Frontier in 3rd row of Enclave - seat belt too short?

So I did the car seat shuffle in preparation for my third baby's arrival this month. I drive a 2011 Buick Enclave and have an 85lb 8YO (so he just outgrew the ability to use the harness in his Frontier85) and a 35lb 3YO who just reached the height limit for rear-facing on his Advocate so is now facing forward. My plan was to put the infant seat and the Advocate in the two second row captain's chairs and those were installed without a problem. My plan was to put the Frontier in the middle of the third row (since that is where the tether is and the 8YO is able to buckle himself so I won't have to crawl into the back of the car all the time). The seatbelt is so short in that third row that he is not able to buckle himself in. It just barely latches when I pull it out all the way. I tried using the side seatbelt (through the seatbelt guide so it would still hit him in the right place) but it is the same - just barely fits.

So, any ideas/suggestions? Would a seatbelt extender work? Why is the dang seatbelt so short?! What if an overweight person were to want to sit in the third row?! I'm so frustrated!

Also, the belt locks EVERY time, which also usually requires me to climb into the third row at 9months pregnant and also means I have to undo the seatbelt from the seatbelt guide.

I've had the Frontier (we have the '80' original version) in the 3rd row of our Saturn Outlook (Enclave twin). The center seatbelt is too short, it fit well on the driver's side (both installed as a harness seat & as a booster). The seatbelt stalk on that side is a little longer so it was easier to buckle. There were a few times when my DS was trying to buckle himself that he pulled the shoulder belt out all the way and it was locking on him (thankful for the flip-up armrests on ours or it would have been tricky to get it unhooked and fed back in).

I will say that the Frontier is a HUGE seat, especially as a booster, it's actually one of the few that fits really well in that 3rd row with the headrests. With your DS's size & age (and the side airbags in the 3rd row) I'd probably move to a NBB. Unless he falls asleep often in the car and needs the head support. I think when I tried our Recaro booster (although it might have been the Vivo, not the Performance booster) it fit fine in the center of the 3rd row. Any booster there will block looking out the back window completely though.

Seatbelt extenders are not allowed with boosters or carseats.

Is there another high-back booster that is smaller that may work better in that spot (but is still big enough for my kiddo)? I'm nervousness about not having him in a high-back booster. He doesn't need the headrest (never sleeps in the car) but they just "feel" safer?

Any other HBB will need to be in the center of the 3rd row. The vehicle headrests back there interfere with everything I've tried other than the Frontier. A Parkway may work in the center spot (I don't know if I've ever tried ours there).

The other option is to put your 3yo FF in the center of the 3rd row. Could your 8yo help him buckle?

I want to out him in the middle 3rd seat because there is a tether there and with no latch in the third row at all, I'm hoping to keep him there. That is also why I don't move the 3YO's seat to that spot - no latch. I was trying to find a HBB that may not require as long of a seatbelt as the gigantic frontier. I saw the Graco HBB (Affix). It looks like I might be able to get another inch or two using that one but I'm not sure... I looked at the Parkway too but the seating space on that looks more narrow so it may not by comfortable for him.

I wish they had put a headrest in that third row middle spot. So frustrating!

How tall is he? And what is his seated shoulder height?

If he's tall I doubt the Affix would fit him as a HBB. It's short enough that my 45" 6yo only had 1-2 more notches for it to move up.

Latch/tether on a booster don't have any effect on it's performance during an accident, they are purely to hold the booster in place when not occupied (so you don't have to buckle it in when it's empty). Also, no dedicated boosters have a tether, some have lower latch anchors but only a combo seat would have a tether that could be used in booster mode. Latch isn't any safer than a seatbelt when installing a harnessed seat. Your 3yo would be just as safe with a seat installed with Latch & tether in the captain chair as with seatbelt & tether in the 3rd row. Latch has weight limits that seatbelts don't have (in the Enclave it's 65lb seat + child weight).

Honestly, he may even pass the 5-step test in the 3rd row on the sides. I was surprised at how my 8.5yo fit on the driver's side. 5-step here: http://www.carseat.org/Boosters/630.htm
Thread with pics of my DD here: http://www.car-seat.org/showthread.php?t=268884

Thank you so much for all your help Ann! I'm going to try the 5 Step Test. He's 51 inches tall (not sure about torso measurement and he's out of town for the weekend). He had a huge growth spurt over the last 6 months and added lots of height and bulk so it may work. If not, or even just for peace of mind if it does, I will look at putting him in a backless booster on the side of one of those third rows. It makes me nervous but I guess if there are side impact airbags back there, it sounds like that's the best option I can hope for. Or go buy a limo or something with lots of seats.

He's going to be a bit peeved at me though because I don't think he will be able to see the DVD player (in the roof in the center of the 2nd row) on the sides of the 3rd row. He** hath no fury like an 8YO who can't see the DVD player!

Thanks again for your help!

The latch limit for your car is 48 lbs. child is 30 lbs so it only leaves 18 lbs to go. And the britax advocate weighs more than 18 lbs. so I would install the 3 yr old third row middle with seat belt and put your 8 yr old in a captains chair.
But you need to switch to a seat belt install with the 3 yr old.

vangelder03 said:

The latch limit for your car is 48 lbs. child is 30 lbs so it only leaves 18 lbs to go. And the britax advocate weighs more than 18 lbs. so I would install the 3 yr old third row middle with seat belt and put your 8 yr old in a captains chair.
But you need to switch to a seat belt install with the 3 yr old.

Click to expand...

This has changed within the last year or so. The old limit was 48lb, but that was only the child weight (although some seats said to only use latch until 40lb). More info about it here: http://www.car-seat.org/showpost.php?p=2438668&postcount=123

I've had a britax parkway sgl older style in the 3rd row of our 2011 traverse without a problem. It was not in the center, though. Also, I'm not a tech, but I would double check with britax about using the tether without latch in booster mode. I was told by a cs rep when I called that I needed to use the tether if it was latched as a booster. I got the impression from the conversation that it needs to be either latched and tethered or neither.