HX55 3536995 Turbocharger for Cummins M11 ISM | 3590044 New

HX55 3536995 Turbocharger for Cummins ISM M11

HX55

The HX55 is a Holset fixed-geometry turbocharger for the Cummins M11 and ISM 10.8L diesel engines. No variable vanes, no electronic actuator, no wastegate on this turbo - it is a straightforward mechanical unit that relies on exhaust energy alone to build boost. The HX55 has been in service since the late 1990s and remains one of the most common turbos on M11 and ISM-powered trucks and buses still on the road. Holset part 3536995 is the master number; the replacement assembly is 3590044. Our HX55 is built new with all new components - compressor wheel (62.9mm inducer / 97.8mm exducer), turbine wheel (86.4mm inducer), bearing housing, and both housings - dynamically balanced and shipped with gaskets. We supply shops, fleets, and distributors.

Turbo Model

HX55 (fixed geometry, non-wastegated)

OEM / Interchange Numbers

3536995, 3536996, 3590044, 3590045, 3800471, 3803938, 3536149, 4039173, 4046031, 2834419, 2834364

Application

Cummins ISM, ISME, M11 Truck and Bus, 1999-2012

Service & Support

1-Year Unlimited-Mileage Warranty
US Stock, Fast Dispatch
Bulk Orders Welcome
White-Label Support
Fully Certified

Get a Quick Quote

FAQ

The HX55 (3536995 / 3590044) fits the Cummins M11, ISM, and ISME 10.8L diesel engines used in trucks and buses from 1999-2012. It also fits some International trucks running the M11.

No. The HX55 is a fixed-geometry turbo with no wastegate, no VGT vanes, and no electronic actuator. Boost is controlled entirely by exhaust energy. Install is straightforward - bolt on, connect oil lines, start the engine. No calibration or wiring required.

Common signs: shaft play (radial wobble or axial drag), turbo whine or rattle at idle, oil in the intake boot or charge-air cooler, black or blue smoke under load, and loss of boost at rated power. Grab the compressor wheel and check for play before ordering.

Brand new, 100% new components, dynamically balanced. Ships with gaskets. No core charge. One-year unlimited-mileage warranty.

Holset numbers: 3536995, 3536996, 3590044, 3590045, 3536149, 4039173, 4046031, 2834419, 2834364. Cummins numbers: 3800471, 3803938. All cross-reference to the same HX55 assembly for M11/ISM.

Yes. US stock, volume pricing for shops, fleets, rebuilders, and distributors.

HX55 Turbo for Cummins M11 and ISM: A Reliable Workhorse

The Cummins M11 and ISM engines ran in tens of thousands of trucks, buses, and industrial machines from the mid-1990s through 2012. Many are still in daily service. The HX55 is the turbo that keeps them running. It is mechanically simple and durable, but after 300,000-600,000 miles, even a well-maintained HX55 will need replacing.

Key specifications

Spec	Value
Compressor wheel	62.9mm inducer / 97.8mm exducer
Compressor A/R	0.68
Turbine wheel	86.4mm inducer / 77.8mm exducer
Turbine A/R	0.88
Wastegate	None
VGT	No - fixed geometry
Cooling	Oil only
HP capability	370-500+ HP

What makes the HX55 different from VGT turbos

The HX55 is a fixed-geometry turbo with no electronic components. There is no actuator, no position sensor, no wiring harness, and no calibration step during install. Boost builds in direct proportion to exhaust energy and falls off with engine speed. This simplicity is actually a major selling point for older M11 and ISM trucks: fewer parts to fail, lower replacement cost, and a faster install. If your engine ran a VGT (HE400VG or HE451VE), this is not the right turbo - check the turbo nameplate to confirm.

Common failure modes

Bearing wear - the most frequent failure. Oil starvation from clogged feed lines or poor oil quality accelerates it. Symptoms: shaft play, turbo whine at idle, oil in the intake tract.
Compressor wheel erosion - dust ingestion from a leaking air filter or loose intake clamp. The large 97.8mm exducer wheel catches debris fast.
Turbine housing cracks - thermal cycling over hundreds of thousands of miles. Exhaust soot at the turbo flange and reduced boost are the signs.
Oil seal failure - restricted drain tube or high crankcase pressure pushes oil past the seals. Blue/white smoke and rising oil consumption.

Installation

Flush the oil feed line with solvent and blow it clear. Replace if internally coked.
Replace the oil drain gasket. Inspect the drain tube for carbon buildup or kinks.
Check the air filter, intake ducting, and charge-air cooler boots for leaks or debris.
Verify crankcase pressure is within spec.
Prime the new turbo with clean oil, hand-spin the shaft, crank without fuel for 15-20 seconds.
Idle 3-5 minutes before loading. No calibration needed - bolt on and go.

See our quality process for details.