Inertia seatbelt function

[Xplitive]

Interested in some semblance of safety in my truck. Just Discovered The front seatbelts in my ‘89 do not lock when pulled hard and quickly like a modern vehicle. Trying to avoid putting myself through the windshield during an emergency braking test.
How does the inertia reel and locking mechanism work (or how is it supposed to work)? is the locking mechanism dependent on anything else such as an electrical signal?

[babywag]

That is normal.
These are old school belts with a small pendulum they only lock when it swings due to sudden decel/braking etc.
A hard brake application(no need to lock them) will tell you if they are working.

[Xplitive]

Wow, where would the pendulum thingy be located?
I’ve previously braked hard before and nothing.

Not sure how aftermarket modern ones are set up but thinking if the newer ones have a faster reaction, that is to my advantage?

[letank]

inside the box at the base of the B pillar, it has the pendulum and the retractor... I have a pict somewhere, in the bodywork sub, or check my reply in the older post below, team grand wagoneer seat belt



As Tony said, you can pull on the belt rather fast and it does not lock up, but when you apply the brakes rather firmly the belt will lock up... and this is the difference with an aftermarket belt, I got a set to replace the driver's side because the spring for the belt tightener broke (this is in the white box, with the label do not open, photo below) , so the belt was mostly flabby. The aftermarket system is rather annoying because if you pull too fast the belt locks up

do not open

[Xplitive]

Thanks Michel.
I would be good with annoying if that meant a safer belt... and better assurance a seat belt (especially aftermarket) was going to work. Would think anyone with kids and booster seats would want the quick take up.

Got the contact info for the engineer at a seatbeltplanet and will discuss the quick take up and what makes a safer seatbelt.

[candymancan]

Good thread thanks guys i always wondered thst myself.. noticed it would lock when i braked hsrd but not if i yank it

[letank]

Thanks Michel.
I would be good with annoying if that meant a safer belt... and better assurance a seat belt (especially aftermarket) was going to work. Would think anyone with kids and booster seats would want the quick take up.

Got the contact info for the engineer at a seatbeltplanet and will discuss the quick take up and what makes a safer seatbelt.

de nada, IIRC, my replacement came from seatbelt planet... need to find the receipt to confirm:
it is a seatbeltplanet 301 16030 or # 048772 as per label on belt tag, manufactured 2016

[1979bettywhite]

I bought my replacement belts through seatbeltplanet.com. Pretty happy with them, although they are a somewhat old school belt. You have to pull them very slowly to latch as they are pretty quick to catch if you pull them quickly. Took some getting used to when putting on my seatbelt.

Part number 300 in medium beige for me (color code 38).
Retractor length was 140". Buckle length was 20", although you may be able to get by with a shorter version. But I have aftermarket seats that sit up a bit higher, so I wanted to make sure they reached.

Everything bolted up fine. I ordered the HD hardware kit (part # 950001) but wound up not using it. Just reused old hardware and some grade 8 bolts.

[Xplitive]

Awesome, thanks for the feedback on the belts!
Going to replace the original lap belts in back first as I need them for booster seats and the occasional little passengers. Meantime, reassess what’s going on with the front.