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Diono Radian 3QX and 3QXT All-In-One Convertible Car Seat Review


The Diono Radian Q series offers all-in-one convertible car seats that are brand new and ready to make life easier. Moreover, they are created to fit three across in the back seat, so everyone gains more space with comfort and safety in mind.

Start with infants and stay in the same Diono Radian 3QX or Diono Radian 3QXT car seat for ten years so you don’t need to keep making new purchases.

Image of Diono Radian 3QX Latch, All-in-One Convertible Car Seat, Red Cherry

Diono Radian 3QX Overview

Car seats have reached new heights in technology and improvement as you can now buy car seats to last for not just one phase, but for multiple. Car seats shifted to turning into booster seats, and each step a car seat reduces saves you time searching for the next seat and money purchasing new seats.

With the Diono Radian 3QX, you get one seat to cover three stages for complete newborn protection all the way up to a child in a booster seat protection. 

Safety

Diono works hard to keep your baby safe from the day she is born all the way until your baby is no longer a baby and ready to sit in a car unassisted at ten-years-old. An automotive-grade high steel core all throughout the car seat shield and protects your infant. Next, add in one-click connection to the seat base and a rebound bar for even more security. 

Safe+ engineering ensures rigorous testing to ensure the seat will keep your most precious cargo safe. It even comes with a special headrest with the latest European Side Impact technology to keep your child’s head contained even in a car accident. They do this by increasing the size 22 percent compared to previous models.  

Lastly, Safe+ also means your child gets side impact protection with six layers. Those layers include EPS, EPP foam, high-density plastic, and steel reinforcement for side safety from impact without reducing the space available in your car. 

Stages

Newborn

Image of Diono Radian 3QX Latch, All-in-One Convertible Car Seat, Red Cherry

One unique feature of the Radian 3QX is it comes with a newborn travel high wedge to create a near lie-flat travel position for infants. This new feature helps to reduce head slumping and keep airways open. When your baby outgrows it, simply remove the wedge and move onto the next stage. 

Next, the newborn stage uses a 2-in-1 infant positioning liner. Keep newborns surrounded in a comfortable layer of padding, then use it for your toddler, too. Once your child ages out of her toddler years, remove the liner and move on to the next stage. 

Finally, a Safe+ steel anti-rebound bar offers a one-click connection to the seat base. The bar reduces rebound rotation by 50 percent in a car accident collision. Also, the bar helps to provide more legroom when rear-facing.  

Toddler

Image of Diono Radian 3QX Latch, All-in-One Convertible Car Seat, Red Cherry

Use the seat for toddlers in the rear position until they reach fifty pounds. Once your baby reaches the height or weight limit, turn the seat around and use it front-facing with a slight recline and the infant liner. Tots can use the forward-facing mode after one year of age or 22 pounds, but it’s best to keep them rear-facing as long as possible. 

Image of Diono Radian 3QX Latch, All-in-One Convertible Car Seat, Red Cherry

Child 

Image of Diono Radian 3QX Latch, All-in-One Convertible Car Seat, Red Cherry

The child stage is actually two stages. Just like with your toddler, your child can sit front facing in the car seat, although, you will want to take out the infant insert out and change the reclines. Moreover, do not forget to adjust the headrest and the seat belt as well. 

The final stage is reserved for when your child is ready for the booster seat. At this point, you need to remove the 5-point harness so your child can use the high back booster correctly. You do not get the option of taking the high back booster portion off to use just the booster seat alone without the back. 

Seat & Harness

Image of Diono Radian 3QX Latch, All-in-One Convertible Car Seat, Red Cherry

The seat and harness both come with tons of padding and cushion for the ultimate in luxurious comfort. You can take the inner newborn liner out and still have a comfortable place for your child without taking up huge amounts of spaces in the car. It also comes with an extra headrest, not just for safety, but to keep kids heads from drooping while sleeping. 

Another valuable feature of the car seat is memory foam cushioning. We all know and love our hybrid or full memory foam mattresses and pillows, and now babies can too! Even better, memory foam absorbs shock and retains its shape making it comfortable every time without ever wearing out. 

