- +Unusually complete spec disclosure: CFM, max amperage, duty cycle and fill rates at a stated 13.8 V supply
- +HornBlasters publishes its 3 ft and 100 ft test distances and argues publicly against inflated dB claims
- +Lifetime manufacturer's-defect warranty on the horns, 2 years on every other component
- +Everything is in the box down to D.O.T. air line, a fused wiring loom, blow-off valve, air line cutter and earplugs
- +One-bracket design cuts HornBlasters' own install estimate from 6-8 hours to roughly 3-5 hours
- +Serviceable long-term — individual bells, S4 diaphragm kits, bracket feet and both compressors sold separately
- −No decibel figure published on the kit page at all; the 147.7 dB rating belongs to the standalone horn listing
- −You lose the spare tire and HornBlasters offers no alternative carrier
- −Hangs below the frame — the brand's own Stealth kit is sold on giving five inches more ground clearance
- −$999.99 is top-of-market for a 2-gallon build whose 3Q compressor needs nearly four minutes to fill a dry tank
- −Marketed as ready-to-install, but the page confirms it ships as loose components and requires assembly
- −2020-2021 Chevy and GMC 1500 and 3500 need the mounting point modified; mid-size trucks sit low
Methodology
This review aggregates publicly available information from manufacturer specifications, retailer listings, and verified user reviews. We do not perform hands-on testing. Last reviewed September 20, 2026. Every figure below comes from HornBlasters’ own Spare Tire Delete Kit listing, its standalone Shocker XL horn page, its published decibel-testing policy, or the owner install threads and video demos listed in the Sources section at the end. Where HornBlasters publishes no number, we say so rather than filling the gap with an estimate.
Quick verdict
We rate the HornBlasters Spare Tire Delete Kit 4.3/5. It is one of the most completely documented train horn kits sold in the US: HornBlasters publishes trumpet lengths, tank dimensions, compressor CFM, maximum amperage, duty cycle and stopwatch fill rates measured at a stated 13.8-volt supply, which is more than most competitors disclose for any product at any price. The catch is the total ask — $999.99 or $1,299.99 depending on which compressor you pick, plus the permanent loss of your spare tire. Our editorial opinion: buy this kit for the documentation, the lifetime horn warranty and the single-bracket install, not because the marketing copy calls it “ready-to-install.”
What it is
The Spare Tire Delete Kit — HornBlasters trademarks the name as Spare Tire Delete® — is a complete four-trumpet train horn and onboard air system pre-engineered to occupy the space under a pickup bed where the spare tire normally hangs. Rather than finding three separate homes for a horn, a tank and a compressor, you bolt all of it to one 14-gauge powdercoated steel bracket and crank the finished assembly into position with the factory spare tire winch, exactly the way the tire went up.
The horn is the Shocker XL (part number AH-S4), a four-bell design made in the US from fiberglass-reinforced ABS with stainless steel internals and brass fittings. Air comes from a HornAir 2-gallon, six-port tank. The kit ships in two configurations that differ only in the compressor: the Medium-Duty version pairs the tank with HornBlasters’ 3Q compressor at $999.99, and the Heavy-Duty version uses the 1NM Stealth Black compressor at $1,299.99. Both are offered with a black or a white horn finish.
The target buyer is narrow and obvious — a full-size pickup owner who has already fitted oversize tires, which makes the factory spare useless anyway.
