# FRONT RUNNER Front Runner LC250/GX5503/4 Slimline3 mounting system

Canonical page: https://configmyrig.com/products/front-runner-lc250-gx5503-4-slimline3-mounting-system

Front Runner LC250/GX5503/4 Slimline3 mounting system

## Selected configuration

- Part/component: MSTL002
- Configuration: Mounting rails only / no rack tray
- Listed parts: $379.00 USD / selected configuration
- Source checked: October 30, 2026 (America/New_York)
- Fitment: Manufacturer explicitly names LC250 Prado / GX550 mounting system; exact US model year/grade/roof/VIN must be confirmed. Maker says permits sunroof operation; this is not approval for every panoramic roof.
- Product mass: 17.6 lb product mass
- Net vehicle addition: Net addition unverified
- Weight basis: Maker product assembly mass8kg/17.6lb, not installed net vehicle change; OEM rails removed, separate tray and any extra gear unaccounted.
- Professional install: 1.5–3 hr; researched planning estimate
- Basis: 1.5–3hr task-based professional planning estimate for OEM rail removal, seals and mounting-rail alignment/fastening based on MSTL002 guide; tray assembly and extra accessories require separate quote. Numeric published labor not found.
- Contents: Left/right3/4 mounting rails, integrated fairing, stainless hardware and fitting instructions; Slimline3 rack tray is separate.
- Critical specifications: Pair of3CR12 stainless rails with integrated fairing;1459×80×120mm per side rail. Maker assembly weight8kg/17.6lb. Listed top of complete Slimline3 rack80mm above roof crown.
- Supporting work: OEM roof rails must be removed; no drilling per maker. This is an incomplete rack mounting component, not a roof-cargo platform by itself. Confirm roof seals, tray sizing, vehicle roof limits and full installation quote.

## Prerequisites

- Selected product / listed contents (included): Left/right3/4 mounting rails, integrated fairing, stainless hardware and fitting instructions; Slimline3 rack tray is separate.
- Matched Slimline3 tray / complete rack design (check): Obtain the specifically compatible3/4 Slimline3 tray and full bill of materials. Other-brand/SlimlineII/Slimsport racks are not approved matches.
- Complete installation and exact vehicle quote (quote): Confirm the current packing list, exact vehicle and any unpriced support parts or labor with the supplier/installer.
- Installation / compatibility notes (check): OEM roof rails must be removed; no drilling per maker. This is an incomplete rack mounting component, not a roof-cargo platform by itself. Confirm roof seals, tray sizing, vehicle roof limits and full installation quote.
- Installed net weight (check): Product weight or factory equipment removed is not fully verified. Do not use shipping weight or assume zero additional load.

## Seller offers (selected configuration, low to high)

- [FRONT RUNNER](https://www.dometic.com/en-us/product/toyota-land-cruiser-250-prado-lexus-gx550-3-4-mounting-system-mstl002): $379.00 USD

Prices are dated snapshots; tax, shipping, installation and unlisted supporting equipment are extra. Availability is not inferred.

## Installation resources

- [Front Runner MSTL0023/4 mounting instructions](https://instructions.dometic.com/collateral/doc/F_MSTL002.pdf): official; Exact MSTL002 LC250/GX550 mounting component guide.. Manufacturer resource; current instructions and exact selected SKU must still be confirmed. Full video playback is not independently verified.

## All documented options

- [Mounting rails only / no rack tray](https://configmyrig.com/products/front-runner-lc250-gx5503-4-slimline3-mounting-system): MSTL002; $379.00 USD / selected configuration; 17.6 lb product mass

## Owner evidence

No sufficiently matched report added. No review rating is inferred.

## Related guidance

- [Planning guide](https://configmyrig.com/guides/roof-loads-and-camping)
- [FRONT RUNNER](https://configmyrig.com/brands/front-runner)
- [Roof & camping](https://configmyrig.com/categories/roof-and-camping)

AI-assisted planning; exact vehicle/application and current supplier documentation require confirmation.