Using latch with seatbelt against guidelines?

[paintedbison]

My DD is over 40lbs in a britax frontier. Twice I have noticed that the seatbelt has come unlatched. She is in the middle of a minivan, and I have two older children climbing through to the back constantly. I make every effort to make sure that I check before we take off that the buckle is still fastened. However, if I were to forget just once and the seatbelt had come unlatched, it would be tragic if we were in an accident.

I'm tempted to hook the latch in as "back up". She is over the weight limit for latch. However, I would be considering the latch as a back up system. I just have a hard time believing that having the seatbelt and latch both in place could cause an increased risk.

What do you think about doing this?

 

[ketchupqueen]

It's not a good idea. Using both is untested or failed testing; for all we know it could cause the seat to fail.

However, there are a few things you can safely do to prevent unbuckling. One is to flip the buckle stalk backwards so it's hard to unbuckle.

Or, you can do this:

 

[Jessica61624]

We use the plastic cup also with my middle seat. It works perfect. I wouldnt use the lower anchors with the seat belt.

For mine I cut the bottom of a plastic bottle. I think it was a sobe bottle. Ans taped it.

 

[MommyShannon]

I turn the bottom buckle 180 degrees so its hard to push the button. DD is in a FR harnessed sometimes and boostered sometimes so she has accidentally unbuckled the seat when she was harnessed to get out. Since flipping it she has complained half asleep that she can't get unbuckled and I remind her she's harnessed.

 

[Jeni-GAcpst]

What type of minivan? Some allow up to a combined weight of 65lbs, which would be a 45lb child in a frontier.

I agree with the others. The concern is both that you're depending on latch over the limit - and the issue of using both belts at the same time. The belts are designed to flex and sway to help reduce crash forces on the child. Double the belts holds the car seat with double the force, which could cause the frontier belt path to bend or break as well as maybe increased injuries to the child due to the fact that the belts together aren't able to flex as far. Some techs hypothesize too that if the belts were a slight bit different tightness, it could cause the seat to spin during a wreck.

There are so many possibilities for damage due to using both seat belt and latch - plus there are several options for keeping the seat belt safely buckled. May as well go for the safer option