Diono Radian RXT Review + Car Seat Safety Tips

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Disclosure: I received a Diono Radian RXT for review purposes. This article also contains affiliate links. We will receive a small commission if you choose to purchase through these links.

Diono Radian RXT ReviewWe hope you find this Diono Radian RXT review helpful. Please comment below if you have any questions about this car seat.

My 3 year old is a big boy, so we need a big car seat. Fortunately, the Diono Radian RXT is a 3-in-1 car seat that can be used rear facing (5-45 lbs), front facing (20-80 lbs) and as a booster (50-120 lbs). So, even my 40 lb, 3 year old boy will be in it for awhile. Thank goodness!

In preparation for doing this review I contacted Buckle Up For Love, a program within the Utah Safety Council, to see what common mistakes are made when it comes to car seat safety. Here are some of the tips they gave me:

Car Seat Safety Tips:


Visit a car seat technician in your area

I’m very glad that I went to the Utah County Health Department to get my car seats looked at. Marla, the car seat tech, helped me understand how to properly set up my particular car seats, including the Diono Radian RXT, in my particular car so that everything is done correctly.

Even after reading both my car manual and car seat manuals, I was still missing some great tips and information. For example, I can’t use the rear facing, or front facing, tether for my Diono Radian RXT because my older car doesn’t allow for that. I have a 1999 Ford Explorer, and Marla informed me that Ford didn’t add that option until 2002.

Read BOTH manuals

This is extremely important, especially if you’re using the SuperLATCH system (attach and release to the anchors with just a push of a button!). Anchors in cars can only allow for a certain amount of weight: car seat weight + child weight.

If you exceed the combined weight, your child won’t be safe in the event of a crash. Diono understands that, which is why you can only use the SuperLATCH system rear facing until your child is 35 lbs, and front facing until 40 lbs.

Register your car seat

Recalls happen all the time. If you register your car seat with the manufacturer then you will be notified right away in the event of a recall.

Diono Radian RXT Review and Installation Tips

Resist The Urge to Switch Your Child Too Soon

Before you turn your child’s car seat around to front face, or before you ditch the 5-point harness in favor of a booster seat, it is important to understand that car seat safety recommendations have been updated in recent years.

Your child is significantly safer in their appropriate car seat positioning. Diono makes it easier to keep your child safer for longer by allowing you to rear face for longer–until age 2 or 45 lbs.

Current guidelines from the American Academy of Pediatrics (AAP) are as follows:

  • Rear-facing until a minimum 2 years old, or until the child reaches the height and weight limits allowed by their car seat
  • Forward facing in a 5-point harness until the child reaches the height and weight limits allowed by their car seat. — This is often around 6 years old.
  • When they outgrow the 5-point harness position, children should be in a belt positioning booster until they are 4′ 9″–somewhere around 8-12 years of age.
  • One last point people don’t often consider is that children should not ride in the front seat until they are 13 years or older.

Beware of Aftermarket products

This tip I got from Buckle Up For Love, and also from Marla with the Utah County Health Department. An aftermarket product is something that you add to the car seat after purchasing it (i.e. seat protector, mirrors, car toys attached to infant car seat handles, etc).

I had a seat protector under my son’s car seat, but Marla informed me that unless it was made by the car seat manufacturer, and made for this seat, it could void my warranty.

Having a technician look at my car seats was really helpful!


Diono Radian RXT Review & Installation Tips

Rear facing

Diono Radian RXT rear facing weight limits are 5 lbs to 45 lbs. and up to 44″ tall.

The Diono Radian RXT is a long/tall car seat. When installing the Diono Radian RXT, you should be able to move your hand through the space between the child’s car seat and the adult seat in front. They should not touch.

Diono Radian Proper Positioning of Rear Facing Car Seat
The one way I was able to fit the Diono Radian RXT rear facing in my car was in the middle seat. If you have a smaller vehicle you will need to check your car can accommodate this car seat rear facing.

When rear facing, the shoulder harness must be at or below the child’s shoulders.

Forward facing

The Diono Radian RXT weight limit for forward facing in a 5-point harness is 20-80 lbs with a height limit of up to 57″ tall or top of ears are above top.

When forward facing, the shoulder harness must be at or above the child’s shoulders. When installed properly, the Diono Radian RXT the car seat must be slightly reclined (via a mechanism on the bottom of the car seat) so it is not flush with the back of your car’s seat at the base of the Diono Radian RXT. (Note: For booster seat mode you do want it flush with the seat.)

Additional tips for forward and rear facing

The crotch strap must be snug against the child. Do not have it too far forward.

The car seat must not move more than an inch from side to side at the point it is harnessed to the car, i.e. seat belt, or SuperLATCH. A small amount of play is good, but no more than an inch.

Booster Seat Positioning

The Diono Radian RXT weight limit for booster seat positioning is 50-120 lbs with a maximum child height of up to 57″ or top of ears are above top of the seat. In booster positioning, the Diono Radian RXT should sit flush with the back of the car’s seat.

My Overall Opinion

The Diono Radian RXT is an excellent car seat choice. It is heavy, but that’s because it features a steel frame with aluminum reinforced sides, giving your child added protection.

Diono is having a sale on their website right now! This seat usually retails for $359.99, but right now you can get it for $299.99.


About Dallas Finnell