[jaychoy912]

Can I borrow the innermost LATCh from the side seats to install car seat in the middle seat?

[Orient330iNYC]

no.
if you are installing in the middle you should be using the seatbelt to secure a child seat

if the car doesnt have center latch connectors you should not borrow from the two sides, the spacing is incorrect.

would it work? maybe. but this is the last place you want to find out that guess is wrong.

[jaychoy912]

thank u!

[Sportstick]

I disagree. The pull/strength test is the same for all anchors; that is not a guess. The issue is fit, and it is most likely that your child seat would not fit. But, if your child seat happened to fit PROPERLY, there is no inability of the LATCH anchors to perform the same job. LATCH will perform better than a center seat belt if the spacing and fit are proper for your child seat. In fact, placing your child in the middle improves their safety with added protection from side impacts. If your child seat does not fit properly in the center with LATCH, the right side rear seat has fewer side impacts than the left side. The reverse is true in countries with right hand drive, if you think about intersection events.

[AlpineWhite_SJ]

Originally Posted by Sportstick

If your child seat does not fit properly in the center with LATCH, the right side rear seat has fewer side impacts than the left side. The reverse is true in countries with right hand drive, if you think about intersection events.

People Also typically use passenger side because it’s easier to unload on curb side of the car when parked. Overall, using a car seat in the center position is more optimal for crash protection, regardless of whether you use Latch or belt if done properly. You shouldn’t borrow a left and right latch connector even if the tethers reach - you’re exposing the belts to forces at angles and lengths they weren’t designed for.

[Sportstick]

Originally Posted by AlpineWhite_SJ

You shouldn’t borrow a left and right latch connector even if the tethers reach - you’re exposing the belts to forces at angles and lengths they weren’t designed for.

The LATCH anchor does not "know" where it is or to what pair it belongs. The point already made is that it must fit properly. If the attachment hardware on the child seat fit the LATCH anchors properly, and not squeezing only into their corners, the forces of impact are the same as if placed right or left. This issue cannot be solved here until the OP observes the actual location of the child seat attachments relative to the LATCH anchors.

As to the tether belt testing:

https://www.nhtsa.gov/sites/nhtsa.do.../tp-225-01.pdf

Note Figure 2 for reference.

[AlpineWhite_SJ]

Originally Posted by Sportstick

The LATCH anchor does not "know" where it is or to what pair it belongs. The point already made is that it must fit properly. If the attachment hardware on the child seat fit the LATCH anchors properly, and not squeezing only into their corners, the forces of impact are the same as if placed right or left. This issue cannot be solved here until the OP observes the actual location of the child seat attachments relative to the LATCH anchors.

As to the tether belt testing:

https://www.nhtsa.gov/sites/nhtsa.do.../tp-225-01.pdf

Note Figure 2 for reference.

The point is that you’re changing the geometry of the car seat anchor belts and anchors in relation to both the seat and anchors, which is critical per your link. Even if the anchor belt CAN reach, it doesn’t mean it should be used. OP doesn’t need to check the placement, BMW already has. Which is why the manual specifically says not to use a right and a left inner latch anchor for center position. If OP cares about center placement he should use the lap belt instead of the latch anchors.

[Orient330iNYC]

Originally Posted by Sportstick

I disagree. The pull/strength test is the same for all anchors; that is not a guess. The issue is fit, and it is most likely that your child seat would not fit. But, if your child seat happened to fit PROPERLY, there is no inability of the LATCH anchors to perform the same job. LATCH will perform better than a center seat belt if the spacing and fit are proper for your child seat. In fact, placing your child in the middle improves their safety with added protection from side impacts. If your child seat does not fit properly in the center with LATCH, the right side rear seat has fewer side impacts than the left side. The reverse is true in countries with right hand drive, if you think about intersection events.

latch has lower load limits than using a belt. my nuna rava's recommended install is via belt, the load limit with latch is 40lbs, 65lbs with the seatbelt.
i believe the federal limit for latch is 40lbs.

latch was designed to reduce installation error vs performing better than the seat belt.

i dont believe a single car or car seat manufacturer will endorse using a latch connector from each side for a position that was never equipped with a latch connection.

https://thecarseatlady.com/vehicles/...o-forbid-this/

https://carseatblog.com/31033/borrowing-latch-anchors/

and from the X3 owners manual:

It is not recommended to use the inner lower anchors of standard outer LATCH positions to fasten a child restraint system on the middle seat. Use the vehicle safety belt instead for the middle seat.

