Radian 3QXT › fit in › Toyota 4Runner

Will the Diono Radian 3QXT fit in a 2010–2024 Toyota 4Runner?

Yes — the Diono Radian 3QXT fits a 2010–2024 Toyota 4Runner, with a caveat.
The Radian 3QXT is about 17" wide; the 4Runner's usable rear bench is about 52". It fits one rear position comfortably. Three even fit across the back (51" needed vs 52"). Note: rear legroom here is limited, so a rear-facing install may crowd the front passenger.

17"Radian 3QXT width

52"4Runner rear bench

Yesthree across

★★★☆☆NHTSA Ease-of-Use

Check the Radian 3QXT on Amazon → All seats for a 4Runner

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What fits this 4Runner

One seat, rear position: Yes. The Radian 3QXT installs in an outboard rear position of a 2010–2024 Toyota 4Runner, though you may slide the front seat forward for rear-facing.
Three across: Yes — three need ~51" against a ~52" bench. Test-fit; three-across is decided by half-inches.
Modes this seat covers: rear-facing → forward-facing → booster.
LATCH: lower anchors up to 40 lb; the 4Runner has 2 lower-anchor positions.

ℹ️ Informational only — built from NHTSA public car-seat ratings and published seat/vehicle dimensions. This is not a safety certification and not a substitute for the seat and vehicle manuals. Always confirm the fit and install yourself before every trip. The Radian 3QXT's width (Diono published spec (17 in)) and the 4Runner's rear-bench width (Toyota dimensions + owner measurements (approx); body-on-frame, upright rear bench) are both approximate — confirm with a test-fit before buying.

Common questions

Will the Diono Radian 3QXT fit in a 2010–2024 Toyota 4Runner?

Yes — the Diono Radian 3QXT (17" wide) fits a single rear seating position in a 2010–2024 Toyota 4Runner. Because this vehicle has limited rear legroom, a rear-facing install may require sliding the front seat forward. Three of them also fit across its roughly 52" rear bench.

Can you fit three Radian 3QXTs across a 4Runner?

Yes — three Radian 3QXTs need about 51" and the 4Runner's usable bench is about 52". It's close, so test-fit before buying.

Sources: seat ratings & modes — NHTSA (pulled 2026-06-18); dimensions — manufacturer specs and owner measurements. Informational only — built from NHTSA public car-seat ratings and published seat/vehicle dimensions. This is not a safety certification and not a substitute for the seat and vehicle manuals. Always confirm the fit and install yourself before every trip.