Mustang Floor Pan Replacement: Cost And Process

Replacing the floor pans in a 1967 Mustang is a significant job and can be costly. The cost of the project will depend on the extent of the rust damage, with some estimates ranging from $500 to $5,500 for parts and labour. It is also possible to carry out the work yourself, which will significantly reduce costs, but it is a complex and time-consuming task that requires welding skills and knowledge of car restoration.

The first step is to assess the damage and decide on the scope of the project. If only one side of the floor pan needs to be replaced, it may be more cost-effective to opt for a partial replacement. However, a full floor pan replacement will result in a nicer finish and less welding work.

Before beginning the replacement, it is essential to remove the interior, including seats, carpet, shifter, rocker trim, fuel line, and drive shaft. This step can be done by the car owner to save on labour costs.

The next step is to remove the old floor pan and fit the new one. This process can be challenging, especially if the car has been poorly worked on in the past. It is crucial to take precise measurements and ensure that the new floor pan is correctly aligned and welded in place.

Finally, the interior of the car will need to be reinstalled. This process can be time-consuming, depending on the level of disassembly required.

Overall, replacing the floor pans in a 1967 Mustang is a significant undertaking that requires a good understanding of car restoration and welding techniques. While it is possible to complete the project oneself to save on labour costs, it is essential to have the necessary skills and equipment to ensure a successful outcome.

Full floor pan replacement vs. partials

When it comes to repairing the floor pans of your Mustang, there are two main options: full floor pan replacement or partial replacement. Here is a detailed comparison between the two to help you make an informed decision.

Full Floor Pan Replacement:

• Less work than doing partial replacements, as you don't need to weld the seams between multiple panels.
• Results in a cleaner and more presentable look, without the welded seams running parallel to the tunnel.
• Provides an opportunity to access and coat the inside of the frame rails, which can prevent future rust issues.
• Requires removing the interior and possibly taking the car to a shop, which can be inconvenient and add to the cost.
• Generally more expensive in terms of parts cost, but can save time and labour costs compared to partial replacements.

Partial Floor Pan Replacement:

• Can be a more cost-effective option if only a small area is affected by rust and you can perform the work yourself.
• May be a good choice if you only need to replace one side and want to avoid the complexity of installing a full pan.
• Requires more welding compared to full pan replacement, especially if you want to achieve a smooth and seamless finish.
• Can be more time-consuming, as you need to cut, weld, and finish multiple patch panels.
• May not be suitable if the rust has spread to multiple areas or if you want to ensure a high-quality installation.

In summary, full floor pan replacement is often recommended for its ease of installation, better appearance, and potential for long-term rust prevention. However, partial replacements can be a more affordable option for small repairs, especially if you have the skills and equipment to do it yourself. Ultimately, the decision should be based on the extent of the damage, your budget, and your personal preferences for the project.

Cost of replacement

The cost of replacing the floor pans in a 1967 Mustang varies depending on the extent of the damage, the condition of the car, the chosen repair method, and the labour rate of the chosen repair shop.

Full Floor Pan Replacement

For a full floor pan replacement, the parts alone can cost around $300 to $1000. This includes the cost of the new floor pan, as well as other necessary components such as torque boxes, toe boards, seat platforms, and welding equipment.

The labour cost for a full floor pan replacement can range from $1000 to $5500, depending on the complexity of the job and the labour rate of the chosen repair shop. Some owners choose to perform the replacement themselves to save on labour costs, but this requires a high level of skill and access to the necessary tools and equipment.

Partial Floor Pan Replacement

For a partial floor pan replacement, the parts cost can be significantly lower, depending on the extent of the damage and the specific components that need to be replaced.

The labour cost for a partial floor pan replacement will also be lower than a full replacement, but it can still be substantial, ranging from a few hundred to a couple of thousand dollars.

Additional Considerations

It is important to note that the cost of floor pan replacement can vary depending on the specific model and year of the Mustang, as well as the location of the repair shop. Additionally, there may be other related repairs that need to be addressed, such as rust repair or replacement of other damaged components.

When considering the cost of floor pan replacement, it is essential to obtain multiple quotes from reputable repair shops and to carefully evaluate the extent of the damage and the necessary repairs. It is also worth considering the long-term benefits of a proper repair, as a well-executed floor pan replacement can significantly improve the structural integrity and value of the vehicle.

Removing interior

Removing the interior of a 1967 Mustang is a necessary step to gain access to the floor pans for replacement. The process can vary depending on the specific model and condition of the vehicle, but here is a general guide on how to remove the interior of a 1967 Mustang:

Remove the Seats and Carpeting:

Start by removing the seats, which are typically held in place with bolts or brackets. Next, take out the carpeting and any insulation or sound deadening material underneath. This will expose the floor pans and provide access for replacement.

