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Old 06-17-2013, 10:24 AM   #1
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Sofa Seat - Adding Additional 3Pt Seat Belt


I have come across this topic once or twice before but nothing within the last 3 years so I thought I would put it out there and see if anyone has had any good success. My wife and I are picking up a RB-150 Sprinter Van in about 2 weeks and somehow the absence of a 2nd 3-pt seat belt has eluded us until just recently. This becomes an issue as we have two children (4 yo and sub-1 year). I was wondering if anyone has found a good solution for adding an additional 3-pt seat belt to the sofa? We have come across a few harness like designs, but not sure how well they work. Any input would be greatly appreciated.


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Old 06-18-2013, 06:02 PM   #2
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Re: Sofa Seat - Adding Additional 3Pt Seat Belt

Hello again,

Further researching this topic I have come to the conclusion that adding a 2nd 3pt seat belt is going to be a substantial custom modification. However, I would greatly appreciate hearing how others, with children, have found ways of securing child seats and what seats (e.g. Britax Regent, etc.) or what other harnesses they may have used (e.g. 86Y Universal Harness, etc.).

Any comments would be greatly appreciated.


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Old 06-18-2013, 11:55 PM   #3
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Re: Sofa Seat - Adding Additional 3Pt Seat Belt

We have a 3 1/2 year old and a sub-1 yr old, so are pretty much in your same shoes. We've been happy with the Britax so far (I think we have Marathon and Boulevard models). I've added a tether connection point behind the seat to help secure the seat. I don't recall at what weight you are supposed to need the tether, but it certainly makes me feel better having it. That would be a pretty simple modification to add a tether anchor and could be used in the future to secure an 86Y harness.

Speaking of which, I recently ordered (2) 86Y harnesses for future use as well. I haven't installed them yet, but I think they will be a nice option for those of us without 3-pt seatbelts in the rear. I think I will use it with a booster seat that has a back on it first so that it keeps my daughter a bit more contained and would be more comfortable if she fell asleep. The Britax, while a great seat, takes up quite a bit of real estate to pack around in comparison.
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Old 06-19-2013, 01:48 PM   #4
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Re: Sofa Seat - Adding Additional 3Pt Seat Belt

That's sounds like the same plan that we have arrived at, the Britax Marathon for a more then the booster with the 86Y. I contacted Sportsmobile yesterday and asked about the "tether" anchor that they put in an unfortunately they don't add them anymore (liability reasons - which is understandable). Did you end up welding something to the frame down behind the back of the seat?
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Old 06-19-2013, 02:26 PM   #5
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Re: Sofa Seat - Adding Additional 3Pt Seat Belt

This is what I used.
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Old 07-02-2013, 10:55 PM   #6
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Re: Sofa Seat - Adding Additional 3Pt Seat Belt

I recently installed a three point seat belt in my cargo van. I started with a 2" x 4" x 1/8 inch steel plate. Then drilled a 3/4 inch hole in the center. Welded a nut over the hole and to the plate. Welded the plate to the thin second membrane on the interior of the van. Screwed the upper shoulder harness bolt into the plate. Same idea for the lower bracket. I'm not sure how safe this system is. I figure if there is enough torque to rip the bolt /plate out, the chances are that the seat belt will pierce through skin first......Hard to imagine for me, but I felt confident in it's ability to hold my fiver year old in a booster seat in place. I also used 2" x 2" x 1/8 inch plate for a "washer" to strengthen the installation of the bench seat through the floor. Let me know if you are less confident!

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