Moving to 35- or 37-inch tires can improve ground clearance, traction and off-road capability—but it can also create a problem at the back of your truck or Jeep. A matching full-size spare may no longer fit in the original location, and the added wheel-and-tire weight may exceed what the factory carrier, tailgate or mounting hardware was designed to support.
Why Your Spare Tire Should Normally Match Your Installed Tires
A spare tire is not much help on a remote trail if it is dramatically smaller than the other tires on the vehicle. Once a truck or Jeep is upgraded from its factory tire size to 35- or 37-inch tires, the original spare may have a meaningfully smaller rolling diameter.
When tires have different overall diameters, they travel different distances with each revolution. On a driven axle, that difference can make the differential continuously compensate as though the vehicle were turning. On some four-wheel-drive and all-wheel-drive systems, a substantial difference can also create unwanted load or heat in drivetrain components.
A smaller spare may be acceptable as a restricted temporary solution when the vehicle manufacturer specifically permits it, but it should not automatically be treated as suitable for regular trail use. Always follow the vehicle owner’s manual regarding spare-tire placement, four-wheel-drive operation, maximum speed and maximum travel distance.
Do you need the exact same wheel and tire?
The ideal off-road spare uses the same tire model, size, load type and similar wheel specifications as the four tires on the ground. That gives the most predictable clearance and handling and may allow the spare to be included in a five-tire rotation.
At minimum, confirm that the spare’s actual diameter is compatible with the vehicle, the wheel has the correct bolt pattern, and the wheel clears the brake components. Offset, backspacing, centre bore, lug-seat style and wheel-load rating may also matter.
Browse matching off-road tires and truck wheels when assembling a full-size spare package.
Oversized Spare-Tire Mounting Options Compared
| Mounting location | Best for | Main advantages | Main trade-offs |
|---|---|---|---|
| Factory under-bed location | Mildly oversized truck tires that still fit correctly | Preserves cargo space, low centre of gravity, factory-style appearance | Can reduce ground clearance, may not fit 35- or 37-inch tires, harder to access when stuck |
| Truck-bed carrier | Pickups, prerunners, trail trucks and simple builds | Strong, accessible, adaptable and generally cost-effective | Consumes bed space and may interfere with cargo or a tonneau cover |
| Swing-out bumper carrier | Overland trucks, SUVs and builds that need the bed or cargo area | Moves the spare off the body, keeps cargo space available, can carry accessories | Adds rear weight, cost and length; must be opened for cargo access |
| Reinforced Jeep tailgate carrier | Wranglers and similar rear-gate vehicles | Convenient single-door operation and familiar spare location | Requires carrier and hinge capacity appropriate for the complete assembly |
| Interior cargo mounting | Competition vehicles or builds prioritizing departure angle | Protected from obstacles and theft; weight remains inside the body | Consumes interior space and must be extremely well secured |
Option 1: Keeping the Spare in the Factory Under-Bed Location
Many pickup trucks carry the spare horizontally beneath the bed. This is a clean and space-efficient arrangement because it leaves the cargo box open and keeps the tire relatively low on the vehicle.
The limitation is physical space. A larger tire may contact the hitch, exhaust, differential, heat shielding, bed structure or rear bumper. Even when the winch cable can pull the tire upward, that does not prove that the tire is properly seated or protected from movement.
Ground-clearance and departure-angle concerns
An oversized under-bed spare may hang lower than the differential, hitch or bumper. This can become a problem when the truck drops off a ledge, crosses a deep rut or climbs a steep obstacle. The tire may drag, reduce the effective departure angle or become wedged against terrain.
The factory location can also be inconvenient when the truck is buried in mud, sitting in snow or positioned against an obstacle. Reaching beneath the vehicle to lower the spare may be far more difficult than accessing a bed- or bumper-mounted tire.
Best when the larger tire still fits exactly as intended
Retain the original location only when the full-size spare can be raised fully against its support, secured without movement, kept away from hot or moving components and carried without unacceptable ground-clearance loss. Never force a tire into a space that is too small or rely on partial engagement of the factory retaining mechanism.
Option 2: Mounting the Spare in the Truck Bed
A truck-bed spare-tire carrier is one of the most practical answers to the question, “Where should I mount a 35-inch spare tire?” It removes the tire from the vulnerable under-bed location and places it where it can be inspected, secured and accessed more easily.
Bed mounts are available in vehicle-specific and universal designs. Some use a central post, some position the tire against a bed side, and others integrate into a bed rack or cargo-management system. Installation requirements vary, and many heavy-duty designs require drilling through the bed.
