What we cover
Hummer service scope by era and platform
Legacy Hummer H1, H2, and H3 (2003 to 2010)
Body-on-frame GM truck mechanics. The shop has worked on the gasoline shared platforms since they were new: 6.0L V8 on the H2 GMT820/830, Vortec 3.5L and 3.7L 5-cyl or 5.3L V8 on the H3 GMT345. The H1 with the 6.5L diesel V8 or 6.6L Duramax is a diesel, which we do not service; that work goes to a dedicated diesel specialist, and we will point you to one.
Common examples: Brakes, suspension, drivetrain, cooling, and electrical sized for a 7,000-lb truck, Rust mitigation: undercoating refresh, frame inspection, brake-line replacement before roadside failure, Off-road work: 2-inch leveling, 3-inch lifts with geometry correction, larger-diameter tire fitment, Pre-purchase inspection with documented frame and brake-line report
GMC Hummer EV pickup and Sierra EV (2022+)
The Hummer EV is a 9,000-lb truck with Ultium battery hardware and conventional vehicle systems wrapped around it. The conventional side is what stays here. Tooling includes safe high-voltage isolation procedures so a tech can pull the 12V battery or service a brake caliper without an HV incident.
Common examples: Tires, tire rotation, balance, and alignment on heavy-duty platform that wears tires fast, Brakes with attention to regen-biased rear pad wear, Suspension components, alignment, Adaptive Air Ride diagnostics, CrabWalk hardware in the loop, Cabin AC, 12V auxiliary battery, low-voltage thermal-management coolant service
Off-road and lift work on legacy Hummers
Standard jobs are routine: 2-inch leveling, 3-inch lifts with geometry correction, 35-inch tires on a stock H3. Custom 6-inch builds with linkage relocations and regear get an honest answer about whether the job belongs here or at a dedicated off-road shop.
Common examples: Extended sway-bar links for lifted trucks, Regear conversations for tire size, Skid-plate installation and rock-slider mounting, Post-trail inspections
Referred to the GMC dealer
A short list belongs at the GMC dealer. The front desk says which on the phone before any truck is driven over. That line stays in the same place every time, which is how an independent shop earns repeat Hummer EV owners.
Common examples: High-voltage Ultium battery pack diagnosis, replacement, and module work, Drive-unit inverter and electric motor work, DC fast-charge port and Onboard Charging Module, High-voltage thermal-management system and BMS software updates
Symptoms and what each one usually means
Match what your Hummer is doing to the right next step. Hummer issues progress slowly until they do not, and a 7,000- or 9,000-lb truck lengthens stopping distance when one component is weak.
Clunk over bumps on an H2 or H3
Ball joint, sway-bar end link, strut mount, or control-arm bushing. Common on H2 above 80,000 miles and on H3 above 60,000 miles. Suspension components on heavy trucks wear in pairs; the matched part on the same axle is often close behind.
Brake pulsation on a legacy Hummer
Warped rotor, stuck caliper, or pad transfer film on heavy hardware. Heavier truck, more rotor heat, more frequent symptom. The fix is conventional brake work sized for the platform.
Vibration at highway speed
Tire balance is the first suspect. Wheel bearing, driveshaft U-joint, and bent wheel are the next three. Heavy-duty platform loads bearings harder than a passenger car; check is non-negotiable.
Coolant or oil under the H2
Intake gasket on the 6.0L V8 is a known one. Water pump and timing-cover area are also common. Diagnosis on the lift identifies which and what else is downstream.
Hummer EV range dropping faster than expected
Tire pressure, alignment, dragging brake, or a degrading 12V auxiliary battery messing with system wake cycles. All four are conventional fixes that happen here without involving the HV side.
Hummer EV brake pulsation or grinding, especially rear
Regen-biased systems put a lot of stop-and-go load on the rear pads in city driving. Conventional brake diagnosis: eyes on the components, measurements on the pads and rotors.
Hummer EV air ride uneven or warning light
Compressor, sensor, or leak in an air line. Same diagnostic approach the shop uses on Mercedes air-ride, Lincoln Navigator, and RAM 1500 air-ride systems.
Hummer EV cabin AC slow to cool
Cabin compressor or refrigerant on the cabin loop, not the high-voltage thermal loop. Standard refrigerant service applies.
Two or more at once, do not wait. Heavy trucks lengthen stopping distance when one component is weak and let it overload the next.
