When your Lippert electric slide-out starts binding, slipping, or refusing to retract cleanly, the internal round core is often the culprit. This OEM-specification Lippert part number 379400 gives you a direct, like-for-like replacement so you can restore smooth, reliable slide-out operation without replacing the entire mechanism. At under half a pound and a compact 5" x 3" x 0.5" profile, it ships quickly and installs with basic hand tools.
Lippert Components is the dominant supplier of slide-out systems in the North American RV industry, found in rigs from Forest River, Keystone, Coachmen, Jayco, Grand Design, and dozens of other brands. Their electric slide-out mechanisms rely on a precisely machined internal core to transfer motor torque into smooth, controlled in-and-out travel. Over time -- especially after seasons of vibration, road grit, and weathering -- that core can wear, crack, or develop play that shows up as grinding noise, uneven extension, or a slide that wont seat flush.
Part number 379400 is the 3/4" diameter round-profile core used in select Lippert slide-out rail and rack assemblies. Replacing just this component, rather than the full slide motor or gearbox assembly, is the most cost-effective fix for core-related slide failures.
Manufactured to the same dimensional and material spec as the original, so it installs without modification or adapter hardware.
At 0.35 lbs and 5" x 3" x 0.5", this core ships easily and tucks into tight slide-out mechanism bays without clearance issues.
The 3/4" diameter round cross-section is critical -- do not substitute a square or flat core. Verify your existing core diameter before ordering.
Lippert slide systems are found across dozens of RV brands. If your trailer or fifth wheel uses a Lippert electric slide, this core is likely the right match.
Lippert produces slide-out cores in both round and square profiles, and in multiple diameters. The 379400 is specifically the 3/4" diameter round variant. Before ordering, remove your existing core (or photograph it next to a tape measure) and confirm:
If your slide uses a 1" round core or any square-profile core, you will need a different Lippert part number. Lippert also offers complete rack-and-pinion slide kits if additional components show wear.
Lippert slide-out mechanisms using 3/4" round cores are commonly found in:
Cross-reference your existing core against Lippert part 379400 using your RV's VIN-based parts lookup or the Lippert service line if you are unsure of your slide generation.