Radian 3QXT › fit in › Subaru Ascent
Will the Diono Radian 3QXT fit in a 2019–2024 Subaru Ascent?
Yes — the Diono Radian 3QXT fits a 2019–2024 Subaru Ascent.
The Radian 3QXT is about 17" wide; the Ascent's usable rear bench is about 53". It fits one rear position comfortably. Three even fit across the back (51" needed vs 53").
The Radian 3QXT is about 17" wide; the Ascent's usable rear bench is about 53". It fits one rear position comfortably. Three even fit across the back (51" needed vs 53").
17"Radian 3QXT width
53"Ascent rear bench
Yesthree across
★★★☆☆NHTSA Ease-of-Use
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What fits this Ascent
- One seat, rear position: Yes. The Radian 3QXT installs in an outboard rear position of a 2019–2024 Subaru Ascent with room to spare.
- Three across: Yes — three need ~51" against a ~53" 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 Ascent 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 Ascent's rear-bench width (Typical for 3-row suv — approximate, verify install in your vehicle) are both approximate — confirm with a test-fit before buying.
Common questions
Will the Diono Radian 3QXT fit in a 2019–2024 Subaru Ascent?
Yes — the Diono Radian 3QXT (17" wide) fits a single rear seating position in a 2019–2024 Subaru Ascent. Three of them also fit across its roughly 53" rear bench.
Can you fit three Radian 3QXTs across a Ascent?
Yes — three Radian 3QXTs need about 51" and the Ascent's usable bench is about 53". 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.