2018 Dodge Ram Body Suspension Parts Diagram: A Complete Guide

Understanding the suspension system on your 2018 Dodge Ram is key to maintaining ride quality, handling, and safety. This guide breaks down the body suspension parts diagram, explaining each component’s purpose and location. Whether you own a Ram 1500, 2500, or 3500, the general layout is similar, though heavy-duty models use stouter parts.

Overview of the 2018 Dodge Ram Suspension System

The 2018 Dodge Ram uses a front independent suspension with coil springs on all models, while the rear setup varies. Light-duty Rams (1500) have a five-link coil spring rear suspension, providing a smooth ride and good articulation. Heavy-duty Rams (2500/3500) use a solid rear axle with leaf springs for greater load capacity. All models include a sway bar front and rear to reduce body roll. The system is designed to absorb bumps, maintain tire contact with the road, and support vehicle weight.

Front Suspension Components

Control Arms

The front suspension uses upper and lower control arms (A-arms) that connect the wheel hub to the frame. They pivot on bushings, allowing vertical wheel movement while controlling side-to-side motion. On 2018 Rams, the lower control arm is a larger stamped steel piece; the upper is smaller. Ball joints at the outer ends connect to the steering knuckle.

Sway Bar

The front sway bar (stabilizer bar) is a torsion spring that links the left and right control arms. It reduces body lean during cornering. The bar is mounted to the frame with bushings, and end links connect it to the control arms. Worn bushings or end links can cause clunking noises.

Shocks and Struts

2018 Rams use front shock absorbers separate from the spring (not a strut design). The shock is mounted inside the coil spring. It dampens spring oscillations. Over time, shocks lose their damping ability, leading to a bouncy ride and longer stopping distances.

Coil Springs

Coil springs support the vehicle’s weight and absorb road impacts. They are located between the lower control arm and a spring seat on the frame. Spring rate varies by engine and trim (e.g., Heavy-Duty or Off-Road packages). Sagging springs can reduce ride height and alter alignment.

Steering Components

Tie rods connect the steering rack to the steering knuckle. The inner tie rod attaches to the rack, the outer to the knuckle. Ball joints at these connections wear over time, causing play. Regular inspection prevents steering wander.

Rear Suspension Components

Leaf Springs or Coil Springs

Ram 1500 models have a five-link coil spring setup: two lower trailing arms, two upper trailing arms, and a track bar. The coils provide ride comfort while the links control axle motion. Ram 2500/3500 models use multi-leaf springs (typically 3-4 leaves) mounted longitudinally under the axle. Leaf springs support heavy loads and are simpler but stiffer.

Shock Absorbers

Rear shocks are mounted vertically between the frame and axle or suspension link. They control spring rebound and compression. Some heavy-duty Rams also have auxiliary shocks for improved damping when towing.

Sway Bar

The rear sway bar is often smaller than the front. It links the axle to the frame via end links. On Ram 1500 coil-sprung axles, the bar helps control articulation. On leaf-spring trucks, the bar is sometimes omitted on base trims.

Track Bar

On Ram 1500 rear coil suspension, a track bar (Panhard bar) is used. It connects the axle to the frame laterally, preventing side-to-side movement. This is critical for maintaining axle centering during turns. Bushings here are wear items.

Control Arms

For Ram 1500, the five-link system includes two upper and two lower control arms (trailing arms). They locate the axle fore-aft and control pinion angle. Bushings in these arms degrade over time, causing axle shift and driveline vibration.

Suspension Parts Diagram Explained

A typical suspension parts diagram for the 2018 Ram shows an exploded view of each assembly. Front suspension diagrams include the coil spring, shock absorber, upper/lower control arms, ball joints, sway bar and links, and steering knuckle. Rear diagrams for 1500 show the coil springs, shocks, upper/lower control arms, track bar, and sway bar; for 2500/3500, leaf springs, shocks, U-bolts, and spring hangers. Numbers or callouts identify each part. You can find factory diagrams in the service manual or on parts websites like Mopar’s official catalog. When using a diagram, note that parts are often sold as assemblies (e.g., control arm with ball joint) or individually.

Common Wear Items and Maintenance

• Ball Joints: Front upper and lower ball joints wear over time, causing looseness and tire wear. Check for play during front-end inspection.
• Shocks and Struts: Replace around 50,000-70,000 miles or sooner if you notice excessive bounce or fluid leaks.
• Sway Bar Bushings and End Links: Deteriorate with age; replace if you hear clunks over bumps.
• Control Arm Bushings: Cracking or sagging leads to alignment drift and noise.
• Springs: Leaf springs can sag, coil springs can break; inspect for cracks or settling.
• Tie Rod Ends: Worn ends cause steering play; replace in pairs.

Regularly inspect your suspension for leaks, cracks, or loose components. Listen for knocking or squeaking when driving over rough roads. Keeping the suspension in good shape improves fuel economy, tire life, and safety.

Upgrading vs. Replacing: What You Should Know

If you use your Ram for heavy towing or off-roading, you may consider upgrades. For towing, heavier-duty shocks (e.g., Bilstein 5100s) and helper springs (like Timbren) can reduce squat. For off-road, lifted springs and longer shocks increase clearance. However, changing ride height affects alignment angles—expect to adjust camber and caster. Stick with proven brands: Moog, AC Delco, Monroe, Bilstein, and Mopar. Avoid low-quality parts that compromise safety. For daily driving, OEM replacements are perfectly adequate. Always replace components in pairs (both front shocks, both upper ball joints, etc.) to maintain balance.

Final Recommendation

For a 2018 Dodge Ram owner, the best approach is to start with a factory service manual that includes detailed suspension diagrams and torque specs. If you’re doing your own work, invest in quality tools like a ball joint press and impact wrench. For parts, choose OEM or reputable aftermarket brands that match the original design. After any suspension repair or upgrade, get a professional alignment to ensure proper handling and tire wear. Regular inspections, especially before towing season or long trips, will keep your Ram riding smoothly for years to come.