Measuring Thrust Angle and Rear Axle Square Alignment 2015 Jeep Wrangler JK / JKU

January 22, 2018

Learn how to measure thrust angle and rear axle alignment for your 2015 Jeep Wrangler JK, ensuring optimal performance on and off the road.

Quick Look

Category

Mods, Maintenance, Off-Road

Brand

Jeep

Product

Wrangler JK

Use Case

Rear axle alignment measurement

Overview

Aligning your Jeep's rear axle is crucial for both on-road handling and off-road performance. If your rear axle is out of alignment, it can cause uneven tire wear, reduced fuel efficiency, and in severe cases, instability on challenging terrains. In this article, we will go through the process of measuring and correcting the thrust angle and rear axle alignment for a 2015 Jeep Wrangler JK (JKU).

What This Covers

This guide will cover:

• Understanding thrust angle
• Tools needed for measuring alignment
• Step-by-step measurement process
• How to make necessary adjustments

Step-by-Step Breakdown

Let's dive into the steps required to check your Jeep's rear axle alignment accurately.

1. Gathering Tools: All you need for this task is a reliable tape measure and some basic hand tools. Ensure your Jeep is parked on a level surface to get accurate measurements.
2. Choosing Reference Points: Select a consistent reference point for your measurements. A commonly used spot is the front body mount bolt, but other factory mounting locations may work as well. Establish where this point is on both sides of the vehicle to minimize measurement discrepancies.
3. Measuring the Axle Position: With your tape measure, measure from the reference point back to the outer edge of the rear tires. Ensure that both sides are measured to establish symmetry. Commonly, you’ll find that one side may have a half-inch discrepancy indicating misalignment.
4. Calculating Thrust Angle: The thrust angle can be calculated using the measurements you've taken. Input the distance between the two measuring points on the tires and the half-inch difference into the right formula. This will yield a rough degrees measurement that should ideally match professionally obtained alignment data.
5. Making Adjustments: If you’ve determined your rear axle is off, adjustments can be made to the lower and upper control arms on the passenger side to bring the axle back into alignment. Make small adjustments, re-measuring frequently until the desired alignment is achieved.

Helpful Tips

Here are a few tips to consider during the alignment process:

• Be patient and precise with your measurements to avoid unnecessary adjustments.
• Regularly check your measurements as you adjust to avoid overcorrecting.
• Consider installing adjustable control arms if you're frequently making adjustments, as they allow for more fine-tuning.
• After making adjustments, it’s a great idea to get a professional alignment check for peace of mind.

Key Takeaways

Correct axle alignment on your Jeep is vital, particularly when you’ve made modifications such as larger tires. By following the steps outlined here, you can confirm the alignment issues and make necessary adjustments to ensure optimal performance. Remember, keeping your Jeep in alignment not only enhances its drivability but also prolongs the life of your tires and suspension components, enhancing your off-road adventures.