Having between the three of us owned at least six Radians over the years we were thrilled to get our hands on Diono’s new line-up of seats, the Rainier, Pacifica, and Olympia, the beefier cousins to the Radian series of seats. Here we will review the Rainier and Olympia specifically, the bookends of Diono’s new seats.
Olympia ~$299
Rear-facing: 5-45lbs, or 44″ tall, or head within 1.5″ of top of shell
Forward-facing: 22-65lbs, or 57″ tall
Booster: 50-110lbs
Expiry: 8 years in harness mode, 12 years in booster mode
Two colours: Graphite, Shadow (shown)
Pacifica ~$339 (not reviewed in this post)
Rear-facing: 5-50lbs, or 44″ tall, or head within 1.5″ of top of shell
Forward-facing: 22-65lbs, or 57″ tall
Booster: 50-120lbs
Expiry: 8 years in harness mode, 12 years in booster mode
Three colours: Graphite, Shadow, Sunburst (shown)
Rainier ~$379
Rear-facing: 5-50lbs, or 44″ tall, or head within 1.5″ of top of shell
Forward-facing: 22-65lbs, or 57″ tall
Booster: 50-120lbs
Expiry: 8 years in harness mode, 12 years in booster mode
Internal head-wings with 12 adjustment positions, infant insert included
Five colours: Houndstooth, Graphite, Glacier (shown), Orchid, Shadow
Being extremely familiar with Radians we were keen to compare the seats for size, features, and fit. Folded they are the same height (grey is the Rainier, Purple is a Radian RXT). The Rainier (say it out loud, pronounced RAIN-eer) appears much larger than the Radian (not a shrinking violet by any means!), but other than extra width at the top, it’s the same height. The extra depth offers potential side impact protection, a feature we are likely to see on more and more seats as side impact requirements are phased in on US seats.
An optical illusion? Looks taller, but isn’t. What that means for you? Height wise, if your child fits a Radian then they’ll also fit the Rainier (and Olympia, and Pacifica), and the same goes for your vehicle (more on width later). Grab a friend’s seat to give it a go before committing to purchasing.
The Rainier and Olympia are very cushy, coming with a squishy and comfortable 1″ of memory foam in the bum area, compared to the lesser amount in the Radian. Jen has driven cross-country more than once in Radians and her kids have never complained (not about that anyway…), but who says no to extra padding for the derriere? This could potentially mean that the Rainier is outgrown a hair earlier than the Radian as you lose a tiny bit of internal seated height, but it will really be minimal as the foam compresses.
The required rear-facing boot is, to our eyes, identical, which again means that if a Radian installs in a vehicle then a Rainier/Pacifica/Olympia will too (have we mentioned the importance of trying before you buy?). As Jen has several, she chose to label them, so when the time comes she can retire an expired boot with the seat it came with.
Deluxe infant padding – shown in grey. Comes standard on the Rainier, regular infant padding comes with the Pacifica, not available on the Olympia. Same proportions as the Radian RXT’s padding (shown in brown), but the grey ‘deluxe’ padding is definitely squishier. Whether you choose to use it with your baby or not is up to you, as it’s there for comfort and is optional. It may improve fit with a small baby (see fit pictures below).
The Rainier comes out of the box set up for a larger forward-facing child – adding an unnecessary and potentially misuse-inducing element to parents who largely purchase this seat for its impressive rear-facing capabilities. If it were up to us it would come with the harness on the lowest setting, and the crotch buckle on the innermost position. READ YOUR MANUAL when you pull it out of the box to ensure the seat is set up properly for your child.
This new fabric, however, is a hit with Jen’s kids. It’s called “Smooth Sport Silk Fabric with Sport Tek trim” and it IS quite soft. It has a look sort of like neoprene but isn’t that texture at all. We were worried it might catch or get pilly, but so far that’s not at all the case. Jen’s texture-particular 6 year old described it as ‘rhinoceros skin’ which she insisted was a good thing, and the usually sweaty 4 year old has been markedly cooler in this one versus the Ultra Suede of the purple RXT pictured earlier. Time will tell if it holds up as well as the purple RXT has.



How about fit to vehicle from a front-to-back perspective? Like the Radians, it is a large (and heavy!) seat when rear-facing, weighing in at approximately 26lbs. No noodles or rolled towels are permitted to make the seat more reclined, so if you’re intending it for use with a newborn or young baby make sure the seat installs sufficiently reclined for your needs — it is absolutely critical that you protect the airway of a newborn and eliminate the potential for head flop. Vehicles with very flat seats will naturally enable Diono seats to install very reclined — but take up a ton of room while doing so. Vehicles with very sloped seats will naturally enable Diono seats to install quite upright – super for older kids, not so much for newbies. Once a child has complete head control and can sit up unassisted you may use an Angle Adjuster (foam block) to sit the seat more upright, leaving more leg room in the row in front of it.