Disconnect Electrical Connections:

Before proceeding further, it is important to disconnect all electrical connections, such as those for the stereo system, interior lights, and any power windows or locks. Label and set aside these components to avoid confusion during reassembly.

Remove Door Panels and Interior Trim:

The door panels will need to be carefully removed, as they are often held in place with spring clips or other fasteners. Start by removing the armrests, door handles, and window cranks. Then, gently pry the door panels away from the doors, being careful not to damage the panels or the underlying structure. Similar procedures will apply to removing interior trim pieces, such as the rear quarter panels and any other decorative or functional components attached to the interior.

Disconnect Fuel Lines and Other Mechanical Components:

Depending on the extent of the floor pan replacement, you may need to disconnect fuel lines, brake lines, and other mechanical components that run through or near the floor pans. Always refer to a repair manual specific to your Mustang model for detailed instructions on disconnecting and reconnecting these components safely.

Remove Steering Wheel and Column (if necessary):

If the floor pan replacement requires access to the area behind the dashboard, it may be necessary to remove the steering wheel and column. This is a complex task, as it involves disconnecting various components and ensuring the vehicle is properly supported beforehand. Always consult a qualified mechanic or a repair manual for guidance.

It is important to note that the above steps provide a general overview of the process. Depending on your specific Mustang and the scope of the floor pan replacement, additional steps or variations may be required. Always refer to model-specific repair manuals and resources for detailed instructions tailored to your vehicle.

Repairing rust

Rust is a common problem for classic cars, and if left untreated, it can cause serious damage. The key to stopping rust is to address the issue as soon as possible. If you notice the first signs of rust on your Mustang, such as a bubble of paint or a small brown stain, it's important to take action to prevent it from spreading.

Assess the Damage:

Before beginning any repair work, it's important to assess the extent of the rust damage. Surface rust, which appears as small spots or stains, is relatively easy to fix. However, if the rust has permeated through the panels of the car, the repair process will be more complex and may require professional assistance.

Prepare the Car:

Park your Mustang in a warm, dry location to reduce exposure to moisture. Regularly start the engine and keep the car clean, using a mild, non-abrasive detergent. Open the doors after washing to allow for proper drainage. A regular wax and polish will also help protect the car from rust.

Remove the Rust:

For small areas of surface rust, use sandpaper to cut through the paint or rust until you reach the bright metal underneath. Apply an anti-rust solution to prevent further corrosion. If the rust has caused scale damage or holes/penetration, more extensive repair work is needed. Use a wire brush and a grinding wheel to remove the rust and smooth the surface. For holes or penetration, you may need to replace the affected parts or hire a welder to patch the panels.

Apply Primer and Paint:

Once the rust is removed and the surface is smooth, it's time to apply primer. Use thin coats, building up to 3 coats for a stronger base. Then, apply 3-4 thin coats of paint, allowing each coat to dry properly before applying the next. Finish with a coat of polish for added protection.

Seek Professional Help if Needed:

If the rust damage is extensive or you feel uncomfortable performing the repair yourself, don't hesitate to seek professional help. Contact a reputable auto body shop or a classic car restoration specialist for assistance.

As for the cost of repairing rust on your 1967 Mustang, prices can vary depending on the extent of the damage and the labor involved. Some forum users have reported quotes ranging from \$850 to \$5,500 for floor pan replacement, with the higher price including other metal work such as the firewall and fresh air intake system. Keep in mind that repairing rust as soon as it appears will likely be less costly than allowing it to spread and cause further damage.

Welding

First, you must assess the rust damage and remove the rusted floor pans. It is important to decide what gets removed and what stays. You can keep some of the good sheet metal to maintain the frame's stiffness. You should also test fit the floor pans to ensure a good fit. Once you are happy with the fit, clean and dress the areas with a wire wheel and grinder to remove old paint, rust, and dirt. Then, coat the areas with a cold galvanizing weld-through primer.

Now it's time to weld. If you are not a confident welder, it is recommended to get a professional to do the welding for you. If you choose to weld the floor pans yourself, you will need a few tools, including a welder (flux core or gas-shielded MIG preferred), grinder, cut-off wheel, spot-weld cutter or air-hammer with a spot-weld breaker, small body hammer, drill and bits, and clamps. A plasma torch will also speed up the process, but it is not necessary, as you can use a cut-off wheel instead.

When welding, it is important to use a stitch weld process for the perimeter of the pan, laying down a series of 1-inch-long beads a few inches apart. Warping is not much of a factor on a floor pan, but burning through the metal is, so the stitch makes it easy and clean. You should also use vice-grip clamps to squeeze the inner floor edge to the rocker panel.

Once the welding is completed, treat all of the seams and spot welds with a coating of seam sealer to protect them and seal off any leaks.

Frequently asked questions