2017 Diono Radian RXT Review: The Folding Carseat that’s Great for 3-Across and Extended Rear-Facing
See our review of the updated 2019 Diono 3RXT here
Updated 11-08-18
Recall notice: most Diono convertibles, including the Radian RXT, were recalled in October 2017. See recall details here. 2018 Diono Radian RXT models currently for sale have revised (lower) weight limits and other modifications so this review only applies to RXT models manufactured before the October recall. Updated review is coming soon.
The Diono Radian RXT fills a niche for parents and caregivers looking for a narrow carseat that can hold a big kid. The Radian line of seats is known for being 3-across friendly—when you have a tiny back seat, these are the carseats you generally look at first. The Radian R-series, the R100, R120, and Radian RXT, all have basically the same shell design but features distinguish them from each other. Diono discontinued the R100 and R120 in September 2018 and refreshed the carseats in the form of the 3 R and 3RX. This review will focus on the previous version of the RXT, but the information is similar for all the Radians and we have a review of the new 3 RXT forthcoming.
| Radian Model |
RF Weight Limits
|
FF Weight Limits
|
Booster Weight Limits
|
Features
|
| R100
*Discontinued |
5-40 lbs.
|
20-65 lbs.
|
50-100 lbs.
|
|
| R120
*Discontinued |
5-45 lbs.
|
20-65 lbs.
|
50-120 lbs.
|
|
| RXT
|
5-45 lbs.
|
20-65 lbs.
|
50-120 lbs.
|
|
Radian RXT Weight and Height Limits
- 5-45 lbs. rear-facing with at least 1.5” of carseat above the child’s head or total height of 44”
- 20-65* lbs. forward-facing with a child less than 57” tall
- 50-120 lbs. as a booster with a child 40-57” tall, and child’s shoulders must also be at or above the 4th set of harness slots
*models manufactured prior to 9/5/17 have a forward-facing weight limit of 20-80 lbs.
Radian RXT Overview
- One of the narrowest convertibles on the market: makes a 3-across much easier!
- SuperLATCH deluxe push-on connectors
- 3 crotch/buckle strap positions
- Safe Stop Load Limiter
- Full steel reinforced frame and aluminum reinforced sides
- Folds flat for travel and storage
- Lined with EPS foam
- 12-position adjustable headrest
- 5 harness slot positions
- Rear-facing tether capability
- Low profile makes loading and unloading child easier
Radian RXT Measurements:
Harness height: 9”, 10.5”, 12”, 15”, 17.5”
Crotch strap depth: 3.5”, 5.5”, 7”
External widest point: approx. 17” at widest point at shoulders, 16.5” at widest point at thighs
Internal widest point: approx. 14” at widest point at shoulders, 14.5” at widest point at thighs
Seat weight: 26.5 lbs.
Installation
Rear-Facing Installation
Installation of the Radian is either easy or hard; there doesn’t seem to be a middle ground with this carseat. In order to install the Radian rear-facing, you must first attach the rear-facing base/boot. That base will set the recline for you automatically—you will not need any rolled towels or noodles to achieve a proper angle. In fact, Diono does not allow the use of rolled towels or noodles with Radians.
For an older child who has good head control and can sit upright unassisted, the Angle Adjuster accessory can be used under a rear-facing Radian to make it more upright and give front seat passengers inches more legroom too.
The RF belt path is a closed belt path, meaning it’s enclosed in plastic. If you’ve got big hands, you’ll have trouble fitting the seat belt or SuperLATCH belt through the belt path; I’ve got average-sized hands and have trouble. Because it’s closed, tightening the belt for a tight installation is difficult too. The best way to get a carseat tight is to pull the belt in the same direction as the belt path, but with a closed belt path, you can’t. You’ll eventually get it tight—it takes you longer to do so.
Forward-facing installation
Installing the Radian forward-facing is easier than RF because the cover can be pulled away for access to the FF belt path. Vehicle buckles that are on short buckle stalks or that are even with the vehicle seat may cause concern because the seat belt will bunch in the latchplate the tighter you pull. This is normal for this carseat.