[Sportstick]

Originally Posted by AlpineWhite_SJ

The point is that you’re changing the geometry of the car seat anchor belts and anchors in relation to both the seat and anchors, which is critical per your link. Even if the anchor belt CAN reach, it doesn’t mean it should be used. OP doesn’t need to check the placement, BMW already has. Which is why the manual specifically says not to use a right and a left inner latch anchor for center position. If OP cares about center placement he should use the lap belt instead of the latch anchors.

He can actually use both, if the seat is compatible. Whether it is or is not, I don't know, but I don't agree with ruling it out a priori and possibly failing to use the belt properly or default to a side position. If we read the history of LATCH, we find that it came about (orginally called ISOFIX) to assist with reducing the rampant erroneous installations by many parents. That concerns continues, as using the proper path and eliminating all slack remains a challenge. The range of negative recommendations involves adhering to FMVSS certification (they also don't recommend a range of mods owners implement) as well as the foreseeability of user error and the product liability issues which attach to that. That is an entire other universe of rationale for what they do/do not want to say that will one day wind up in front of a jury in a failure to warn action.

The linked test protocol provides an assessment to determine if the tether falls within the tested range which is another decision factor.

If OP is a well-trained installer with a belt, and uses the knee technique to compress the child seat into the car seat, takes up all slack, and uses the proper path (many fail at at least one of these), then he can have the best of both worlds.

[AlpineWhite_SJ]

Originally Posted by Sportstick

He can actually use both, if the seat is compatible. Whether it is or is not, I don't know, but I don't agree with ruling it out a priori and possibly failing to use the belt properly or default to a side position. If we read the history of LATCH, we find that it came about (orginally called ISOFIX) to assist with reducing the rampant erroneous installations by many parents. That concerns continues, as using the proper path and eliminating all slack remains a challenge. The range of negative recommendations involves adhering to FMVSS certification (they also don't recommend a range of mods owners implement) as well as the foreseeability of user error and the product liability issues which attach to that. That is an entire other universe of rationale for what they do/do not want to say that will one day wind up in front of a jury in a failure to warn action.

The linked test protocol provides an assessment to determine if the tether falls within the tested range which is another decision factor.

If OP is a well-trained installer with a belt, and uses the knee technique to compress the child seat into the car seat, takes up all slack, and uses the proper path (many fail at at least one of these), then he can have the best of both worlds.

It has nothing to do with the seat - seat instructions tell you to follow your car’s guidelines and the BMW manual says don’t do it. It’s really not that hard to understand.

[jaychoy912]

So I'm attempting to install the car seat base for infant rear facing car seat in the middle seat with seat belt; however the seat belt connector/buckle for the middle seat is loose compared to the ones on the side seats. This is preventing the car seat base from being tightened against the seat and it will move significantly side to side. Anyone else run into this issue?

[Orient330iNYC]

Originally Posted by jaychoy912

So I'm attempting to install the car seat base for infant rear facing car seat in the middle seat with seat belt; however the seat belt connector/buckle for the middle seat is loose compared to the ones on the side seats. This is preventing the car seat base from being tightened against the seat and it will move significantly side to side. Anyone else run into this issue?

is the seat belt latch hitting the belt routing before you can pull the slack out?

you can twist the buckle end up to 3 twists to shorten it. IIRC the middle position buckle extends enough above the seat height to cause an issue for a low belt routing seat.

this seems to be fairly common as a rule of thumb for cps certified technicians but i would seek out guidance from a local expert to check the install and the method.