Hummer service for Mays Landing and Atlantic County drivers
Same family, same eight bays, same corner of Mays Landing since 1981. Kneble's serves Hamilton Township, Egg Harbor Township, Northfield, Somers Point, Folsom, Buena Vista, and the rest of Atlantic County. Fred Kneble has been turning wrenches here for decades. Nancy Kneble runs the shop and the books. Foreign-and-domestic by design. State inspection and repair on site, which matters on the legacy Hummers because the inspection station and the repair shop are the same place. AAA Approved Auto Repair, which means we are independently audited on pricing and quality, not just self-graded.
Helpful details to mention
- Check engine light, with or without a noticeable change in how the truck performs
- Coolant loss on the 6.0L Vortec V8 (intake manifold gasket failure pattern)
- 4WD engagement fault from the transfer-case actuator (H2 known wear pattern)
Customer proof
Service was performed quickly and the Kneble Team provided great communication throughout the visit.Robert Orzechowski, Google review
Questions before scheduling?
Talk with us about Hummer Repair
Tell us what you drive, what you are noticing, and when you would like to come in. We will help you choose the right next step.
Service guide
Hummer Repair Service Guide
Use this guide to review service factors, related videos, local driving conditions, and questions to ask before scheduling service.
In this guide
01 of 04, What Hummer
What Hummer service costs and what affects it
A final price needs the truck on the lift. Anyone who quotes a sight-unseen Hummer job is either guessing low to get the truck in the door or quoting their highest-margin work regardless of what you actually need. The factors that push the estimate up or down can be discussed up front.
Read more about What Hummer service costs and what affects it
Era and platform
An H1 parts hunt looks nothing like an H3 parts hunt. The H1 was assembled by AM General and shares parts with commercial diesel trucks. The H2 shares its driveline with the GMT820/830-platform Silverado HD. The H3 shares its driveline with the GMT345-platform Colorado and Canyon. Each one is a different parts and labor conversation.
Salt-belt corrosion
Trucks that spend December through March in Atlantic County see road-salt corrosion that drier-climate vehicles do not. A March suspension job often takes longer than a July suspension job on the same Hummer because the bolts fight the tech coming out.
02 of 04, H1 vs
H1 vs H2 vs H3: what the differences mean for service
The three legacy generations share the Hummer name and very little else.
Read more about H1 vs H2 vs H3: what the differences mean for service
H1 (1992 to 2006 civilian, AM General build)
Commercial-truck DNA, often a diesel V8, military-spec components throughout. The H1 is the hardest of the three to source parts for, and the parts that exist are not cheap. Diesel-powered H1s are diesel vehicles, so engine, fuel, and emissions work goes to a dedicated diesel specialist. Body and frame work on a gas H1 is specialty work the shop does not pretend is routine.
H2 (2003 to 2009)
GM 6.0L V8, GMT820/830 platform shared with the Silverado HD. The most common Hummer the shop sees. Parts are available, the mechanical work is heavy-duty truck work the team has done for 30+ years on the platform's Silverado siblings.
H3 (2006 to 2010)
Smaller, GMT345 platform shared with the Colorado and Canyon. 3.5L or 3.7L Vortec 5-cylinder or 5.3L V8. Often used as a daily driver. The easiest of the three to maintain. Parts hunt is the most forgiving.
Tell us what changed, when it started, and what you drive. We can help decide whether to start with an inspection, alignment check, or related repair.
03 of 04, GMC Hummer
GMC Hummer EV maintenance scope and what stays at the dealer
The Hummer EV maintenance scope is wider than most owners assume and narrower in one specific area: the high-voltage system. Conventional vehicle work on a vehicle that happens to be electric stays here. The EV-specific tooling in use is for safe high-voltage isolation procedures so a technician can pull the 12V battery or service a brake caliper without an HV incident. ASE-certified technicians with HV safety training is the right combination.
Read more about GMC Hummer EV maintenance scope and what stays at the dealer
In scope
Brakes (pads, rotors, brake fluid flush). Tires (rotation, replacement, balance, alignment). Suspension components (air ride, control arms, links, sensors). Cabin AC and cabin air filter. 12V auxiliary battery. Low-voltage thermal-management loop coolant service. Wipers, lighting, glass, body and trim. Wheel bearings.
Out of scope
High-voltage Ultium battery pack diagnosis, replacement, and module work. Drive-unit inverter and electric motors. DC fast-charge port and Onboard Charging Module. High-voltage side of the thermal-management system. Battery Management System software updates. That work belongs at the GMC dealer. The shop is not equipped to do it, will not pretend to be, and will tell you so on the phone before you drive over.
04 of 04, How South
How South Jersey roads affect Hummers (both eras)
Atlantic County is harder on Hummers than most of the country, and the reasons stack.
