Diono Rainier Review – Saved lives?

Diono Rainier 2AX Convertible Car Seat Review

We went on a spin ride!… Said my son after we got T-boned…

Everybody wants to avoid accidents as much as possible. And when it happens, you can’t do anything. Get the safest car seat you can get, and everything will be fine.


This has happened to some friends of mine. They were crossing an intersection when an inattentive driver T-boned their car. It was a vicious crash. The metal twisted and airbags deployed. Glass was flying everywhere.

The car spun around. This wasn’t a light fender bender. The car got totaled. My friend had a shoulder injury, and his little one was fine. He was cheering and said that they were in a spin ride. They were between life and death, but the car and the seat did its job.

Or I’ve heard about another accident where the car was totaled. The little boy was sleeping in the car seat as if nothing has happened. The policeman woke him up to see if he’s alright. This is how good these Diono Rainier seats are. Of course, the little one was in good shape, no injuries what so ever.

Before we get any further, let me give you a quick preview. If you want a luxury car seat here, it is. It’s convertible so it can be used from 5 pounds up to 120. It allows extended rear-facing since there’s more than enough room for your child. Steel core offers the best protection possible.

It’s the safest car seat from the Diono brand. They have upgraded the side protection so your little will be safe all the time. This car seat looks cool. You can select from 7 colors.

Let’s get this Diono Rainier review started. If you stick with me until the end, I will tell you the pros/cons. Some of them are unexpected, to say the least.

Who is the Diono Rainier 2AX Convertible Car Seat?

This car seat is ideal for parents who have big cars. Also, it’s intended for those who want to save money in the long run by having this seat from 5 to 65 pounds.

Plus, it’s for those who want to do extended rear-facing.

What can the Diono Rainier Car Seat do for you?

As you have read above, the Diono Rainier has been safely tested by parents in real situations. It has passed with flying colors. It has protected the children, and even in the worst crashes, they were unharmed.

We can safely say that it offers the best protection for the money. Besides safety, it’s a real looker. Have you seen the color choices? I mean, it’s hard to choose from all those vibrant colors. It has a fresh and clean modern style.

Since it’s a convertible car seat, you can use it from the day you bring home your child until they learn to drive. That’s a hell of mileage for the money.

I have some good news for all those parents who want to do extended rear-facing. As you know, this position is the safest of them all. With this Diono, you can do it until your child reaches 50 pounds. That’s wow.

You probably guessed that this car seat is huge, and it has one more surprise up its sleeve. It has a narrow profile. Who would’ve guessed? Thanks to this design, you can fit 3 in a row with ease.

The kids usually fall in love with this car seat. They have upgraded the head padding, and it’s one of the highest-rated ones when it comes to side-impact safety.

Diono Rainier shortcomings

All car seats have drawbacks, and Diono is no different. By getting to know the negatives, you will have the full picture. Plus it will be easier to make a good decision.

This car seat is heavy. Like most convertibles, it packs a lot of weight. Once you’ve installed it, you won’t have the motivation to move it to another car.

If you have a smaller car brace yourself, in the rear-facing mode, it takes up a lot of space. Take a look at the best car seats for small cars post, if you need a car seat for compact car.

So the front row will suffer. This is good if you want to do extended rear-facing because there’s a lot of room to grow.

It’s not the easiest installation ever. There’s a steep learning curve. If you don’t watch the videos, then expect anything between 15 to 20 minutes of sweat and cursing. So to make it as easy as possible, check those out.

Now here’s a biggie. I mean, it’s a design flaw. If you want to adjust the headrest, you will have to uninstall the car seat. I know it’s counterintuitive. In a way, it’s just dumb.

Another big issue is that smaller kids will have their head slumping while they sleep. There’s nothing really to do about it besides using the front-facing mode.

Well, these would be the flaws of this Diono car seat. What do you think are they that bad? Let’s continue with the next section.

How To Get The Most Out Of Diono Rainier 2AX Convertible Car Seat?

This car seat is throwing my usual advice out of the window. Here are my top recommendations. I advise doing rear-facing as long as possible. But it’s a bit tricky because the seat is taking up a lot of space. So who’s sitting in the front row will be squished.

My other recommendation is to place the car seat in the middle. That’s the safest spot for the child. Not if you have a smaller car that will be uncomfortable for two people. Look at the bright side; it has a narrow profile. In this case, the second safest place is behind the driver. Again it’s the same issue.

The next step is to get it installed properly. If you watch the videos, the learning curve will be drastically shorter. As always, if you want to extra sure, do ask for a second opinion from a licensed professional.

