Nissan Altima Caliper Bracket Bolt Size

So, you're diving into a brake job on your Nissan Altima and need to know the caliper bracket bolt size? You've come to the right place. Getting this crucial specification right is essential for safety and proper brake function. Using the wrong bolt can lead to serious issues, including brake failure. This article will provide you with the information you need regarding the correct caliper bracket bolt size for your Altima, along with some helpful tips and considerations.

Understanding Caliper Brackets and Bolts

Before we dive into the specifics, let's quickly review the role of the caliper bracket and its bolts. The caliper bracket is a metal component that securely mounts the brake caliper to the steering knuckle or hub assembly. It provides a stable platform for the caliper, ensuring it remains properly positioned over the brake rotor. The caliper bracket bolts are responsible for attaching the bracket to the vehicle.

These bolts are subject to significant stress during braking. The force generated when the brake pads clamp down on the rotor is transferred through the caliper and into the bracket. Therefore, the bolts must be strong enough to withstand these forces without failing. That's why using the correct size, grade, and torque specifications is absolutely critical.

Why Bolt Size Matters

Using the wrong size or type of bolt can have several negative consequences:

Insufficient Clamping Force: A bolt that is too small in diameter may not provide enough clamping force to hold the bracket securely. This can lead to movement, vibration, and premature wear of the brake components.

Thread Damage: Using a bolt with the wrong thread pitch or diameter can damage the threads in the steering knuckle or caliper bracket. This can make it difficult or impossible to properly tighten the bolt.

Bolt Failure: If the bolt is not strong enough to withstand the braking forces, it can shear or break. This can result in complete brake failure, which is extremely dangerous.

Improper Caliper Alignment: Incorrect bolts may not position the caliper correctly, leading to uneven pad wear and reduced braking performance.

Nissan Altima Caliper Bracket Bolt Size: A Model-Year Breakdown

The specific caliper bracket bolt size can vary depending on the year and trim of your Nissan Altima. It's always recommended to consult your vehicle's repair manual or a trusted parts catalog to confirm the correct size for your specific application. However, I can provide some general guidelines.

3rd Generation (2002-2006) Altima

For the 2002-2006 Altima, commonly referred to as the L31 platform, the front caliper bracket bolts are typically M12 x 1.25 x 35mm. This means:

M12: The bolt has a metric diameter of 12 millimeters.

1.25: The thread pitch is 1.25 millimeters (the distance between threads).

35mm: The bolt's shank length is 35 millimeters.

The rear caliper bracket bolts for these models are often a similar size, typically also M12 x 1.25, but the length might vary slightly (often around 30-35mm). Again, always confirm with your vehicle's specific information.

4th Generation (2007-2012) Altima

The 2007-2012 Altima, designated the L32 platform, generally uses the same size bolts for the front caliper bracket as the previous generation: M12 x 1.25 x 35mm. Again, double-check for your specific year and trim. Rear bolts tend to follow a similar pattern as well, often being an M12 bolt with a similar pitch.

5th Generation (2013-2018) Altima

The 2013-2018 Altima (L33) continues with the trend of using M12 x 1.25 bolts for both front and rear caliper brackets. Lengths will vary based on whether you are working on the front or rear. Always verify the length.

6th Generation (2019-Present) Altima

The current generation Altima (L34) maintains the use of metric bolts, and it's highly likely that M12 x 1.25 bolts are still employed. However, due to subtle changes in design, it is even *more* crucial to consult the specific service manual for your model year. Even small variations can impact safety.

Bolt Grade and Material

It's not enough to simply know the bolt size; you also need to use the correct grade of bolt. Caliper bracket bolts are typically high-strength bolts, usually grade 10.9 or higher for metric bolts. The grade is usually stamped on the bolt head. Using a lower-grade bolt can lead to premature failure.

Also, make sure you are using the correct material. Most caliper bracket bolts are made of steel, but some may have a special coating to prevent corrosion. It is best to use the same type of bolt that originally came with the vehicle.

Torque Specifications

Once you have the correct bolts, it's essential to torque them to the manufacturer's specifications. Over-torquing can stretch or break the bolts, while under-torquing can lead to loosening and vibration. Torque specifications are typically found in the vehicle's repair manual. Using a torque wrench is crucial to ensure accurate tightening.

As a general guideline, M12 bolts in this application often require a torque between 60-80 ft-lbs (80-108 Nm), but never rely on this general number. Consult your vehicle's specific repair manual for the exact torque value.

Helpful Tips and Considerations

Always Replace in Pairs: When replacing caliper bracket bolts, it's best to replace them in pairs. This ensures that both bolts have the same strength and clamping force.

Use New Bolts: Caliper bracket bolts are often torque-to-yield (TTY) bolts, which are designed to stretch slightly when tightened. These bolts should always be replaced with new ones, as they may not provide the same clamping force if reused.

Clean the Threads: Before installing the new bolts, clean the threads in the steering knuckle or caliper bracket. This will help ensure proper tightening and prevent corrosion. A thread chaser can be very helpful for this.

Apply Threadlocker: Applying a small amount of threadlocker (e.g., Loctite) to the bolt threads can help prevent loosening due to vibration. Use a medium-strength threadlocker (blue).

Inspect the Caliper Bracket: While you're working on the brakes, take the time to inspect the caliper bracket for any signs of damage, such as cracks or corrosion. If the bracket is damaged, it should be replaced.

Consult a Professional: If you are not comfortable performing this repair yourself, it's best to consult a qualified mechanic. Brakes are a critical safety system, and it's important to ensure that they are properly maintained.

Finding the Right Bolt

Several sources can help you find the correct caliper bracket bolt size for your Nissan Altima:

Vehicle Repair Manual: This is the best source of information, as it provides the exact specifications for your specific vehicle.

Parts Catalogs: Online parts catalogs, such as those offered by auto parts stores and online retailers, can often provide bolt sizes. Enter your vehicle's year, make, and model to find the correct parts.

Dealership: Your local Nissan dealership can also provide the correct bolt size and part number.

Online Forums: Nissan Altima forums can be a helpful resource for information. Other owners may have encountered the same issue and can provide guidance. However, always verify the information you find online with a reliable source.

By carefully following these guidelines, you can ensure that you use the correct caliper bracket bolt size and torque specifications for your Nissan Altima, contributing to safe and effective braking performance.