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Yes, Auto‑jet supplies replacement coolant tubes for Thomas Built and Freightliner school buses, matched by engine and OE number. Coolant tubes route engine coolant on rear-engine and conventional chassis, and the correct tube depends on the engine (Cummins ISC/ISB, Caterpillar C-7) and the OE number on the original tube. Match by the number stamped on the old tube. What to Confirm Before Ordering a Coolant Tube Coolant tubes are engine-specific and position-specific (upper,

Yes, Auto‑jet supplies exhaust parts built for the propane and gasoline versions of the Blue Bird Vision, including Ford V10 and Cummins configurations. The propane and gas exhaust routing differs from the diesel layout, so the correct tailpipe, over-axle pipe, muffler, or hanger depends on the model year, engine, and suspension. Match by the OE number on the original part. What to Confirm Before Ordering The propane and gasoline Vision changed exhaust configuration across mo

OEM-to-Auto‑jet part cross‑reference for Thomas Built school bus chassis, sampled by engine. Auto‑jet manufactures aftermarket replacement exhaust parts referenced here by OEM part number for identification and fitment purposes only. Auto‑jet is not affiliated with, sponsored by, or endorsed by any OEM or bus manufacturer named on this page. Call to confirm fitment before ordering. This page shows a representative sample by engine, not the full catalog. The complete verified

OEM-to-Auto‑jet part cross‑reference for Freightliner school bus chassis, sampled by engine. Auto‑jet manufactures aftermarket replacement exhaust parts referenced here by OEM part number for identification and fitment purposes only. Auto‑jet is not affiliated with, sponsored by, or endorsed by any OEM or bus manufacturer named on this page. Call to confirm fitment before ordering. This page shows a representative sample by engine, not the full catalog. The complete verified

OEM-to-Auto‑jet part cross‑reference for Blue Bird school buses, sampled by engine make and model. Auto‑jet manufactures aftermarket replacement exhaust parts referenced here by OEM part number for identification and fitment purposes only. Auto‑jet is not affiliated with, sponsored by, or endorsed by any OEM or bus manufacturer named on this page. Call to confirm fitment before ordering. This page shows a representative sample by engine, not the full catalog. The complete ver

IC Bus school bus exhaust fitment is set by engine, not by chassis badge. The same IC Bus body has carried Navistar's DT466 and VT365, the older T444E, the emissions-era MaxxForce line, and the current IC Gas 8.8L gas and propane engine, and the exhaust and aftertreatment parts change with each one. Matching the OE number off the failed part is faster and more reliable than matching a chassis name. Why Engine Determines IC Bus Exhaust Fitment IC Bus has run four distinct engi

School bus exhaust clamps are the most frequently reused component in exhaust repair, and the most frequently blamed when a repair leaks. Most clamp failures are a size mismatch or an undertorqued connection - not a defective part. School Bus Exhaust Clamps: U-Bolt vs. Seal Clamp Selection Both types are used on school bus exhaust, but they serve different applications. Using the wrong type at a given joint is how a repeat failure occurs. U-bolt clamp: cinches a joint by pull

An offset exhaust pipe routes the tailpipe or over-axle pipe away from a straight line to clear a frame rail, axle, or body mount that a straight pipe cannot pass. Offset pipes are not interchangeable across bus makes, since the offset angle, length, and flange position are chassis-specific. This school bus offset pipe guide covers confirmed fitment for Freightliner and Thomas Built, with OE cross-references so you can match by the number stamped on the old pipe. What Is an O

Sustained summer heat pushes school bus cooling systems past their design limits. School bus cooling system failure peaks in the first heat wave of summer service, when components that ran fine through the school year finally give out. The two parts that fail most often, charge air coolers and radiators, give specific warning signs before they go. This post covers the symptoms, the replacement criteria, and how to confirm fitment before ordering. For the winter half of this s

A Blue Bird school bus fuel tank is identified by its OEM number, not by year or model. Two buses that look identical can take different tanks, and a tank that bolts up on one chassis can sit wrong on the next. The OEM number is the one piece of information that confirms the right Blue Bird school bus fuel tank before ordering. For inspection criteria on a tank that may be failing, see the fuel tank inspection guide. Why the OEM Number Matters More Than the Model Year Blue Bi