Special forward-facing concerns:
Adjustable Bottom: When installing the Radian forward-facing, models manufactured after May 2016 require that the forward-facing adjustable bottom be lowered, but only if the child is over 25 lbs. Most forward-facing children will be over 25 lbs., so that means you should lower it before installing the Radian FF. Models manufactured before May 2016 have the option of using it, but it increases your chances of a successful FF install.
Safe Stop Load Limiter: This small strap that is attached to the back left of the carseat when you first receive your Radian is called a load limiter. Its purpose is to increase the amount of time over which your child feels crash forces. If you install the Radian FF for a child who weighs under 40 lbs., you must use the Safe Stop. The Safe Stop is never used rear-facing.
LATCH Installation
The SuperLATCH connectors are the deluxe push-on style connectors, but the connectors are beefier with 4 attachment “pawls” instead of the standard 1 pawl. There is an adjuster on one side of this strap. There are storage areas at the top of the shell to store the LATCH and top tether connectors when not in use. The tether strap can be used rear- or forward-facing. While tethering a forward-facing child restraint with a harness is always recommended, a top tether is not required for this seat.
vs. 
Weight Limits for SuperLATCH
| Radians manufactured before September 2009 | 48 lbs. or vehicle manufacturer’s limit, whichever is lower |
| Radians manufactured between September 2009 and March 2014 | In vehicles manufactured after 9/1/05: use SuperLATCH to carseat weight limit
In vehicles manufactured before 9/1/05: use SuperLATCH to 48 lbs. or vehicle manufacturer’s limit, whichever is lower |
| Radians manufactured beginning in March 2014 and newer | 35 lbs. rear-facing
40 lbs. forward-facing |
Once your child reaches the weight limits for SuperLATCH, switch to the vehicle seat belt for installation, whether rear- or forward-facing.
When the carseat is used as a booster, however, it may be LATCHed in at any weight. This is because the LATCH is simply holding the carseat to the vehicle while the seatbelt is restraining the child and will be the device taking crash forces.
Center LATCH installations with Non-Standard Spacing:
Diono allows LATCH installation in the center seating position if the vehicle manufacturer allows it and the LATCH anchor bars are spaced 11-14” apart.
Inflatable Seat Belts
Diono has determined that the Radian carseats can be installed with inflatable seat belts found in Ford Motor Vehicles. This does not include Mercedes vehicles or inflatable seat belts found on aircraft.
Fit to Child
The Radian RXT comes with an infant head pillow and body support. These items are optional and you can remove them at any time.
The Radian also comes with 2 sets of harness pads: a memory foam-padded set that Velcro around the chest clip and a much longer set that are rubberized on the back with metal slides on the end. The shorter harness pads MUST be used forward-facing for children under 65 lbs. (optional for rear-facing). The longer, rubberized set MUST be used forward-facing for children over 65 lbs.
Because of the well-padded cover and memory foam in the seating area, the Radian is a comfortable carseat. It won’t fit small newborns well, even with the body support, because the bottom harness slots are too high. Most kids make it easily to belt-positioning booster seat age in the harness.
The headrest provides just enough support to be comfy without getting in the way. When the Radian RXT is rear-facing and the child is using either of the bottom 2 harness slots, the headrest must be moved to the top-most position.
When used as a booster, the shoulder belt has a tendency to get caught in the shoulder belt guide. This is more pronounced in older versions of the RXT and Diono has tried to fix this problem in the latest update. It’s a serious problem when the shoulder belt gets caught in the belt guide because if a child leans forward and the shoulder belt doesn’t retract automatically, it stays loose and floppy on the child and could lead to the child being severely injured in a crash. The belt fit and geometry is otherwise very good and even earns it an IIHS Best Bet rating as a booster, but the IIHS doesn’t measure booster fit with real, moving kids.