Specifications
| Spec | Value |
|---|---|
| Part numbers | HK-S4-232-STDK (Medium-Duty) / HK-S4-244K-STDK (Heavy-Duty) |
| Horn | Shocker XL (Shocker S4), four trumpets |
| Trumpet lengths | 19.50 in / 16.25 in / 14.75 in / 12.75 in (495.30 / 412.75 / 374.65 / 323.85 mm) |
| Bell flare | 5 in (127 mm) |
| Horn material | Fiberglass-reinforced high-impact ABS, stainless steel internals, brass fittings |
| Horn weight | 4.5 lb (2.04 kg) |
| Sound output | Not published on the kit page; HornBlasters rates the standalone Shocker XL horn at 147.7 dB “Actual dB” |
| Operating pressure | 150 PSI cut-out / 110 PSI cut-in |
| Honk time | 3-5 seconds from a full 2-gallon tank |
| Voltage | 12-volt DC |
| Air tank | HornAir 2-gallon six-port — 17 in long, 6 in diameter, 7 in tall with legs, 10 lb |
| Compressor (Medium-Duty) | HornBlasters 3Q — 1.41 CFM at 0 PSI, 20 A max, 100% duty cycle at 100 PSI, 10.1 x 4.5 x 7 in |
| Compressor (Heavy-Duty) | HornBlasters 1NM Stealth Black — 1.75 CFM at 0 PSI, 25 A max, 100% duty at 100 PSI / 50% at 200 PSI |
| Fill rate (Medium-Duty) | 0-150 PSI in 3 min 59 sec (±10 sec); 110-150 PSI in 1 min 33 sec (±5 sec) |
| Fill rate (Heavy-Duty) | 0-150 PSI in 2 min (±10 sec); 110-150 PSI in 35 sec (±5 sec) |
| Bracket | 14-gauge steel, two-stage powdercoat — 19 x 19 x 7.5 in, 6 lb |
| Assembled dimensions | 21 in L x 23 in W x 13 in H |
| Assembled weight | 40 lb |
| Air valve | Black Widow 1/2 in NPT stainless steel electric air valve |
| Power source | Air tank with 12-volt onboard compressor |
| Price | $999.99 Medium-Duty / $1,299.99 Heavy-Duty (list prices $1,199.99-$1,353.98) |
| Warranty | Lifetime manufacturer’s-defect on the horns; 2 years on all other components |
Both fill-rate figures are published against a 13.8-volt supply, which is the detail that makes them comparable rather than decorative — a compressor tested at a lower resting battery voltage will always look slower. For context on why that matters, see our guide to compressor duty cycle.
What’s in the box
- Shocker XL four-trumpet train horn (black or white)
- Spare Tire Delete steel bracket with mounting hardware
- HornAir 2-gallon six-port air tank
- HornBlasters 3Q compressor (Medium-Duty) or 1NM Stealth Black compressor (Heavy-Duty)
- 110/150 PSI pressure switch with 40 A relay
- Remote-mountable intake filter assembly plus spare filter elements
- 10 ft of 5/16 in and 17 ft of 1/2 in D.O.T.-approved air line, plus 6 ft of 3/8 in line for the compressor intake
- Black Widow 1/2 in NPT stainless steel electric air valve
- HornBlasters 200 PSI stainless steel liquid-filled air gauge
- Brass NPT fittings kit including a safety blow-off and drain cock
- 22 ft of power wire (10-gauge on the Medium-Duty, 8-gauge on the Heavy-Duty) plus 22 ft each of 18-gauge blue and grey
- Complete wiring kit with fuse holder and fuses
- Air line cutter, earplugs and printed instructions
The earplugs are not a gag. At the output this horn is claimed to produce, standing beside it while someone tests the button is a genuine hearing risk — our guide on whether a train horn can damage hearing covers the exposure math.
Pros
- Spec disclosure is unusually complete — CFM, maximum amperage, duty cycle, stopwatch fill rates at a stated supply voltage, and bracket, tank and assembled dimensions are all published
- HornBlasters states its decibel test distances (3 ft and 100 ft) and publicly argues against inflated ratings, which is rare in a category built on 150 dB claims
- Lifetime manufacturer’s-defect warranty on the horns and two years on every other component, plus a 30-day satisfaction replacement or refund guarantee
- Genuinely complete: three sizes of D.O.T.-spec air line, a fused wiring loom with a 40 A relay, brass fittings, blow-off valve, drain cock, an air line cutter and earplugs are all in the box
- Consolidating horn, tank and compressor onto one bracket cuts HornBlasters’ own install estimate from 6-8 hours to roughly 3-5 hours
- Serviceable long-term — individual Shocker XL bells, S4 diaphragm kits, replacement bracket feet and both compressors are sold separately by the brand
Cons
- The kit page publishes no decibel figure at all; the 147.7 dB “Actual dB” number belongs to the standalone Shocker XL horn listing, and HornBlasters never states which of its two test distances produced it
- You give up the spare tire and HornBlasters offers no alternative carrier — a real liability on a truck driven far from a tire shop
- The assembly hangs below the frame rails, and HornBlasters’ own Stealth kit is marketed on delivering five inches more ground clearance, which reads as an admission about this bracket
- At $999.99 for a Medium-Duty build whose 3Q compressor needs nearly four minutes to fill a dry tank, the price is top-of-market for a 2-gallon four-trumpet setup
- ”Complete & ready-to-install” oversells it — the product page confirms the kit arrives as individual components and assembly is required
- Fitment is not universal: 2020-2021 Chevy and GMC 1500 and 3500 trucks need the mounting point modified, and HornBlasters warns the bracket “may sit lower than you’d like” on mid-size trucks
Alternatives
- HornBlasters Shocker XL horn on its own — the same four trumpets without the bracket, tank or compressor. The right call if you already run onboard air or air suspension and only need the noise.