Diono Rainier 2AX Convertible Car Seat Review

  • It’s the most protective car seat from all the Diono car seats
  • It supports extended rear-facing, and it has a lot of legroom for long-legged kids
  • The car seat gives you a lot of mileage from 5 to 65 pounds
  • In rear-facing mode, it takes up a lot of room in smaller cars
  • It’s tricky to install if you haven’t watched the videos

Conclusion for the Diono Rainier Review

As you have seen, this car seat is ideal for a few parents. If you have a big car, then this will be a joy to use. It has been tested by birth parents in real commissions, and it has protected the children perfectly. What more can you ask?

We have reached the end of the Diono Rainier review. I hope this helped make up your mind. Now, if this is the right fit for you, get it soon because stocks are running low.

If you have ideas about what I should review next, do let me know in the comments section below.

Catch you next time.

Frequently Asked Questions (FAQ):

Can you fit 3 Diono Rainier?

Yes you can fit 3 across with the Diono Rainier. It’s just 17.8 inches wide.

Which Diono Radian is best?

By far the Diono Radian 3RXT is the best choice.

Does the Diono Rainier recline?

For rear facing mode the Diono Rainier has one recline position. For forward facing mode there’s no recline.

What kind of weight limits does the Rainier have?

These diono seats have wide weight limits. The lower weight limit is 5 pounds and the upper weight limit is 120 pounds. The height limit is 17 inches for torso height. The child weight range is 5-50 lbs for this infant car seat. The seat weight is 27.5 pounds.

Which is the best Diono car seat?

The best Diono car seat is the Diono Radian 3RXT.

How can you install these Rainier booster mode car seats?

Before you jump into the install make sure you read the instruction manual. Since it’s an all in one car seat it can be installed via rear-facing installation and rear-facing installation. Besides that you can use the vehicle seat belt installation superlatch system. If you want ease of use then go with the surelatch system. It is mean to be installed on the back seat. Diono seats are known for their ease of use. The belt path makes the install a breeze. You can use the shoulder belt for the best shoulder positions and you can adjust the shoulder straps according to needs. It’s true that the latch belt is easier than are the vehicle belts. Last but not least  you can use the tether anchor connectors for the best head control. You can adjust the recline angle from the harness adjuster.

Related: The slimmest car seat reviews

What kind of safety features  come with Rainier booster mode?

The booster seat or the booster mode option comes with the following. Rear-facing installation which provides the best protection for infants. Speaking of them you get an infant insert in the package. Here are some other safety features. There’s the superlatch system for easy and fast install. They are the safest seats on the market. They have a full steel frame. The steel frame will protect your child from no matter what. It has memory foam and side impact protection. The eps foam (energy absorbing) will keep your child safe. Extended rear facing for safety. Perfect head wings to keep the head from flopping. As you know side impact protection is a must have these days. The rainier has high car seat safety standards. It has a rubber base which has anti slip qualities. The side walls are deep and high for extra protection. There’s more than enough leg room for the child and the front seat passenger seat.  Another safety feature would be the steel alloy frame which means that these car seats are strong and can handle anything. The chest clip should be positioned under the armpit level.

Which car seat would be a competitor for the Rainier 2AX booster seat?

The radian rxt convertible car seats pops into mind as a great forward facing booster mode seat.

What kind of features does these Rainier 2AX car seats have?

These car seats have many features here’s the list. They have a low profile and folds flat. It has a booster seat and a booster mode and comes with great head support. Full steel frame for maximum protection. It’s super comfy thanks to the memory foam. These car seats are legendary thanks to their ease of use. Other items include: lap belt, angle adjuster, superlatch system, harness pads. It’s meant for the back seat in forward facing. The steel frame is top grade. You can’t go wrong with these car seat. The seat belt is good for booster mode. It can fold flat for easy carry so not many car seats can do this. The memory foam seat is super comfortable plus there’s the infant support cushions. The seat fabric is washing machine safe. The seat bottom is comfy and the belt path is easy to use. Other features to check out are the: harness slots (harness slot), harness straps.

Which car seat should I buy Diono Radian or Rainier?

While both car seats are good, Diono Radian offers more bang for your buck.

Last Updated on October 27, 2023 by Brian Beasley

Written by Linda Reid

Hey there, I'm Linda, a mom of three cool kids. I've tried so many car seats, you could call me a "Car Seat Detective." Searching for the perfect car seat can feel like finding a needle in a haystack, but don't worry! I've committed to researching and reviewing car seats that are super safe, cozy, and great for growing kids. Together, we'll find the perfect car seat that keeps your child safe and cozy, and makes you feel like a super-parent!