Cover/Maintenance/Ease of Use
The cover is well-padded with a comfortable texture. Diono recommends hand washing or a front loader washing machine. Definitely hand wash the memory foam! Line dry.
The harness adjuster tightens with a tug-tug-tug motion that may take some getting used to by some caregivers. The harness height adjusts from the back of the seat. Each strap is removed from the metal splitter plate and rethreaded through the correct harness slot. Use the slots at or below the shoulders for rear-facing, above for forward-facing. Children whose shoulders are above the top harness slots, yet still weigh less than the maximum forward-facing harness weight limit, may continue to use the carseat. For those children, the tops of their ears must be below the top of the carseat.
FAA-Approval/Lifespan/Crash Guidelines
The RXT is FAA-approved for use in aircraft. It also is a heavy restraint weighing in at 26.5 lbs., so if you do travel with it, you’ll want to use a luggage cart to avoid having to carry it. The RXT does come with a padded shoulder strap for carrying and I suggest buying another to be able to carry it backpack-style if you intend to carry it. Since the Radian seats are some of the narrowest on the market, you won’t have any problems fitting one in a plane seat AND the tray table will be able to come all the way down for a forward-facer. For rear-facing, the Angle Adjuster may make the seat fit depending on the pitch of the seats on the plane your flying. Buying a snack for the person in front of the carseat certainly doesn’t hurt ;). Remember that it can only be used with the harness on the plane since belt-positioning booster seats can’t be used on planes.
Radians manufactured before May 2016 have expiration dates of 8 years as harnessed seats, 10 years as belt-positioning boosters. Radians manufactured as of May 2016 and newer have 10 year expirations from date of purchase (or DOM if you didn’t save your receipt).
Diono recommends replacement after any crash.
Advantages
- 3 Crotch Strap Positions: Having a choice of crotch strap positions makes the harness more comfortable for bigger kids.
- Low and narrow footprint means it’s more likely to fit in tight spots.
- Padded Cover: A thickly padded cover, plus the memory foam in the bum area, makes for a comfy seat.
- Folds flat for travel and storage
- Low profile makes loading and unloading child easier
- Can be installed with Ford Motor Company inflatable seat belts
Disadvantages
(In all fairness, these aren’t necessarily problems but I list them here to inform potential consumers of specific Radian RXT issues)
- Low LATCH weight limits
- Harness Adjuster: It’s tug-tug-tug can be frustrating for some used to a smooth adjuster on an infant seat.
- Installation: Often more difficult depending on the vehicle, with a higher learning curve due to the various features.
- Snug fit of the shoulder belt in booster mode is poor; shoulder belt can get caught leaving slack.
- Heavy for a carseat designed for travel
Conclusion
The Diono Radian RXT is a solid convertible seat with great rear-facing features. Its high height and weight limits accommodate big kids both rear- and forward-facing, yet it takes up less space than many of its competitors. For narrow backseats or 3-across situations, you simply can’t beat the width of the RXT. Features like rear-facing tethering, thick padding, and solid construction make the Radian RXT a solid purchase.
Thank you to Diono for supplying the RXT used in this review!
Janet, seated height is measured from bum to shoulders. Convertibles can be used from birth, assuming the child fits correctly (shoulders are above the bottom slots and baby is within the weight limits), so an older infant/toddler is good in a convertible at any point.
Another question…what’s the best way to measure seated length? With the RXT at what age/weight/length do you recommend for proper and safe use?
It depends. It’s not as narrow as the RXT, but it’s all in how the seats puzzle together. The Alpha Omega may slide underneath the Chicco or it may have to be placed behind the driver.
That’s where he currently rides on the passenger side. Can the chicco next fit accommodate three across? We sometimes have another RF car seat and a booster on the second row. We can move the booster to the third row but the other RF car seat is really cumbersome, it’s an alpha and omega something or other.
@Janet, the ProRide doesn’t have much legroom for rear-facing and it sits up pretty high on a base, so given that your ds is likely to be tall and you’re putting it into an SUV that’s relatively high up off the ground, I’d recommend against that one. Can you put him on the passenger side? Have you considered the Chicco NextFit?