- HornBlasters Conductor’s Special 232 — effectively the same Shocker XL plus 2-gallon plus 3Q package sold without the spare tire bracket, so you choose your own mounting locations and keep the spare.
- Kleinn USTL-230 — the closest direct competitor in the spare-tire-location format, with a three-trumpet horn and a larger 3-gallon tank, but a shorter component warranty.
- HornBlasters Stealth Spare Tire Delete Kit — the brand’s own successor at $1,279.99 to $1,539.99, which tucks the bells up into the spare tire well for more clearance and is the version that supports a 5-gallon tank. Worth pricing out before you commit to this one.
More of the brand’s lineup is indexed on our HornBlasters reviews hub.
Install / compatibility notes
HornBlasters estimates 3-5 hours with basic hand tools and general 12-volt knowledge, versus the 6-8 hours a conventional scattered install takes. That estimate assumes you assemble the bracket first — the kit ships flat-packed — and then use the spare tire winch to lift roughly 40 pounds of finished assembly into the tire well.
- Electrical
- 12 V DC; 20 A max draw (3Q) or 25 A max (1NM), fed by the supplied 10-gauge or 8-gauge power wire and 40 A relay
- Clearance needed
- 21 x 23 x 13 in assembled; adding the optional Shocker S6 extensions widens it from 20 in to 29 in
- Known fitment exceptions
- 2020-2021 Chevy and GMC 1500 and 3500 require modification at the mounting point
- Pressure control
- Pre-set 110/150 PSI switch; safety blow-off and drain cock included
HornBlasters describes the bracket as fitting most full-size pickups, and its selection page broadens that to full-size and mid-size pickups plus SUVs while cautioning that on mid-size trucks it “may sit lower than you’d like.” The company states plainly that the bracket is not 100% plug-and-play with every vehicle and asks unsure buyers to call before ordering — advice worth taking, because a bracket that fouls a hitch receiver or an exhaust hanger is not a return you want to ship back.
Two practical notes from the documentation. First, mount the remote intake filter somewhere dry and high; the compressor pulls its air through 6 ft of 3/8 in line precisely so the filter does not have to live in the spray zone under the bed. Second, drain the tank on a schedule — the drain cock is included for a reason, and underbody tanks in salted states collect condensation fast. Our walkthrough on draining a train horn tank covers the interval.
On loudness, be clear-eyed about what is and is not documented. HornBlasters publishes a 147.7 dB “Actual dB” rating for the Shocker XL horn and separately states that it measures at 3 ft and 100 ft with calibrated meters, that a Nathan AirChime K5 registered 149.4 dB at 3 ft as the loudest horn it has tested, and that every non-electric horn it sells measures above 130 dB. The kit page itself carries no number. Treat 147.7 dB as a manufacturer figure for the horn rather than a certified rating for this kit, and check your state rules on our legality pages before wiring the button — see also our explainer on what 150 dB actually means.
Owner install posts on Train Horn Forums for 2026-model Tundra and Silverado 2500 HD builds show the format working cleanly on late-model full-size trucks, though those write-ups are promotional in tone and report no install times or problems, so we treat them as evidence the fitment exists rather than as independent reliability data.
