1994 Am General Hummer Problems
Owner-reported complaints filed with NHTSA, grouped by component
Data refreshed
What this page shows
Everything below is an owner-reported complaint submitted to NHTSA about the 1994 Am General Hummer, grouped by the component NHTSA recorded on the report. These are not confirmed defects, and they are not recalls. NHTSA does not verify most reports before publishing them, and a category with more reports in it is not evidence that a part is defective.
Complaints are reports submitted by owners and drivers to NHTSA. They are not verified and do not establish that a defect exists.
Reports by component
Ranked by how many owner reports name each component category
- Body & structure114.3%
- Brakes114.3%
- Heating & air conditioning114.3%
- Interior & seats114.3%
- Powertrain (other)114.3%
- Transmission114.3%
- Visibility114.3%
Percentages are of component mentions. A single complaint can name more than one component, so these do not sum to the total complaint count.
Each component in detail
What the reports in each category say, in the owners' own words
Body & structure
Reports naming the vehicle structure, frame, body panels, doors, hood and trim.
From owner reports, verbatim
HEAT SHIELD RATTLES. MJS
Too few reports in this category for a page of its own — they appear in the full complaint list.
Brakes
Reports naming service brakes, the antilock braking system, brake hoses, master cylinders or the parking brake.
From owner reports, verbatim
HEAT SHIELD RATTLES. MJS
Too few reports in this category for a page of its own — they appear in the full complaint list.
Heating & air conditioning
Reports naming the heating, ventilation and air-conditioning system.
From owner reports, verbatim
HEAT SHIELD RATTLES. MJS
Too few reports in this category for a page of its own — they appear in the full complaint list.
Interior & seats
Reports naming seats, latches, locks, linkages and interior fittings.
From owner reports, verbatim
HEAT SHIELD RATTLES. MJS
Too few reports in this category for a page of its own — they appear in the full complaint list.
Powertrain (other)
Powertrain reports that are not specifically the engine or transmission — driveshafts, axles, transfer cases and differentials.
From owner reports, verbatim
HEAT SHIELD RATTLES. MJS
Too few reports in this category for a page of its own — they appear in the full complaint list.
Transmission
Reports naming the automatic or manual transmission, including shifting behaviour, shudder, slipping and transmission control modules.
From owner reports, verbatim
STRESS FRACTURES IN THE TRANSFER CASE ALUMINUM INTERCOOLER LOOP OF THE AUTOMATIC TRANSMISSION COOLING CIRCUIT CAUSED DESTRUCTION OF THE TRANSMISSION DUE TO LACK OF TRANSMISSION OIL. THIS SAME DEFECT HAS BEEN NOTED IN AT LEAST THREE AM GENERAL HUMMERS, AND A SUDDEN LOSS OF ATF FLUID MAY RESULT IN A CATASTROPHIC FAILURE OF THE TRANSMISSION AT SPEED, POSSIBLY CAUSING A CRASH. THE TRANSFER CASE INTERCOOLER LOOP IS INSIDE THE TRANSFER CASE OF THE HUMMER. TRANSMISSION FLUID FROM THE 4L80E AUTOMATIC TRANSMISSION CIRCULATES THROUGH THIS ALUMINUM FINNED COOLING LOOP AND TRANSFERS HEAT TO AND FROM THE TRANSFER CASE FLUID, WHICH IS PHYSICALLY ISOLATED FROM THE TRANSMISSION FLUID BY THE INTERCOOLER LOOP, TO THE TRANSMISSION FLUID, WHICH IS THEN CIRCULATED THROUGH THE TRANSMISSION OIL COOLER AT THE FRONT OF THE VEHICLE AND RETURNED TO THE TRANSMISSION. DUE TO IMPROPER DESIGN, THE INTERCOOLER LOOP MOVES AND VIBRATES INSIDE THE TRANSFER CASE AND OVER TIME DEVELOPS STRESS FRACTURES NEAR THE INPUT NIPPLE. THIS CAUSES ATF TO BE PUMPED FROM THE TRANSMISSION INTO THE TRANSFER CASE, AND FROM THERE INTO THE HUMMER VENT SYSTEM WHICH CONNECTS THE GEARED HUBS, DIFFERENTIALS AND AIR CLEANER. THERE IS USUALLY NO EXTERNAL INDICATION OF FLUID LOSS, AND EVENTUALLY, DEPENDING ON THE SEVERITY OF THE CRACKS, LOW ATF LEVELS CAUSE THE TRANSMISSION TO BE DESTROYED, POSSIBLY CATASTROPHICALLY, AND POSSIBLY AT HIGH SPEEDS, WHICH MAY POSE A SEVERE SAFETY HAZARD. IN MY CASE, I NOTICED A CLOUD OF WHITE SMOKE BEHIND MY VEHICLE AS I DROVE AT 75 MPH DOWN I-25 OUTSIDE DENVER. I WAS ABLE TO STOP BEFORE THE TRANSMISSION SEIZED, BUT THE ONLY REASON I NOTICED THE PROBLEM WAS BECAUSE A PLASTIC VENT LINE SOFTENED AND RUPTURED, SPILLING ATF ONTO THE EXHAUST PIPE...WHICH CREATED A SIGNIFICANT FIRE HAZARD. MY TRANSMISSION WAS DAMAGED AND HAD TO BE REPLACED AS A RESULT, AND THE CAUSE OF THE FAILURE WAS TRACED TO THE DEFECTIVE INTERCOOLER LOOP IN THE TRANSFER CASE. THIS INTERCOOLER LOOP FAILURE HAS BEEN EX
Too few reports in this category for a page of its own — they appear in the full complaint list.
Visibility
Reports naming windshields, glass, wipers, defrosters and mirrors.
From owner reports, verbatim
HEAT SHIELD RATTLES. MJS
Too few reports in this category for a page of its own — they appear in the full complaint list.
Higher-selling and older vehicles accumulate more reports. Counts are not failure rates and are not directly comparable between vehicles that sold in very different numbers.
Elsewhere on this vehicle
Data sources
- NHTSA Office of Defects Investigation — owner-reported complaints and the components recorded on them
Data on this page last refreshed .