Britax Marathon 70 Review – Part I


I’m going to break the entire Britax Marathon 70 review into smaller bite-sized pieces. Partially because I don’t have a lot of time today, partially because it’s 100 degrees outside right now and partially because I know everyone is anxiously awaiting more info and I don’t want to keep you waiting longer than necessary.

The Britax Marathon 70 is a convertible child restraint rated for children 5-40 lbs in the rear-facing position and up to 70 lbs in the forward-facing position.  It has a listed height limit of 49″ tall but since all children are proportioned differently, it’s possible that it may be outgrown before that listed height limit is reached.  Since many of our readers are familiar with the original Britax Marathon model, many of my comments will be comparative.

The new Marathon 70 has a deeper seat pan so it will provide more leg room/thigh support than the original. The outer crotch strap position measures 8″ so it offers considerably more room in that area than the original model did.  The side walls are deeper and wider too so that’s a nice improvement as well.  I promise exact measurements and more pics in part II of the review, which is now posted HERE.

Forward-facing installation with LATCH in the captain’s chair of my minivan was a breeze. 15 seconds flat and the seat was installed rock-solid with the lower anchors and top tether.  Honestly, it just doesn’t get any easier that that.  It was too hot to try any other installs at that moment but I promise more installation comments in a few days.

Next, I tried my just-turned-6-year-old in the seat.  He is currently 50 lbs and 47″ tall.  Unfortunately, I think he has slightly (maybe a half inch?) less room height-wise than he has in his old Decathlon which has the same shell as the original Marathon and Roundabout 50 models.  Considering that most 6 year olds don’t ride in convertible seats I really don’t see this as a major problem. The new Marathon 70 should still get most average-sized kids to the age where they can safely transition to a belt positioning booster seat.  Off-the-chart and long-torso children will always be the exception.

Here are the pics of DS2 in the Decathlon:

  Decathlon shell height  DC top harness slots


Marathon 70 installed in the upright position:

  Marathon 70  Marathon 70 top harness height  Marathon 70 top harness height

For more info see Part II of the Marathon 70 Review posted HERE.



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