toy, a chunk of plow ice at the apron. Walk the drive before the first snow and again after a thaw.

And if your driveway is gravel, the broader setup matters more than the pins: using a snow blower on gravel and gravel driveways both go through it.