Upgrading Losi LST Suspension and Steering Parts: A Practical Guide

The Losi LST series—including the original LST, LST2, and XXL—are legendary monster trucks known for their massive size and brute force. But like any hobby-grade RC, the suspension and steering system can wear out or benefit from upgrades. Whether you’re replacing broken parts after a hard bash or building a custom racer, choosing the right Losi LST suspension and steering parts makes a big difference in handling, durability, and overall fun.

This guide covers the key components: shock absorbers, A-arms, steering knuckles, turnbuckles, servo savers, and bulkheads. You’ll learn what to look for, how to spot compatible upgrades, and practical tips for installation and tuning.

Losi LST Suspension Parts

Shock Absorbers (Dampers)

The stock shocks on the LST are decent for general bashing, but they often leak over time or lack the damping adjustability needed for aggressive driving. When shopping for replacement or upgrade shocks, consider:

• Bore size and oil volume: Larger bore shocks (like 16mm or 23mm) handle heat better and provide more consistent damping.
• Adjustability: Look for threaded bodies or preload rings so you can fine-tune ride height and spring tension.
• Rebound and compression damping: Some aftermarket shocks offer separate adjustments, letting you dial in the truck’s behavior for different surfaces—loose dirt, hardpack, or grass.
• Build quality: CNC aluminum bodies resist bending and leaks much better than plastic or cheap pot metal.

Popular upgrade shocks for the LST include the Losi 23mm Big Bore Shocks (LAW) or Pro-Line PowerStroke Edge shocks. They bolt in with minor modifications and dramatically improve performance.

Installing new shocks

• Remove the old shocks and clean the shock towers.
• Fill new shocks with silicone oil (usually 30–50 weight for general bashing, lighter for smoother terrain).
• Bleed air bubbles by slowly compressing the shaft.
• Set spring preload so the truck sits level with about 30% sag when placed on the ground.

A-Arms (Suspension Arms)

The stock plastic A-arms on the LST are strong but can crack under hard landings or wheelies. Aftermarket options are typically made from:

• Reinforced nylon: Stiffer yet forgiving, great for bashing.
• Aluminum: Strongest but heavier; can transfer stress to other parts like the bulkhead.
• Carbon fiber or fiberglass: Light and stiff, but brittle in cold weather.

Compatibility notes

• LST and LST2 A-arms are generally interchangeable, but the XXL uses slightly different dimensions—verify before buying.
• Some aftermarket arms come with pivot ball bearings or hardened hinge pins. That reduces slop and improves steering precision.
• RPM A-arms are a popular upgrade: flexible enough to absorb impacts yet durable.

When installing, inspect the bulkhead pivot pins and bushings. Replace them if worn to eliminate slop.

Suspension Sway Bars

Sway bars reduce body roll in turns. The stock LST might not have one, or it may be a thin wire that bends easily. Adding a thicker aftermarket sway bar (like the one from Losi or Hot Racing) improves cornering stability without sacrificing articulation.

• Front sway bar: Helps with steering response.
• Rear sway bar: Keeps the back end planted when accelerating out of corners.
• Swain bar links and mounts should be aluminum to avoid flex.

Losi LST Steering Parts

Steering Knuckles and C-Hubs

These parts take a beating, especially on a heavy truck like the LST. Stock plastic knuckles can strip or break. Upgrade to:

• Hardened steel or titanium axle stubs for the bearing surfaces.
• Aluminum steering knuckles with replaceable inserts for toe and camber adjustments.
• CRC or Integy brand knuckles are common, but check for proper bearing fit: some aftermarket knuckles use different bearing sizes.

Pro tip: Use shims if the steering links are too tight or too loose after installing new knuckles.

Turnbuckles and Tie Rods

Adjustable turnbuckles let you set toe and camber precisely. Stock turnbuckles are often plastic, which can bend or strip threads. Consider:

• Steel or titanium turnbuckles: Stronger, but can be heavy. Titanium is lighter and stronger but costs more.
• Rod ends: Build your own if you want custom length. Use stainless steel rod ends with silicone boots to keep dirt out.
• Thread locking: Apply blue Loctite to the threads so they don’t back out during runs.

Servo Saver and Steering Bellcranks

A servo saver protects the servo from shock loads. The stock saver can be weak, causing sloppy steering. Upgrade options:

• Adjustable servo saver (like the Hitec or Losi aluminum one) lets you set the tension.
• Direct servo link (no saver) for racing if you accept the risk of servo damage.
• Bellcrank assembly: CNC aluminum bellcranks with sealed bearings reduce play and improve feedback. Xtra Speed or GPM make direct-fit versions.

Steering Servo

While not exactly a “suspension steering part,” the servo is crucial. A high-torque servo (400+ oz-in) is recommended for the LST. Use metal gears and a metal servo arm for reliability.

Steering System Maintenance

• Check all link balls and rod ends for wear. Replace any that are loose.
• Lubricate the steering pivot points with silicone grease.
• Tighten the servo horn screw regularly; it tends to loosen.

Final Recommendation

For most Losi LST owners who bash or race, focus on upgrading the shock absorbers and the steering components first. Start with a set of quality big bore shocks (Losi 23mm or Pro-Line) and replace the A-arms with RPM units if they crack. For steering, a metal servo saver and upgraded turnbuckles give you precise control. If budget allows, add aluminum knuckles and a sway bar set.

Avoid mixing unknown brands that may require excessive modification. Stick with proven brands like Losi, Pro-Line, RPM, and Hot Racing. Measure twice before ordering: many parts are model-specific. With the right upgrades, your Losi LST will handle like a new truck and survive harder bash sessions.