[Sweet_Assist]

Originally Posted by jaychoy912

So I'm attempting to install the car seat base for infant rear facing car seat in the middle seat with seat belt; however the seat belt connector/buckle for the middle seat is loose compared to the ones on the side seats. This is preventing the car seat base from being tightened against the seat and it will move significantly side to side. Anyone else run into this issue?

What car sear are you using?I had trouble with the Nuna Pipa, switched to UB Mesa and it worked.

[jaychoy912]

thanks for suggestions.
I twisted the buckle and that seemed to help a bit; however the seat base still moves side to side more than an inch despite making the belt taut. It is a peg perego viaggio 4-35
has anyone tried nuna rava convertible seat? i have that one as well but not ready to transition to it yet

[AlpineWhite_SJ]

Originally Posted by jaychoy912

thanks for suggestions.
I twisted the buckle and that seemed to help a bit; however the seat base still moves side to side more than an inch despite making the belt taut. It is a peg perego viaggio 4-35
has anyone tried nuna rava convertible seat? i have that one as well but not ready to transition to it yet

When you’re pulling it tight, are you putting a knee with all your weight on a corner point? You’ve really got to compact the seat and cinch the belt to get it properly tight so it doesn’t move. Not sure if Canada’s equivalent of Highway Patrol offers an inspection service, but if they do, it’s worthwhile to have them inspect it and show you how it’s done.

[jaychoy912]

Originally Posted by AlpineWhite_SJ

When you’re pulling it tight, are you putting a knee with all your weight on a corner point? You’ve really got to compact the seat and cinch the belt to get it properly tight so it doesn’t move. Not sure if Canada’s equivalent of Highway Patrol offers an inspection service, but if they do, it’s worthwhile to have them inspect it and show you how it’s done.

Yup, putting my weight on it. It's strange, not having the same problem with my other car which is a Subaru. Was able to install with seat belt fine. With the X3 I am having the same issue on the other seats as well, not just the middle seat; not able to tighten sufficiently with seat belt for some reason. Works with LATCH connectors but I would really like to use the middle seat if possible.

[odysseus]

Originally Posted by Sportstick

I disagree. The pull/strength test is the same for all anchors; that is not a guess. The issue is fit..

"Borrowing" an anchor from the sides can lead to greater angles and more force exerted on the LATCH connector.

Scenario 1: Straight in latch connector.

Let's imagine emergency braking or a crash leads to peak force 100 lbs at the LATCH connector.

Scenario 2: Belt at 45 degree angle.

With some simple math you can see the force at the LATCH connector will be about 41% higher (hypotenuse of a right triangle with 45 degree angles will be sqrt(2) times the length of a side). You'd get 141 lbs of force pulling at each anchor.

A calculator for climbing purposes here:
https://www.ropelab.com.au/two-point...-calculator-2/

[huggy509]

Originally Posted by Orient330iNYC

latch has lower load limits than using a belt. my nuna rava's recommended install is via belt, the load limit with latch is 40lbs, 65lbs with the seatbelt.
i believe the federal limit for latch is 40lbs.

latch was designed to reduce installation error vs performing better than the seat belt.

i dont believe a single car or car seat manufacturer will endorse using a latch connector from each side for a position that was never equipped with a latch connection.

https://thecarseatlady.com/vehicles/...o-forbid-this/

https://carseatblog.com/31033/borrowing-latch-anchors/

and from the X3 owners manual:

It is not recommended to use the inner lower anchors of standard outer LATCH positions to fasten a child restraint system on the middle seat. Use the vehicle safety belt instead for the middle seat.

I agree
Follow manufactures advice only, at least this will have been tested and probably crash tested.
Last thing you want after a collision, especially with kids, is to discover the advice someone gave you on a forum against manufacturers instructions was wrong