Shop vehicle-compatible oversized spare-tire carriers and review every product’s maximum tire diameter, tire width, wheel-offset range and installation instructions before ordering.
Preserves more floor length
A vertical carrier positions the tire upright, often near the front or side of the bed. It can leave more usable floor length for coolers, tools or storage boxes, but the tire may rise above the bed rails and affect rearward visibility.
The mount must prevent the tire from rocking laterally. The bracket, wheel studs and bed attachment points all need to withstand repeated off-road impacts.
Popular for prerunner-style builds
An angled mount can lower the upper edge of the tire and create a recognizable off-road appearance. Depending on its location, it may also make the wheel easier to lift onto the carrier.
The trade-off is a larger footprint across the bed floor. The angled tire can make it harder to carry long cargo and may divide the remaining storage area into awkward spaces.
How much bed space will you lose?
A 35- or 37-inch tire occupies a substantial amount of room, especially when mounted diagonally. Before choosing a bed carrier, consider how the truck is normally loaded. A spare that works perfectly in an empty bed may interfere with toolboxes, camping equipment, recovery gear, motorcycles, an auxiliary fuel tank or a tonneau cover.
Storage can often be reorganized around the spare with properly secured truck boxes and storage systems. Confirm that drawers and lids can still open and that the tire does not block access to essential recovery equipment.
Option 3: Using a Swing-Out Bumper Tire Carrier
A swing-out carrier supports the spare from the rear bumper rather than the tailgate or cargo bed. It is a popular choice for overland trucks, Jeeps and SUVs because it preserves interior or bed space while keeping the spare accessible.
Some systems are built into a complete replacement bumper. Others use a carrier arm that is specifically designed to work with a compatible bumper. The spindle, bearings, latch, frame brackets and bumper structure must all be engineered for the spare’s weight and the dynamic forces created on rough roads.
Explore off-road bumpers and bumper accessories for vehicle-specific carrier and relocation components.
Advantages of a bumper-mounted carrier
- Keeps the pickup bed or SUV cargo area available.
- Transfers the spare-tire load away from a factory tailgate skin or light-duty carrier.
- Can improve access compared with an under-bed spare.
- May provide mounting points for a jack, recovery boards or fluid containers.
- Can accommodate larger tires when the system is rated and configured correctly.
Trade-offs to understand
- The bumper and carrier add weight behind the rear axle.
- The carrier must usually be unlatched and swung away before opening the tailgate or hatch.
- A large tire may partially block the rear window or backup camera.
- The assembly can increase overall vehicle length.
- Poorly adjusted latches or worn pivots may create movement or noise.
- The spare’s position can affect the departure angle even when it is higher than an under-bed tire.
Carrier and bumper compatibility matters
Do not assume a swing arm from one bumper system will safely fit another bumper. Tire-carrier arms, spindles and latches are structural components. Use only combinations explicitly approved by the manufacturer, and verify the maximum permitted tire size and wheel-and-tire weight.
Option 4: Upgrading a Jeep Tailgate Tire Carrier
Jeep Wranglers commonly carry the spare on the rear tailgate. This is convenient because the spare and tailgate can open together, but adding a large off-road tire and heavier wheel changes the load placed on the carrier, hinges and surrounding body structure.
A relocation bracket may move the spare upward or outward to clear the bumper, but relocation alone does not necessarily increase the tailgate’s weight capacity. A complete heavy-duty solution may include reinforced hinges, a strengthened carrier, adjustable wheel support and hardware designed to spread the load over stronger mounting locations.
Tailgate hinge and sheet-metal stress
The complete assembly acts like a lever. Increasing tire diameter can position more mass farther from the tailgate, which increases leverage on the hinge and carrier. Rough roads add repeated vertical, lateral and fore-aft impacts.
Possible symptoms of an overloaded or unsupported setup include tailgate sag, latch misalignment, rattling, cracked brackets, elongated mounting holes and difficulty opening or closing the gate. These symptoms should not be ignored.
Support the tire—not just the mounting studs
The spare should sit firmly against the carrier’s support points or isolators where the design calls for them. A tire suspended away from the carrier can place unnecessary bending load on the wheel studs and bracket. Adjustable carriers help position different wheel offsets so the tire remains properly supported.
Use the complete system required for your tire size
Check whether the manufacturer’s published capacity applies to the carrier by itself or only when it is combined with a hinge-reinforcement kit, adjustable spare mount or compatible bumper. A system advertised for a particular diameter may still have a separate maximum weight limit.
A 35- or 37-Inch Spare Can Be Heavier Than You Expect
Tire diameter is only one part of the load calculation. Construction, load range, tread depth, sidewall design and wheel material can make two same-size combinations weigh very different amounts.
