Britax Marathon 70 Review – Part III – Installation


This Britax Marathon 70 Installation Review is a continuation of review Part I and Part II.  The Britax Marathon 70Boulevard 70, Boulevard 70 CS (Click & Safe), Advocate 70 CS and the Roundabout 55 are the all new Britax convertible carseat line.

Installation comments in 2005 Ford Freestar minivan (middle row captain’s chair) with LATCH:

The Good News – Everything! The seat practically installs itself, both rear-facing or forward-facing, if you’re using the LATCH system.  Unless otherwise specified by your vehicle manufacturer – you can use the lower LATCH anchors until your child reaches 40 lbs, then you must switch to a seatbelt install.  Many vehicle manufacturers allow the LATCH system to be used up to 48 lbs so check your vehicle owners manual for guidance.  Britax recommends that the tether be used at all times.  If using LATCH in a center seating position that doesn’t have dedicated lower anchors – you can use the lower LATCH attachments on the Marathon 70 if the spacing between those lower anchors is 20″ or less and the vehicle manufacturer allows it.  The “Non-Handed” lower anchor attachments on the MA70 allow you to easily switch the connectors from the rear-facing to the forward-facing orientation.  You just slide the straps back and forth along the metal bar and attach them to the lower LATCH anchors! No more “switching” the LATCH connectors like you had to do on the original Marathon model.

Now the big question: How much room does the new MA70 take up in the rear-facing position? 

I’m happy to report that it actually takes up LESS room than the original Marathon model! Here are comparison pics of the Decathlon (similar shell to the original MA) installed in the captain’s chair of my van, then the MA70 installed with the level line level to the ground (the level line is the mid-point between the recommended 30-45 degree angle range allowed), and installed again with a single pool noodle to get it closer to the 45 degree recline that you would want for a newborn.

Needless to say, installation with LATCH in the captain’s chair of my van was as easy as possible and I was happy to see that that much hadn’t changed. The original Britax convertible models were well-known for their ease of installation.  The rear-facing install took a little longer only because I had to find a place to attach the tether connector strap to tether the seat Swedish style.

Since I already had the seat installed at a recline angle appropriate for a newborn – I put my 20″ newborn-sized doll in the seat to see how it looked.  This doll is about the size of a “big” newborn.  Harness fit with the doll (without the newborn insert that can be ordered separately from Britax) wasn’t too bad. I used the body insert pillow that came with the seat but removed the belly pad and the harness strap covers because stuff like that just tends to get in the way with a smaller baby.  You can see that the harness straps were still a bit over the shoulders but the fit was acceptable in my opinion.  If this were a real newborn baby, I would probably recommend removing the rubber HUGS pads on the harness as well. The HUGS pads are optional when the seat is being used rear-facing but they are mandatory for forward-facing use.

Next up, installation in my husband’s 2000 Honda Accord. This vehicle has top tether anchors but no lower LATCH anchors so I had to use the lap/shoulder seatbelt to install the MA70 in this vehicle.  The good news here was that the seat fit just fine in the rear-facing position even with the driver’s seat pushed all the way back.  As long as you don’t need a 45 degree recline for a newborn – there was plenty of room to fit this seat.  The bad news was that the new lock-offs (both rear-facing and forward-facing) gave me a hard time.  You have to clamp them shut while there is still slack in the seatbelt and then attempt to pull all the slack out of the belt thru the closed lock-off.  I found this to be counter-intuitive as well as counter-productive.  Unfortunately, there is no way around this since the lock-off won’t shut if the belt is “pre-tensioned”.  The good news regarding the bad news is that the lock-offs are optional if your vehicle seatbelt can be locked (locking latchplate, switchable retractor, etc).  In the end,  I was able to get better, tighter installs both rear-facing and forward-facing by bypassing the lock-offs and just locking my seatbelt using the switchable retractor.

Here is a video demonstrating rear-facing installation with lap/shoulder seatbelt using the lock-offs:


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