- +True vehicle-specific bolt-on brackets for 2014-2026 RAM HD — no drilling, cutting, or welding per Kleinn
- +Flagship Demon 730 stainless triple horns rated 157.8 dB at 150 PSI
- +Fully submersible, waterproof 6450RC compressor with 100% duty cycle at 100 PSI
- +Doubles as a real onboard air system — 24-ft hose, tire inflator gauge, rated for tires up to 39 inches
- +Extended 2-year warranty on both compressor and horn assembly
- −At $1,599.95 it is one of the most expensive bolt-on train horn kits sold
- −No test distance published for the 157.8 dB rating
- −The kit page itself doesn't state a dB number — you have to cross-reference the Demon 730 horn page
- −3-gallon tank is the practical minimum for horns this air-hungry, so long blasts drain it quickly
- −Full onboard-air plumbing — bolt-on brackets don't make the wiring and airline work trivial
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: August 25, 2026. Primary sources for this article are Kleinn’s official product pages for the RAMHD-734 kit, the Demon Model 730 horns, and the 6450RC compressor, cross-checked against RealTruck’s retail listing. Every external URL we relied on is listed in the Sources section at the end.
Quick verdict
The Kleinn RAMHD-734 is the RAM HD version of Kleinn’s direct-fit flagship formula: take the loudest horn in the catalog, pair it with the toughest compressor in the catalog, and hang everything on brackets engineered for one specific truck so nothing needs to be drilled, cut, or welded. At $1,599.95 it costs as much as some complete lift kits, but you’re getting the 157.8 dB Demon 730 stainless horns, a waterproof 200 PSI compressor with a 100% duty cycle at 100 PSI, and a legitimate onboard air system that airs up to 39-inch tires. We rate it 4.4/5 — the main deductions are the price and Kleinn’s habit of publishing dB figures without a test distance. For a 2014-2026 RAM 2500/3500 owner who wants maximum output with a factory-clean install, this is the strongest single-box answer on the market.
What it is
The RAMHD-734 (P/N KL RAMHD-734) is a vehicle-specific train horn and onboard air package for 2014-2026 RAM HD 2500 and 3500 trucks. Kleinn sells it on one product page with three kit-type options: the Model 730 system reviewed here at $1,599.95, a cheaper Model 230 system that swaps in Beast ABS horns and the 150 PSI 6350RC compressor with 1/4-inch airline, and an onboard-air-only system without horns. This review pins the flagship 730 variant.
The headline claim is the install: Kleinn calls it a “100% bolt-on design — no drilling, no cutting, no welding.” Custom brackets locate the Demon 730 horn rack and the air system in factory positions on the RAM HD chassis, which is the core difference between this kit and a universal system like the ones covered in our Kleinn reviews hub.
Who it’s for: RAM HD owners who want the loudest street-legal-where-permitted hardware Kleinn makes, plus working onboard air for tires, tools, and trailers, and who would rather pay for engineered brackets than spend a weekend fabricating. If you drive a Ford Super Duty or GM HD instead, Kleinn builds the same concept as the SDKIT17-734 and GMHD-734.
Specifications
| Spec | Value |
|---|---|
| Part number | KL RAMHD-734 |
| Fitment | 2014-2026 RAM HD 2500/3500 |
| Horns | Demon Model 730 stainless steel triple train horns |
| Sound output | 157.8 dB at 150 PSI (test distance not disclosed) |
| Horn material | Stainless steel and zinc alloy, XCR 2.0 black coating |
| Horn rack dimensions | 22.5” L × 18.5” W × 7.25” H |
| Solenoid | VX6003 heavy-duty brass, pre-fitted |
| Compressor | Kleinn 6450RC, 200 PSI max, waterproof/fully submersible |
| Duty cycle | 100% at 100 PSI |
| Compressor flow / draw | 2.1 CFM at 0 PSI; 23 A max |
| Air tank | 3.0-gallon steel, Cortec internally coated (per retailer listing) |
| Airline | 1/2” Max-Flow delivery to horns |
| Tire inflation | Up to 39” tires; 24-ft hose with quick-connect couplers |
| Install | 100% bolt-on; no drilling, cutting, or welding |
| Warranty | Extended 2-year on compressor and horn assembly |
| Price | $1,599.95 (in stock at publication) |
Two numbers deserve context. First, the 157.8 dB figure comes from Kleinn’s Demon 730 horn page, measured at 150 PSI — the kit page itself doesn’t print a dB rating, and no test distance is disclosed anywhere, which matters because distance changes dB readings enormously (see our guide to advertised vs real-world decibels). Second, the 6450RC is rated for tanks up to 7 gallons, so the included 3-gallon tank leaves headroom if you later add a second tank.