Diono Radian 3QX Specifications

  • Comes in six colors including black, gray, blue, pink, red, and yellow
  • Rear-facing for 4 to 50 pounds
  • Forward-facing 22-65 pounds 
  • Booster mode 40-120 pounds
  • Seated torso heigh 7.5 to 16.5 inches
  • Maximum height up to 57-inches
  • Sits 3 across the backseat 
  • The seat weighs 25.8 pounds
  • Includes infant insert  
  • Newborn travel high wedge
  • Adjustable headrest with 12 height positions
  • Steel anti-rebound bar 
  • Steel core
  • Comes with 1 cup holder 
  • Memory foam 
  • Machine washable cover

Diono Radian 3QXT Specifications

  • Comes in six colors including black, gray, blue, pink, red, and yellow
  • Rear-facing for 4 to 50 pounds
  • Forward-facing 22-65 pounds 
  • Booster mode 40-120 pounds
  • Seated torso heigh 7.5 to 16.5 inches
  • Maximum height up to 57-inches
  • Sits 3 across the backseat 
  • The seat weighs 25.8 pounds
  • Includes infant insert  
  • Newborn travel high wedge
  • Adjustable headrest with 12 height positions
  • Steel anti-rebound bar 
  • Steel core
  • Comes with 1 cup holder 
  • Memory foam 
  • Machine washable cover
  • Includes extra newborn protection insert 
  • Comes with newborn harness pads
  • Side impact management pod

Comparing the Diono Radian 3QX vs 3QXT All-In-One Convertible Car Seat

Image of Diono Radian 3QXT Latch, All-in-One Convertible Car Seat, Blue Sky

Similarities

The Diono Radian 3QXT is a slight upgrade from the Diono Radian 3QX, as it has extra protection on the sides and a newborn insert. Every other aspect of the two car seats is exactly the same from the color choices, to the newborn base wedge, and all of the safety features you know and love.

Differences

The Diono Radian 3QXT has four stages, while the 3QX has only three stages for a negligible price difference. Both car seats come almost exactly the same, with the main difference being the infant liner. The 3QXT has an extra infant liner that comes with a newborn protection insert that forms like a nest around your baby along with added harness pads for the smallest passengers. 

If you need a preemie car seat, then you may want to consider the 3QXT because of the extra protection for newborns. 

With the insert, you get super soft padding for extra comfort and shock absorption. It’s made with energy-absorbing material for protection from shifting or hard braking. Mind you, this insert is only good for the first few months of the baby’s life but goes a long way in keeping the baby from jostling around in a moving vehicle so they can sleep, and you can rest assured in their safety. 

Next, the 3QXT comes with side impact pod for extra protection to ensure your baby is absolutely the safest, and it’s located on the side of the car seat facing the same direction as the door of the car. It’s engineered to channel excess energy on the back of the car seat in the event of a side-impact car accident.

On the 3QX, the side protection offers six layers of interlocking EPS & EPP foam coupled with the high-density plastic and steel reinforcement, but with the upgraded 3QXT, you get eight layers of protection. 

Lastly, the 3QXT comes with a little bit more testing than it’s counterpart the 3QX. This means the car seat meets the required US FMVSS 213 for two times impact force, and it has also been tested for rear impact to ensure rigorous quality to keep your baby even safer. If you want the absolute safest car seat, you want the 3QXT. 

Function 

As this is a convertible car seat, it does not come out of the car and go into a stroller. If you are looking for a stroller to work as a part of your infant travel system, consider a dedicated infant car seat. What’s great about all-in-one car seats is they are dedicated seats you don’t need to worry about adjusting once they are set up in your car.

Infant car seats do not last for 10 years like the Radian 3QX and 3QXT and require switching to new car seats with every stage. Both of the above car seats will stay with your child until they are out of a car seat and booster completely. However, neither function as a backless booster seat alone and kids must use the highback, which many older children do not enjoy. 

Moving an all-in-one car seat through an airport can be challenging, and you may want to consider getting a rolling cart for the car seat. If you travel a lot or need to switch car seats to different vehicles often, you may want to consider purchasing a second car seat. 

The last point about the function of this seat is that it does not recline at all in either model. This is why it comes with a wedge for infants because the seat offers only one position.

However, both models include a removable cupholder so parents can leave a drink in the back with their baby without theatrics!

Comparison to Other Carseats

Many name brands are making car seats to last for ten years, but which is best, what are the different functions, and should you consider a different car seat over the Diono Radian Q Series.

