Radian 3RX

in my '94 300tdi 110 I used a Diono Radian 3RX but that's forward facing (not for a newborn) and has a proper middle row... You might want to think about buying at least 1 of these (https://www.exmoortrim.co.uk/seating/defender-load-area/loc-and-fold-right-hand.html) first, then putting a rear facing baby seat in that.

I have the Diono brand

Wife has all graycos in her SUV. I liked the diono better so went with that for my truck. Now she likes those better and also wants them for her car… sure let’s spend another $600 on car seats

Currently have a Silverado 2500 and there’s some room still, but the gladiator cab is obviously a bit smaller

I three Diono R3s. That’s about as slim as they come. Currently have a Silverado 2500 which has plenty of room. But if I downsized it would be between a Gladiator and maybe a Colorado.

We have a Nuna exec at home but we're traveling for the first time with our new diono r3. You need to purchase straps but it can be carried like a backpack. It doesn't fit rear facing in economy on an airplane, but it works rear facing or front facing for cars and it's super easy to install. We like it for what it is. Our big guy fits in it with room to Grow

We have a travel car seat - the diono r3 - and you can buy straps for it that effectively make it into a backpack. We've used it domestically and internationally and it fits on coach seats (front facing) and then you can use it rear facing for the car once you get where you're going. Every time we travel with it, we have parents stopping us and asking about it. Super light weight and easy to use!

I just went through this for my kids. I looked up gladiator boards and they recommended the Radian 3R. I bought them and I couldn’t get them tight enough for my comfort, so I returned them. I did find the answer though, with the Britax Poplar convertible seats. More expensive, but better rated, and their click tight feature made it really secure. That’s my rec. I currently have them on both ends with an infant car seat in the middle. Works like a charm.

I’ll second this! I had three Diono seats in the back row of a Subaru outback for a few years. It worked rather well!

I have 3 of these across the back of my 2015 Outback. They are a little tight to go in but sit perfectly once in place.

We had 3 Diono Radian car seats fitting in the backseat of a Subaru crosstrek. What’s tricky is when you need some to be rear facing because they lean back far. For that situation they sell a piece of foam that slides under the seat to safely adjust the angle.