A heavy-duty mud-terrain tire on a steel wheel can be considerably heavier than a lighter all-terrain tire on an alloy wheel. Accessories mounted to the same carrier—such as a jack, fuel container, recovery boards or trash bag—add more load and leverage.
Use the tire manufacturer’s listed weight and the wheel manufacturer’s listed weight whenever available. Add the weight of the centre cap, mounting adapters, locks and carrier-mounted accessories. Compare that total against the carrier manufacturer’s limit rather than estimating by tire diameter alone.
How Spare-Tire Location Affects Vehicle Capability
Ground clearance
An under-bed tire is vulnerable when it hangs below surrounding components. Moving it into the bed or onto a higher bumper carrier can improve clearance beneath the rear of the vehicle.
Departure angle
A rear-mounted spare may sit higher than an under-bed tire but farther behind the axle. The lowest and rearmost portions of the bumper, hitch, carrier and tire determine whether the rear of the vehicle will contact an obstacle.
Weight distribution
A bed-mounted spare positioned near the cab keeps the weight farther forward than a bumper carrier. A swing-out system places the tire behind the rear axle and adds the weight of the bumper and carrier itself. This may affect rear ride height, handling and available payload.
Visibility
A large vertical tire can reduce the view through the rear window. Check the driver’s sightlines and confirm that the spare does not create an unsafe blind area.
Accessibility
Think about the worst-case situation rather than only normal parking-lot access. Can the spare be removed when the bed is full, the vehicle is on an incline or the rear bumper is close to a tree? Can one person safely lift the assembly off the carrier?
Camera, Sensor, Brake-Light and Licence-Plate Relocation
Late-model trucks and Jeeps may have a rearview camera, parking sensors, blind-spot components, a centre high-mounted brake light or licence-plate lighting positioned near the original spare or bumper.
A larger tire can block the camera’s field of view or conceal the third brake light. A replacement bumper may change parking-sensor angles, and a swing-out carrier can cover the original licence-plate location.
Before installing a carrier, determine whether the system includes or requires:
- A rear-camera relocation bracket.
- An adjustable camera mount for different wheel offsets.
- A third-brake-light relocation bracket.
- A licence-plate bracket and working plate light.
- Extensions or retainers for factory wiring.
- Compatible parking-sensor mounts.
- A way to protect wiring as the carrier swings open.
Test every electronic feature after installation
Confirm that the camera image is centred, sensors operate normally, the plate is visible and illuminated, and the third brake light remains unobstructed. Wiring should have enough controlled movement for the carrier to open without stretching, pinching or rubbing.
Wheel Bolt Pattern and Mounting Hardware Must Match
The spare wheel must fit both the vehicle and the tire carrier. This begins with the bolt pattern, but several additional dimensions can affect compatibility.
Verify all of the following:
- Wheel bolt pattern
- Number of carrier studs
- Stud diameter and thread pitch
- Wheel centre-bore clearance
- Lug-nut seat type
- Wheel offset and backspacing
- Brake-caliper clearance
- Carrier adjustment range
- Tire width and sidewall clearance
- Wheel-and-tire weight limit
Do not redrill a carrier plate or substitute random hardware unless the manufacturer explicitly approves the modification. Use the required grade, thread engagement and locking method. Recheck torque after the initial installation period and as part of regular trail inspections.
Securing an Oversized Spare for Off-Road Impacts
A carrier must control the wheel-and-tire assembly in every direction. Static weight is only the beginning; potholes, washboard roads, whoops and ledges repeatedly accelerate the spare against its mounting points.
Confirm the carrier’s published limits
Check maximum tire diameter, width and total wheel-and-tire weight. Include any accessories mounted to the same arm or bracket.
Inspect the attachment structure
Bed mounts should use the specified backing plates or reinforced mounting points. Bumper carriers must attach to the bumper and frame exactly as instructed. Tailgate systems should include all required hinge reinforcement.
Position the tire against its supports
Adjust the carrier so the tire does not bounce on the studs. Install rubber isolators, bump stops or wheel supports where the design requires them.
Use compatible retention hardware
Install the correct lug nuts, retainers and locks. Ensure there is adequate thread engagement and tighten the hardware to the carrier manufacturer’s specification.
Inspect it regularly
Look for loose fasteners, cracked welds, latch movement, worn bushings, corrosion, damaged studs and contact marks. Reinspect after hard trail use or a significant impact.