First, we will look at another popular option by Diono before delving into some of the other popular brands. 

The Diono Radian 3QX and 3QXT vs. Radian 3RXT

Image of Diono Radian 3RXT All-in-One Convertible Car Seat, Black

On the first glimpse, the Diono Radian 3RXT looks very similar to the Q Series. However, there are a few differences with a slightly different shape and a different infant insert. The main difference, though, is the 3RXT does not have the rear-facing steel anti-rebound bar. 

Another difference is the 3RXT works for infants 5 to 50 pounds while the Q Series works for 4 to 50 pounds giving one extra pound to premature infants. The 3RXT also doesn’t have the newborn wedge, a steel core, side-impact protection, rear-impact protection, or extended sidewalls. The newer Q Series also comes more rigorously tested for rollover and rear impact, as well as 2x impact force, protected. 

The similarities between the two seats aren’t too surprising as they are made by the same brand. Although both do sit three across and come with the same great quality you would expect from the brand, but in the 3RXT, you can expand the seat width a little bit if you don’t need to fit three across. Both series are made with automotive-strength steel with dual spines with business class comfort. 

Otherwise, you get memory foam, low seats, anti-slip harness, a cup holder, side-impact, and 12 headrest positions. While your baby will love and enjoy the comfort of the Radian 3RXT, they won’t get the newest technology, meaning they can get a better and safer ride from the 3QX and an even safer ride from the 3QXT. 

The Diono Radian 3QX and 3QXT vs. The Britax One4Life

Image of Britax One4Life ClickTight All-In-One Car Seat 10 Years of Use Infant, Convertible, Booster 5 to 120 Pounds - SafeWash Fabric, Eclipse Black

You know how the Q Series by Diono functions, but let’s take a closer at how the Britax One4Life compares to the high quality of the Diono brand. The Britax comes with several unique safety features not found in the Q Series by Diono.  While both have a high strength steel frame, the Britax offers a safe cell technology that crumbles in the event of an accident to absorb crash energy and keep your baby safe.

Another dramatic difference between the two brands is the Britax car seat offers 15 headrest positions instead of only twelve, making it a better option for taller families. You even get recline options, including nine quick-push for the most comfortable fit for your child. Since many kids like to fall asleep in the car, this is an extremely necessary feature. 

The Britax One4Lift also comes with two dishwasher safe cupholders instead of just one. Moreover, the brand wants your baby to breathe and uses cooling and ventilated mesh to improve airflow. However, the Diono Q-Series uses memory foam to cradle your baby, which the Britax seat does not. Either seat will grow with your baby, but the Diono starts as early as 4-pound preemies while the Britax starts at 5-pounds. 

Last of all, you don’t need the Diono infant wedge with the Britax One4Life, thanks to the multiple ways to recline the seat. They also use patented click tight installation, which Diono hasn’t provided yet.

The One4Life weighs about 5-pounds more as well and comes with fewer color options, but the real main potential issue with the One4Life is it’s not designed to allow for three car seats across, which is the key selling point for the Diono Q Series. 

The Diono Radian 3QX and 3QXT vs. Graco 4Ever DLX 4-in-1 Car Seat

Image of Graco 4Ever DLX 4 in 1 Car Seat | Infant to Toddler Car Seat, with 10 Years of Use, Joslyn

Graco may market better and more than Diono, but let’s find out if their Graco 4Ever Car Seat meets up with Diono’s standard.

Like it’s counterparts, the Graco 4Ever allows for use from 4 to 120 pounds, which is the only other car seat on this list so far for preemies up to preteens. The brand also takes great strides in protection as its seat is ProtectPlus Engineered to help protect against front, side, rear, and even rollover crashes. 

Honestly, the only downside of the Graco car seat is how much space it takes up in the car, as you most definitely cannot fit three across because of the extra space and the dual built-in cupholders.

One other possible downside though, is the Graco car seat only rear faces to 40 pounds instead of 50, which may be beneficial to many parents.

Over the course of ten years, you can use the car seat rear-facing without the need for a wedge, then switch to forward-facing with the harness, then use it as a high back booster before switching to the last mode of a backless booster. Graco thinks of everything, too, as the cover comes off rapidly for easy washing, and it has an integrated belt lock-off for added security. Moreover, the car seat offers six reclining positions for ultimate comfort. 