Sometimes the Angle Adjuster can mean the difference between being incompatible due to size, and a perfect fit. Here we try it in a small car (2003 Honda Civic) and compare leg room for the front seat occupants.
Above, from left to right: behind the driver with angle adjuster: a moderately tall person can easily drive; centre with angle adjuster (and a seat belt install because you can’t ‘borrow’ lower anchors in most vehicles) allows enough room to put the driver’s seat ALL the way back!; behind the driver with no angle adjuster: no human could safely drive like that.


Fit to child was marvelous, as we expected!
This tester turned 4 while trying the seat out, weighing in at 39lbs, and about 41″ tall. She has quite a bit of time remaining in this seat by height and weight, and was pleased to ride rear-facing to share her impressions. Low sides to enable easy climbing in, lots of leg room, comfortable fabric (although she does wish it were pink…but that’s the case for everything these days) — she gives it two thumbs up.
Teeny tiny! At about 8lbs this wee one fit beautifully with the included infant padding. The lowest harness position was approximately 1″ below her shoulders, meaning she could have been that much shorter in the torso and still fit.
4 months old and about 15lbs. Another nice fit!
Getting bigger and fitting well. Again the big foam comfort pads are optional rear-facing. They will be too large on a small baby as there just won’t be enough torso room to place them, but if they fit go ahead and use them!
Forward-facing the Rainier/Pacifica/Olympia provides long-lasting harnessing opportunities. Kids close to outgrowing it (6.5, 45lbs, 46″ tall shown on left/ 6, 52lbs, 48″ tall shown on right) might find the head wings confining, and if that’s the case the head-wing-less Pacifica or Olympia might be a better option (shown centre: 4 years old, 39lb, 41″ tall). Memory foam harness pads are required in this mode. You get used to them, although they are very stiff in winter.
The Rainier/Pacifica/Olympia is least impressive in its booster function. Belt fit varies greatly in any booster, depending entirely on the belt geometry of the vehicle and the shape and size of the child. The Diono seats can not be used in booster mode until the child weighs 50lbs — at which point many kids will be too tall to fit properly. In our tests the lap belt fit was good (yay!) but the shoulder belt fit was hit or miss — and not adjustable any higher on the Rainier (left, in blue dress), or at all on the Olympia (right, with sunglasses). In addition the shoulder belt guide on the Olympia holds the belt so far out from this child’s chest that it would really take a much heftier child to fill it out sufficiently. It’s important that the shoulder belt makes contact with the chest for proper belt fit while in a booster or adult seat belt alone. This leggy child complained that the seat pan was too short to comfortably support her legs. As a booster it may fit your child for a short period of time, but we recommend you don’t count on it. These seats are excellent options for long-lasting rear-facing and forward-facing, and shop with that in mind, leaving the booster decision for when the time comes.
Final observations:
Diono has made some nice changes to the much-loved Radian line, although in really tight squeezes a Radian might be a better option. Cushy fabrics in fun colours (Jen loves orange…why can’t her kids?), super comfort features like plush memory foam in the seat pan, and exceptionally high rear-facing specs make the Rainier/Pacifica/Olympia a definite contender for those wanting to rear-face well past the minimums as is currently recommended by everyone. MOST kids will reach the height limit before the weight limit, so the added poundage seen on these new seats, while impressive, may not be needed in most cases. The top harness height is sufficient to keep all but the tallest or long-torsoed kids safely harnessed until they are booster-ready, and low sides make it easy to load a child in and out. Offering similar specs on a range of seats allows parents and caregivers to choose the features they need and want (head wings, infant padding, etc), and pay accordingly.
These seats are heavy – if you are moving them frequently between vehicles that may be a deterrent. The harness adjuster (the pull tail to tighten the harness) is a ratcheting tug-tug-tug motion, and takes some getting used to if you’re familiar with one long smooth pull instead. Getting the last bit of slack out so the harness passes the pinch test can be challenging, but if you get in the habit of not loosening and tightening the harness every time it’s not a deal breaker at all. Booster mode may not work well, or for very long, with your child, and if it does – great. But if you are shopping for this seat for your young baby remember that boostering is years away, and cross that bridge when you come to it.
Diono generously provided the seats used in this review – but our opinions are our own. Thanks to them we are able to share the love! One Olympia in Graphite will be given away each locally on Vancouver Island, BC and the Barrie, ON area (or further away if you are the lucky winner and wish to pay for shipping). Woohoo! See the Rafflecopter below to enter, and thanks for reading!