Which Oversized Spare-Tire Location Is Best for Your Build?
| Your priority | Recommended starting point | What to verify |
|---|---|---|
| Keep the truck bed completely open | Swing-out bumper carrier | Bumper compatibility, carrier capacity, rear weight and sensor relocation |
| Simple installation and easy access | Truck-bed carrier | Bed drilling, backing plates, tonneau-cover clearance and cargo layout |
| Keep a factory appearance | Factory under-bed location | True clearance, secure seating, heat clearance and departure angle |
| Carry a larger Jeep spare on the tailgate | Reinforced hinge-and-carrier system | Total weight, bumper clearance, camera position and complete-system requirements |
| Maximize rear departure angle | Bed or interior mount | Cargo-space loss, visibility and secure structural mounting |
| Carry tools and overland accessories too | Rated bumper or modular bed system | Combined accessory weight and effect on payload |
There is no universal best location. A daily-driven pickup that regularly carries building materials may benefit from a bumper carrier, while a recreational truck with an open bed may be better served by a simple vertical mount. A Jeep owner who wants one-handed tailgate access may prefer a reinforced hinge-mounted system.
The correct decision is the one that safely supports the complete spare, preserves the vehicle functions you rely on and remains accessible when the vehicle is fully loaded or positioned on a trail.
Build a Complete Oversized Spare-Tire Setup
Off-Road Canada carries spare-tire carriers, bumpers, bumper accessories, truck storage, wheels and tires for off-road and overland builds. Always confirm the exact vehicle, wheel specifications, measured tire dimensions and carrier capacity before ordering.
Frequently Asked Questions
Where should I mount a 35-inch spare tire?
On a pickup, a truck-bed carrier is often the simplest solution if the tire no longer fits securely underneath the bed. A swing-out bumper carrier is a better starting point when preserving cargo space is important. Jeeps may use a reinforced tailgate carrier that is rated for the complete wheel-and-tire weight.
Can I use my smaller factory spare with 35-inch tires?
A substantially smaller spare should generally be treated only as a restricted emergency solution when the vehicle manufacturer permits it. Different tire diameters can affect handling and make drivetrain components compensate for different wheel speeds, particularly on 4WD and AWD vehicles. Check the owner’s manual before use.
Will a 35-inch tire fit in the factory under-bed spare location?
It depends on the truck, hitch, exhaust routing, bumper and the tire’s actual measured dimensions. Even when the tire can be raised into place, confirm that it seats securely and does not reduce ground clearance excessively or contact nearby components.
Is a bed-mounted or bumper-mounted spare better?
A bed mount is generally simpler, lighter and less expensive, but it consumes cargo space. A bumper-mounted swing-out preserves the bed and can support additional accessories, but it adds cost and weight behind the rear axle and must be opened to access the rear of the vehicle.
Do I need a reinforced Jeep tire carrier for 35-inch tires?
Reinforcement requirements depend on the Jeep model, wheel-and-tire weight, carrier design and manufacturer limits. A relocation bracket that creates clearance does not automatically strengthen the tailgate. Verify whether a reinforced hinge, heavy-duty carrier or complete matched system is required.
Can an oversized spare damage a Jeep tailgate?
An assembly that exceeds the factory carrier or hinge capacity can contribute to sag, rattling, latch misalignment and mounting-point stress. The risk increases when a heavier tire is positioned farther from the tailgate or driven repeatedly over rough terrain.
Does the spare wheel need the same bolt pattern?
Yes. The spare must fit the vehicle hub and the carrier studs. Also verify centre bore, lug-seat type, thread pitch, brake clearance, offset, backspacing and wheel-load rating.
Can a tire carrier block the backup camera?
Yes. A larger tire or different wheel offset can block or change the camera view. Some carriers include an adjustable camera mount, while others require a separate relocation bracket. Licence-plate and third-brake-light relocation may also be needed.
Should I include the full-size spare in tire rotations?
A five-tire rotation may help keep a matching full-size spare closer in tread depth to the other tires when the tire type, size and rotation pattern permit it. Follow the vehicle and tire manufacturers’ rotation instructions, especially for directional tires or staggered wheel setups.
Find the Right Spare-Tire Carrier for Your Truck or Jeep
Start with your year, make and model, then confirm the spare’s measured diameter, width, wheel specifications and total weight. Choosing a carrier by appearance alone can lead to clearance, capacity or compatibility problems.
Browse Tire CarriersThis guide provides general educational information. Tire mixing, temporary-spare use, carrier capacity, vehicle payload and installation requirements vary by application. Follow the vehicle, tire, wheel, bumper and carrier manufacturers’ current instructions and load limits. Professional installation may be appropriate where drilling, structural bumper installation, wiring relocation or tailgate reinforcement is required.
```