Read more about How South Jersey roads affect Hummers (both eras)
Salt season and salt-air exposure
December through March, the brine attacks ball-joint boots, brake-line clusters, leaf-spring shackles, body mounts, and the H1's exposed frame components. Shore commutes into Ocean City, Sea Isle, Margate, Ventnor, or AC add ocean spray. Marina parking in Somers Point or Egg Harbor adds direct salt water in the air.
Pothole and causeway-sand season
Black Horse Pike between Mays Landing and Pleasantville. Route 40 east of the Hamilton Mall. The Atlantic City Expressway entrance ramp. These take out control arms and bend wheels every winter. A Hummer EV at 9,000 lbs hits a pothole harder than a Camry, and the components feel it. Drifting sand on the causeways pulls through the cabin filter aggressively; Hummer EV owners who commute to AC should plan on a cabin filter every 12,000 miles, not the manual's 24,000.
Call the shop or request an appointment and include the vehicle year, make, model, mileage, and symptoms.
FAQs
Hummer Repair FAQs
Do you work on Hummer H1?
Yes. The H1 is the hardest of the three Hummer generations to source parts for and the most labor-intensive to work on, and we are honest about that. Patient parts hunting plus the right approach to the body and frame work, and we can keep an H1 going. We will not pretend an H1 is a quick-turnaround job.
Will you service my GMC Hummer EV out of warranty?
Yes, for the maintenance scope: brakes, tires, suspension, cabin AC, 12V battery, fluids, body and trim. Once a Hummer EV is out of warranty, the dealer's edge on this work is gone, and our ASE-certified labor rate sits below the dealer's. For high-voltage work we still send you to the dealer.
What about the high-voltage battery on the Hummer EV?
The Ultium pack stays at the GMC dealer. So does the drive-unit inverter, the DC fast-charge port, and the BMS software side. Anyone telling you otherwise about a non-EV-certified shop is selling you something you do not want. The front desk says that on the phone before any truck is driven over.
Can you handle a lift kit on an H2 or H3?
Yes for the standard configurations. 2-inch leveling, 3-inch lift with the geometry correction an honest install requires, 35-inch tires on a stock H3 with the right wheel spec. For custom heavy lifts with linkage relocations or regear, you get an up-front answer about whether the job is one we want to take or one that belongs at a dedicated off-road shop.
How is the rust on my H2 frame, and what can be done?
That answer comes off the lift, not off the phone. Frame and underbody condition get documented on every service visit, and on a pre-purchase inspection the report is the headline. If the frame is solid, treatment options follow. If the frame is gone, you get that news plainly so you can make an informed decision about the truck.
The brakes on my Hummer EV are squealing already. Is that normal?
Sometimes, sometimes not. Regen-biased systems put unusual wear patterns on pads. Glazed pads or a stuck caliper can also be the cause. The diagnosis is the same as on any other vehicle: on the lift, eyes on the components, measurements on the pads and rotors. The repair is conventional brake work.
Can you do a pre-purchase inspection on a used H3?
Yes. On a used H3, the frame and brake-line condition, the differential and transfer-case service history, and the alignment and tire-wear pattern tell most of the story. The written report goes home with you whether you buy the truck or not.
Will my NJ state inspection be a problem on a lifted H2?
Depends on the lift height, tire size, and headlight aim after the lift. NJ has rules. Kneble's is an NJ State Inspection Center, which means trucks get inspected here and the team knows what passes and what does not. A planned build can usually get a pass-or-fail read over the phone, and after the lift the headlights get re-aimed so the inspection goes smoothly.
Further information
Learn more about Hummer Repair
Use these related articles and videos to compare symptoms, maintenance timing, warning signs, and questions to ask before scheduling service.
Local shop
Visit Kneble's in Mays Landing
5473 Somers Point Road, Mays Landing, NJ 08330
Kneble's Auto Service Center is located at 5473 Somers Point Road, Mays Landing, NJ 08330 and serves drivers throughout Atlantic County and South Jersey.
- Mon to Fri 8am to 5pm
- Saturday 8am to 4pm
- Sunday Closed
Reviews
Trusted by South Jersey drivers
Customers come to Kneble's for clear communication, practical recommendations, and repairs handled by a local team they can reach directly.
Friendly receptionist. In and out within 45 mins.
Janet Jackson, Google review
Service was performed quickly and the Kneble Team provided great communication throughout the visit.
Robert Orzechowski, Google review
Excellent quick service by personable staff and very qualified techs at a reasonable charge.
Glenn Peterson, Google review
Very good service here. Treated us very well. Great conversation with Carmen.
Gary Mazzone, Google review