Auto‑jet has been manufacturing school bus exhaust parts in Clive since 1959. Not reselling. Building. That's why the catalog still reaches the older Blue Bird, IC Bus, Thomas Built, and Freightliner configurations distributors stopped stocking years ago, and why fleets calling for a hard-to-find part usually hear "in stock" instead of "backordered." President John Rapp joined Leisa Fox on the Made in Iowa podcast to talk about how Auto‑jet has built and held that model throu

In late June 2026, two business leaders from Principal Financial Group, Amy Friedrich and Nate Schelhaas, toured Auto‑jet Muffler Corporation's manufacturing plant in Clive, Iowa. The visit covered how the company plans production capacity, sources its material, and manufactures finished exhaust components. Auto‑jet manufactures exhaust systems and components for school-bus and heavy-duty applications. The steel used in production is sourced domestically. In a public post fol

Auto-jet president John Rapp joins the Iowa Manufacturing Podcast to talk about building a manufacturing business in Clive, Iowa.

Yes, US-market school buses use catalytic converters as part of the emissions system, and the right replacement depends on the bus make, engine, and model year, not just on what the old one looks like. This school bus catalytic converter guide covers fitment for Blue Bird, IC Bus, Ford Type A, and Thomas Built, with OE cross-references so you can match by the number stamped on the old unit. Do School Buses Have Catalytic Converters? Yes. Gasoline, propane, and many diesel sch

Band clamps seal the slip joints on school bus exhaust systems. When sized and installed correctly, a band clamp creates a leak-free connection between two pipe sections that holds under vibration, thermal cycling, and road salt exposure. When the wrong size or type goes in, the joint leaks at first startup or fails within weeks. This page covers how to size, select, and install the band clamps Auto‑jet stocks for school bus exhaust. The same part is called a band clamp by mo

IC Bus MaxxForce EGR problems are the most consistent maintenance issue on IC Bus school buses with MaxxForce DT engines. The EGR cooler and EGR valve both fail at higher rates on school bus duty cycles than on over-the-road trucks, and the failure modes are different. Confusing one for the other means replacing the wrong component. IC Bus MaxxForce EGR Problems: Cooler Failure vs. Valve Failure These are two distinct failure modes with different causes, different symptoms, a

School bus charge air cooler failure is a gradual power-loss problem that does not generate an obvious fault code in early stages. By the time a failing charge air cooler is causing noticeable symptoms, it has typically been leaking for some time. Knowing the symptoms and how to test for it gets the diagnosis right the first time and avoids replacing the wrong component. What Causes School Bus Charge Air Cooler Failure The charge air cooler cools compressed air from the turbo

IC Bus school bus exhaust parts require chassis series and engine confirmation before ordering. The CE Series and RE Series are different chassis with different exhaust routing, and the MaxxForce engine family has specific EGR components that fail regularly on school bus duty cycles. Which IC Bus School Bus Exhaust Parts Fit CE Series vs. RE Series? CE Series and RE Series are two fundamentally different chassis. CE and RE exhaust parts are not interchangeable. Confirm chassi

School bus radiator replacement becomes the right call when repair stops being cost-effective, or stops holding. Knowing the difference between a one-time fixable failure and a radiator past the repair threshold saves your shop from doing the same job twice. School Bus Radiator Replacement vs. Repair: How to Decide The distinction matters because a repair on a core that is systemically failing is a temporary fix that will come back inside the same season. Auto‑jet Part # Fits

Thomas Built school bus exhaust parts require model confirmation before ordering - not just engine, not just year. The Saf-T-Liner HDX and C2 do not share exhaust components even on identical engines. The MVP series uses its own configuration entirely. Ordering without the model designation produces fitment errors every time. Why Thomas Built School Bus Exhaust Parts Require Model Confirmation First Chassis geometry determines exhaust routing, not engine configuration. The HD