Furthermore, you get rubberizes fuss-free harness storage for a no-slip grip getting your baby in and out of the seat. Integrated harness storage also makes your life easier. Graco focuses on safety but also on ease of use for parents, whereas Diono focuses on safety and fitting three across, so whichever is more important to you would help you decide the better option for your family. 

The Diono Radian 3QX and 3QXT vs. Evenflo Platinum SafeMax All-in-One Car Seat

Evenflo Safemax Infant Car Seat

Right away, you will notice the Platinum SafeMax All-in-One Car Seat by Evenflo doesn’t save your car space for three across. If you only have one baby, then you may not find this concerning, but parents with multiples want to maximize car space. Beyond the stylistic differences with different color options, the seats look relatively the same.

Next, the Evenflo options is definitely a little less spendy despite its ultra-comfortable appeal, but it’s the only option by Evenflo to go up to 120 pounds. The Evenflo option also doesn’t go down to 4 pounds for preemies. Moreover, the Diono options offer six or eight layers on the headrest, while the Platinum SafeMax only offers four layers, which is more than sufficient, but some parents want that extra few layers of padding. 

Evenflo does go out of their way to make sure proper installation and safety are their top priority. They use SureSafe installation for easier usage and fit in your car. They also roll test their car and make sure to protect against impact with shock-absorbing material. Evenflo are two times as safe as needed by the Federal Crash Test Standard to test for structural integrity, restraint system, aircraft usage, and temperature. 

The Platinum SafeMax doesn’t quite meet up to the benefits of the Diono Q Series, though, as it only has five headrest positions and no memory foam. Diono offers more harness covers for added chin protection too. It does, however, offer temperature right performance fabrics, dual built-in cupholders, and easy-adjust harnesses.  

The Diono Radian 3QX and 3QXT vs. Chicco Fit4 4-in-1 Convertible Car Seat 

Image of Chicco Fit4 4-in-1 Convertible Car Seat | Easiest All-in-One from Infant to Booster | 10 Years of Use - Stratosphere

Chicco makes excellent baby products, but their largest all-in-one car seat doesn’t go up to 120 pounds like all of the other options on this list. As a matter of fact, their rear-facing only goes from 4 to 40 pounds, too, which accommodates preemies but doesn’t go up to 50 pounds like the Diono Q Series.

Otherwise, the Chicco Fit4 4-in-1 Convertible Car Seat is a decent option, but it’s roughly the same price with less weight allowance but with other advantages. 

Their car seat comes with a custom Fit to Grow 4-stage construction for the seat with removable layers for the best fit for each stage. Next, they offer nine positions of recline, meaning the car seat doesn’t need the infant wedge for the best fit for babies, and children in every size can enjoy more comfort instead of sitting up straight. Chicco also uses a SuperCinch LATCH tighter for four times the force to get a tight and secure fit without tons of effort. 

As for safety, the Chicco uses a steel-reinforced frame and seat belt locking systems for safety. It also uses Duoguard, which is two layers of rigid shell and EPS foam to provide side impact protection for the whole body. Moreover, the headrest may have less cushion and only 10 positions instead of the 12 offered by Diono. 

Chicco focuses on ease of use for parents and comfort for babies but does not provide roll protection or testing. If this is a sticking point for you, then look at the other options before making your final decision. While the car seat should be easy to use, a focus on protection in the event of accidents should be a bigger focus. 

Final Thoughts

If you want the safest car seat with rollover protection that fits three across the back seat, you may want to consider the Diono 3QX or the Diono Radian 3QXT.

However, you do have to give up a couple of key features to get three kids across, namely integrated cupholders, and reclining seats. Diono will hopefully continue to improve their product to include at least the reclining seats for added comfort and napping in the car with their next model but otherwise offer a superior car seat with unique features the market needs. 

Adrina Palmer
Adrina Palmer
Adrina Palmer is a stay-at-home-mom to three wonderful children and a wife to an amazing husband. She has a bachelors degree in Religion from Liberty University and works as a blogger, copywriter, and reviewer. Adrina is a Christian hoping to help other stay-at-home moms find the joy and simplicity as a mother and wife. In her free time she enjoys many crafts, writing, spending time with family, and reading. She would love to hear from you!

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