Im looking for a convertible for my son. Hes only 3 months and currently in a britax b-safe infant car seat but is close to outgrowing it in length. After some research im between the Recaro Proride and the Diono Radian RXT. I drive a 2001 Chevy Tahoe so I don’t use the latch system. My husband and I both are over 6′ tall so we need as much leg room on the driver side as possible. In conclusion what car seat is recommended for a tall little guy with tall drivers? Also is it too soon to move my little guy? Hes at 27″ long and just seems to have outgrown the infant car seat. Thank you 🙂
But you know, Angel, just knowing that you can’t use LATCH in the center put you ahead of 80% of other parents, so you know more than you think you do ;).
Sorry think I got everything, should have re-read your thread , sorry :(. I just ordered 3 , if I have one in the middle the way I understand I have to seat belt it , can’t use latch and can’t share latch with the other two. Boy I thought I knew alot about car seats and turns out not so much
Hopefully this is it ! Thanks for all your help AGAIN !
Thanks Heather
OF COURSE I have to throw a curve ball and be from Canada… have to keep you on your toes 😀
thanks for the advice….I will look into your suggestions..
MY son is 15 pounds and 4 months so gotta keep on the ball he’s turning into a little porker 😀
Thanks again and im so glad I found your site 😀
@Julie, you had to go and be in Canada, right? 😉 Yes, the Radian should fit in the Patriot, but if you put it in an outboard position instead of in the middle, there may not be room for someone to sit in the front seat. I was going to suggest the Chicco NextFit, but I don’t think it’s in Canada yet. I do know that the Peg Perego Convertible is and that’s a good carseat for front-to-back tight spaces. Check out Kecia’s blog on finding carseats for fitting smaller back seats: https://carseatblog.com/22818/the-ultimate-rear-facing-convertible-space-comparison-review-size-matters/ . Since your ds is in the 75 percentile, that means he’s bigger than 75 percent of other babies his age, so he’s a big guy (my ds was always over 100%, sigh). You’ll be spending money on clothes and carseats, my dear :D.
“@Dino, just chant, “It’s only for a little while, it’s only for a little while.” LOL!”
– so true! LOL
Hi Heather,
thank you so much for your reviews.
I have a 4 month old DS who is just over 15 pounds and he’s in a mico cosi car seat which only goes to 22 pounds. I am in the market for his next seat.
I have a 2009 Jeep Patriot, would the Diono fit in my car? I also live in Canada so I know our standards are different then the US.
There are so many car seat options out there, im getting confused as to what is best. I want a seat that he can start now and go till he need to be booster. Currently he is in the 75th percentile for his height and weight ( not even sure that that means lol)
Any help would be appreciated.
@Angel, at the time the review was written, she was around 53.5″ tall with a short torso and was near the limits of the seat. I don’t think most kids make it to age 9 in the harness.
Thanks so very much for replying ( really like the wings) I was just worried about “the wings” as far as long time use -like you stated- wish they locked into place or went a bit higher for booster mode , can I ask how tall your 9 year old is…or if this seat will truly fit a 57 inch child -just confused about that. my 6 year old still in marathon at 6 so I think I will still get a few years in Rxt just wanted this to be our “last” seat, beause need to buy three 🙂 have a 6, 4 and 2 all about the same size ! Only have a 53 inch back seat!
Thanks so much for your time , very much appreciated ! You made my day answering me 🙂
Have a great day
Angel
Hi JC. Because he’s so tall, I would skip Britax seats. The newer models are on the short side and he would probably quickly outgrow them by height before weight. An RXT would be a good choice! If you go with an RXT, buy an angle adjuster at the same time since that accessory tends to sell out frequently. Diono recommends it for kids over age 1 and it gives *inches* more space for the front seat when the RXT is rear-facing. I don’t think you’ll have a problem having it behind your seat, but if your dh is like mine, he’ll probably recline his seat a fair bit and that’s what eats into a rear-facing carseat’s space. If your dh can sit more upright for a few weeks or you can drive, you should be OK. Your ds may also be OK right now with the angle adjuster if he has good head control while sleeping. You may have to experiment to see if it’s too upright for him right now.