What’s in the box
- Demon Model 730 stainless triple train horns with pre-fitted VX6003 brass solenoid
- 6450RC waterproof 200 PSI compressor with snorkel-style remote intake
- 3-gallon steel air tank (per retailer listing) with automated pressure switch
- Vehicle-specific mounting brackets for horns and air system
- Heavy-duty 24-ft coiled air hose with quick-connect couplers
- Luminescent tire inflator gauge with glow-in-the-dark face
- Coupler relocation kit with 12 ft of airline
- Complete wiring — relay, wire, loom — plus horn button, fittings, airline, and mounting hardware
- Custom canvas storage bag for the inflation kit
Pros
- Vehicle-specific bolt-on brackets for 2014-2026 RAM HD — Kleinn claims no drilling, cutting, or welding anywhere in the install
- Demon 730 horns are Kleinn’s flagship: stainless construction and a 157.8 dB rating at 150 PSI
- The 6450RC is genuinely overbuilt — fully submersible, waterproof, and rated for 100% duty cycle at 100 PSI
- Real onboard air utility: 24-ft hose, inflator gauge, and enough capacity for tires up to 39 inches
- Extended 2-year warranty covers both the compressor and the horn assembly
- 1/2-inch Max-Flow airline feeds the horns properly instead of choking them with narrow tubing
Cons
- $1,599.95 puts it near the top of the entire bolt-on train horn market
- No test distance is published for the 157.8 dB rating, so it can’t be compared apples-to-apples against brands that measure at a stated distance
- The kit page omits the dB number entirely — buyers have to dig it out of the separate Demon 730 listing
- A 3-gallon tank meets the 730’s 2.5-gallon minimum but empties fast with repeated long blasts
- Full onboard-air plumbing means this is still a multi-hour weekend install despite the bolt-on brackets
Alternatives
- Kleinn Demon 730 standalone — the same horns without brackets or air system, for builders assembling a custom setup around their own compressor and tank. See our Kleinn Demon 730 review.
- Kleinn SDKIT17-734 — the identical 730-plus-onboard-air formula in a bolt-on package for 2017+ Ford Super Duty trucks. See our SDKIT17-734 review.
- Kleinn GMHD-734 — the GM HD 2500/3500 version of the same direct-fit system, reviewed in our GMHD-734 review.
If $1,600 is out of reach, the Model 230 variant on the same Kleinn page keeps the bolt-on brackets and onboard air but drops to ABS Beast horns and the 150 PSI 6350RC compressor.
Install / compatibility notes
The kit fits 2014-2026 RAM HD 2500 and 3500 trucks; it is not listed for RAM 1500s, which use different frames (our RAM train horn guide covers those options). Everything mounts to existing chassis points with the supplied brackets. Plan for these realities:
- Electrical: the 6450RC draws up to 23 A, so the supplied relay and wiring must go straight to the battery with the included loom — see our guide to amp draw, fuses, and wire gauge.
- The automated pressure switch manages tank fill; at 200 PSI system pressure, leak-checking every fitting on first fill is essential (bench-test guide).
- The horn button wires independently of the factory horn circuit, which sidesteps the CAN bus complications covered in our BCM horn circuit guide.
- The coupler relocation kit lets you put the quick-connect air fitting somewhere reachable — worth doing during the initial install rather than after.
Editorially, we’d budget a full day for a careful first-time install even with no drilling involved: the tank, compressor, horn rack, wiring, and airline runs are each simple, but there are a lot of them.
Sources
- Kleinn — Bolt-on Train Horns & Onboard Air Kit for 2014-2026 RAM 2500/3500 — kit price ($1,599.95), part number, in-stock status, variant options, included items, no-drill install claim, 39” tire rating, 24-ft hose, extended 2-year warranty, 1/2” Max-Flow airline
- Kleinn — Model 730 “Demon” Stainless Steel Triple Train Horns — 157.8 dB at 150 PSI rating, stainless/zinc-alloy construction, 22.5” × 18.5” × 7.25” rack dimensions, VX6003 solenoid, 200 PSI max, 2.5-gallon minimum tank, $599.95 standalone price
- Kleinn — Model 6450RC Waterproof 200 PSI Compressor — 200 PSI max, 100% duty cycle at 100 PSI, 2.1 CFM at 0 PSI, 23 A draw, fully submersible waterproof design, 7-gallon max tank, $299.95 standalone price
- RealTruck — Kleinn Bolt-On Train Horn Kit RAMHD-734 — $1,599.95 price cross-check, 3.0-gallon US-made Cortec-coated steel tank, SAE J10 and FMVSS 121 manufacturing standards
Train Horn Hub aggregates publicly available data. We do not test products in-house. All trademarks belong to their respective owners.
The RAMHD-734 is the no-compromise pick for 2014-2026 RAM 2500/3500 owners who want Kleinn's loudest stainless horns plus genuine onboard air in one bolt-on, warranty-backed package — if the $1,600 price fits the budget.
Frequently asked questions
Quick answers to the questions people ask most about this topic.
- How loud is the Kleinn RAMHD-734 really?
- The kit's Demon Model 730 horns carry a manufacturer rating of 157.8 dB at 150 PSI. Kleinn does not disclose the test distance, so treat the number as a brand claim rather than a field measurement — real-world readings at typical measuring distances will be lower.
- Which RAM trucks does the RAMHD-734 fit?
- Kleinn lists the kit for 2014-2026 RAM HD 2500 and 3500 trucks. It is not offered for RAM 1500 models, which use a different frame and have their own kit options.
- Do I need to drill or cut anything to install it?
- No, per Kleinn. The kit ships with vehicle-specific brackets and is advertised as a 100% bolt-on install with no drilling, cutting, or welding. You still need to run wiring to the battery and route airlines, so plan on a full day for a careful first install.
- What's the difference between the Model 730 and Model 230 versions of this kit?
- The $1,599.95 Model 730 version reviewed here uses stainless Demon 730 horns, the 200 PSI waterproof 6450RC compressor, and 1/2-inch airline. The Model 230 version substitutes ABS Beast horns, the 150 PSI 6350RC compressor, and 1/4-inch airline.
- Can the RAMHD-734 air up tires too?
- Yes. It is a full onboard air system: Kleinn rates it for tires up to 39 inches and includes a 24-ft quick-connect hose, a luminescent tire inflator gauge, and a coupler relocation kit.