Sources
- HornBlasters — Spare Tire Delete® Kit product page — part numbers, both prices, full spec tables for both compressor configurations, fill rates, honk time, tank and bracket dimensions, assembled weight, included items, warranty terms, fitment warnings and the S6 extension width note
- HornBlasters — Shocker XL Train Horn product page — trumpet lengths, 5 in flare, 4.5 lb horn weight, 150 PSI max working pressure, US manufacture, fiberglass-reinforced ABS and stainless construction, lifetime warranty, and the “1.7 dB difference” claim
- HornBlasters — Train Horn Decibels Explained: Why Fake Ratings Mislead Buyers — the brand’s 3 ft and 100 ft test methodology, the 149.4 dB Nathan AirChime K5 figure, and the “130+ dB” claim for its non-electric horns
- Amazon — HornBlasters Shocker XL Train Horns Only, US Made Horns, 147.7 Actual dB — the 147.7 dB “Actual dB” rating quoted for the Shocker XL horn
- HornBlasters — Spare Tire Delete® Train Horn Kit Selection — the 3-5 hour install estimate, full-size/mid-size/SUV fitment guidance, and the “may sit lower than you’d like” caution
- HornBlasters — Spare Tire Delete Functionality & Capabilities — winch-crank operation, tools required, and the redesigned bracket that supports a 5-gallon tank
- HornBlasters — Stealth Spare Tire Delete® Kit — $1,279.99-$1,539.99 pricing and the 2- and 5-gallon options cited in Alternatives
- HornBlasters — Stealth Spare Tire Delete® Bracket — bracket-only pricing used to judge kit value
- HornBlasters — Shocker S6 Upgrade Extensions for Spare Tire Delete Brackets — the optional extension referenced in the clearance notes
- HornBlasters — Spare Tire Delete Replacement Foot — evidence that bracket hardware is sold as a serviceable spare part
- HornBlasters — Shocker XL S4 Diaphragm Kit — replacement diaphragms backing the long-term serviceability point
- YouTube — HornBlasters Spare Tire Delete Kit Install — the manufacturer’s install walkthrough linked from the product page
- YouTube — HornBlasters Review from DJD Labs — the third-party side-by-side loudness demo HornBlasters links as a customer video review
- Train Horn Forums — 2026 Chevrolet Silverado 2500 HD Z71 Spare Tire Delete install — owner install post cited as a user report on late-model full-size fitment
- Train Horn Forums — 2026 Toyota Tundra Spare Tire Delete install — second owner install post cited as a user report
Train Horn Hub aggregates publicly available data. We do not test products in-house. All trademarks belong to their respective owners.
The Spare Tire Delete Kit is the right buy for a full-size pickup owner who has already written off the factory spare and wants a four-trumpet train horn, tank and compressor installed in one afternoon on one bracket. Price out the brand's own Stealth version first if ground clearance or keeping the spare hanger matters to you.
Frequently asked questions
Quick answers to the questions people ask most about this topic.
- How loud is the HornBlasters Spare Tire Delete Kit?
- HornBlasters publishes no decibel figure on the kit page itself. Its standalone Shocker XL horn listing carries a 147.7 dB 'Actual dB' rating, and the brand states it measures horns at 3 ft and 100 ft with calibrated meters without tying either distance to that number. Treat 147.7 dB as a manufacturer claim for the horn rather than a certified rating for the complete kit.
- Do I lose my spare tire with this kit?
- Yes. The bracket replaces the spare tire entirely in the under-bed tire well and winches up on the factory hoist in its place. HornBlasters does not supply an alternative spare carrier, so plan for a repair kit, a portable inflator or a bed-mounted spare before you commit.
- What is the difference between the Medium-Duty and Heavy-Duty versions?
- Only the compressor. The $999.99 Medium-Duty kit uses HornBlasters' 3Q compressor rated 1.41 CFM at 0 PSI and 20 A max, refilling 110-150 PSI in 1 minute 33 seconds. The $1,299.99 Heavy-Duty kit uses the 1NM Stealth Black rated 1.75 CFM and 25 A max, covering the same 110-150 PSI range in 35 seconds. Horn, 2-gallon tank, bracket and hardware are identical.
- How long does the Spare Tire Delete Kit take to install?
- HornBlasters estimates 3-5 hours with basic hand tools and general 12-volt knowledge, compared with the 6-8 hours it quotes for a conventional install with separately mounted components. Budget extra time up front because the kit arrives as individual parts and the bracket has to be assembled before it goes under the truck.
- Will it fit my truck?
- HornBlasters says it fits most full-size pickups and extends that to mid-size pickups and SUVs with the caveat that on mid-size trucks the bracket 'may sit lower than you'd like.' It specifically flags that 2020-2021 Chevy and GMC 1500 and 3500 trucks require modification at the mounting point, and states the bracket is not 100% plug-and-play with every vehicle.