Hello all,
My 11-month old DS is north of 30″ and 23 lbs, and over 95 and 90 percentiles for height and weight. He is outgrowing his Graco 35 and I’ve been debating between Radian RXT and Britax Marathon.
We have always used Britax for my 6-year-old daughter (Roundabout and Frontier 85) and they have worked well for her. We were going to use the Roundabout for DS but then realized it just expired so we’re back on the market looking for a convertible carseat that will last for good while, that’s when I discovered many great reviews about Radian.
My question is – We have a 2012 Toyota Sienna XLE. I have read many posts regarding pushing the front seat all the way forward in order to recline the Radian. I’m 5’2″ and I’m planning on putting Radian at the driver side since it is safer for DD to get dropped off/picked up from the passenger side. If I push the Captain chair all the way back, would it post a problem? I’m petite so it may be o.k. However, how about when my husband drives the van, which is often on weekends when we are out all together and when we take a long road trip. My husband is 5’10”. Any comments and suggestions are greatly appreciated!
@Dino, just chant, “It’s only for a little while, it’s only for a little while.” LOL!
We did manage to get the Radian behind the passenger without the angle adjuster with very little leg room up front. Will just do this until she is a little older and we can use the angle adjuster. We also washed cover by hand and hung to dry. Thanks very much!
@Angel, you should never remove part of a safety seat that the manufacturer doesn’t specifically allow. The main feature of buying the RXT is the wings, so if someone doesn’t like the wings, this seat isn’t for them.
@Dino, the angle adjuster is billed for use with kids older than a year because it puts them at such an upright angle. If your child doesn’t sleep in the car, I might consider it, but the main risk would be head slouch from poor recline. Diono recommends either hand-washing or washing in a front loader washing machine on a gentle/hand-wash cycle and hang to dry. I’d roll it in a towel to remove excess water.
Also what is the best way to wash a Radian seat cover? Throw in washing machine and hang dry, or can it go in the dryer? We bought the car seat in 2010.
Can a 7 month old that is very large (in size 18-24 month clothes) use the Radian RF with an adjuster? It is the only way it fits in our VW Golf behind the passenger seat. When our older daughter was a baby we had the Radian in the middle of the back seat, but I don’t want them being side by side.
Hoping someone will read email…read that most don’t like the “headwings” in booster mode ? Is ths something that c an possibly be removed later at that point making it a 120 ? Am I crazy …maybe that would be totally unsafe but seems like a answer ? [email protected]
@Lauren, double-check that you’re aiming for the top harness slots. The Radian has some of the tallest slots on the market for a convertible so it actually is a very good seat for tall kids.
@Ariel, I guess it’s a YMMV kind of thing with the harness adjuster. Some seats have adjusters that pull as smoothly as silk and others are more of a tug, tug. Some are virtually unmovable. I’d say the Radian isn’t bad, but my experience with it is that you’ll need some tugs to get it snug. You definitely won’t break a sweat doing it, lol.
When you say the harness needs a tug tug tug, is it hard to tighten? I currently have the Graco My Ride 65 and the thing I like least is how hard it is to get a snug fit. I can never seem to find the right angle to pull to make it tighter. I want a tall shell so we can RF as long as possible, but I need him to be snug too.
Just wanted to point out that this is NOT a good seat for tall kids in a harness. DD is 27m and 37-38″ (not exactly sure), and we’re already having to move to the top harness slot FF. Downside is, I can’t access the top slot. The wing portion prevents the front & back of the top harness slot from connecting. I’ve emailed Diono about this in case our seat is just defective or something, but yeah, at 27m, we have to change seats bc her shoulders are dangerously close to being above the top usable harness slot on this seat.