78 GMC seat belt styles

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ronniebomb

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n.e. Ill
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ron
Truck Year
1978
Truck Model
K25 Sierra Classic
Engine Size
454/t400/np203
I have a 78 GMC K25 with only 54,000 miles. It was mostly original condition when I picked it up last year.
It currently has lap belts, no shoulder harness on either side. My thinking was that in 74, GM went to the shoulder harness.
Is there a possibility that the lap belt set up was an option in the trucks for 1978? Or was the shoulder harness removed from my truck?
There is a metal plug or cap on the B-pillar where the shoulder harness would have bolted in. So it looks legit like it may have come with lap belts only?
Any information would be greatly appreciated!
thanks guys!
Ron M.
 

AuroraGirl

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400(?), 350
75 gmc my dad has is lap only. rear lap was common on the 77 cars I know, but my 80 and 78 have shoulders (truck)\

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sitting behind the seat you can see the part you click into, these are bucket seats so not sure if that made any difference

also, where was the truck made
and also is there a VIN plate on the dash by the driver by windshield?
 

Ellie Niner

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LE9 305
My 1975 GMC 3/4 ton is like that too. Believe it or not, the vehicle's GVW is determines what you get for seat belts. In vehicles that are (if I remember right) 8600GVW and up, you just got lap belts as standard equipment. Three point belts were optional. Lower GVW trucks all got the three point seatbelts, as well as a seatbelt light and buzzer as standard equipment a few years before they showed up on 3/4 ton-up trucks.
 

75gmck25

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1975
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K25 Camper Special TH350 NP203
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5.7
My ‘75 K25 (8600 GVW) had factory lap belts only, but the threaded inserts for the shoulder belts were welded into the door pillars.

I replaced all my belts with a set I bought online. They fit but do not have the plastic casing on the end that makes the belt tab stick up so it’s easier to reach. I’d like to find a set with the plastic reinforcement like a factory set, but aftermarket don’t have it.
 

AuroraGirl

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My ‘75 K25 (8600 GVW) had factory lap belts only, but the threaded inserts for the shoulder belts were welded into the door pillars.

I replaced all my belts with a set I bought online. They fit but do not have the plastic casing on the end that makes the belt tab stick up so it’s easier to reach. I’d like to find a set with the plastic reinforcement like a factory set, but aftermarket don’t have it.

Are you talking about those or something that holds in in the bench seat. ,my 1980 has little plastic pockets like an office desk for cords would have a passthrough for the buckles.

You could probably make something out of a few pieces of metal or even get a rigid mold/splint of some kind and use an epoxy to hold that shape or something creative somewhere im sure
 
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K5ride

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Steve
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1975
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C10 Stepside
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350
My light duty 1975 short bed stepside has a GVWR of 5300 lbs and came with lap belts only. The trim on the pillar did not have holes for the shoulder belt but when I replaced the trim, I found the threaded holes underneath. I'm trying to decide whether or not to install shoulder belts. The shoulder belts are much safer but it's kinda cool just having the lap belts. It makes the truck seem older...LOL. People comment all the time when they ride in it.
 

idahovette

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350
May also give younger Police Officers probable cause. They can't see the belts on and don't know our older trucks are not equipped with shoulder belts??!!!
 

ronniebomb

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1978
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K25 Sierra Classic
Engine Size
454/t400/np203
Thanks for the input y'all!
Ya know what's weird, the left-hand side male belt isn't retractable or doesn't have the hard plastic casing that would make it easier to grab and connect.
It's just lays on the floor .............. and falls out of the truck when you open or try to close the door! I really dislike having to lay the belt along the side of the seat when I get out of the truck. I have several 5 gallon buckets of car seat belts that I may have to go through to look for a retractable male belt. I just have to make sure it clicks into the the female buckle properly.
idahovette ............ I've been waiting for an officer to pull me over for that very reason!
 

AuroraGirl

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Thanks for the input y'all!
Ya know what's weird, the left-hand side male belt isn't retractable or doesn't have the hard plastic casing that would make it easier to grab and connect.
It's just lays on the floor .............. and falls out of the truck when you open or try to close the door! I really dislike having to lay the belt along the side of the seat when I get out of the truck. I have several 5 gallon buckets of car seat belts that I may have to go through to look for a retractable male belt. I just have to make sure it clicks into the the female buckle properly.
idahovette ............ I've been waiting for an officer to pull me over for that very reason!
are you sure youre using the right belt? My dads 75 both sides have a retractor and it stands pointing upward out of the "holster" whatever

It was annoying because you couldnt just easily pull it up and then click it in, you had to first pulll it far out kinda hold it from going back in, click, then let it tighten because if youre wearing clothes like jeans or a coat etc and the large distance over the side of seat and your body and a sharp 90 degrees it had to wipe across meant it would just retract and they were never lubed or cleaned so i bet they were harder to pull even then lol.

I havent had to face that problem since before hte seatbelt was larger than my arm tho.. so maybe i was just weak child LOL
 

AuroraGirl

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May also give younger Police Officers probable cause. They can't see the belts on and don't know our older trucks are not equipped with shoulder belts??!!!
Probable cause would be found valid in court, however, you havent committed a crime if pulled over when you are wearing it. not even the harshest state on safety has rules requiring retrofit of shoulder 3 points to lap belts.
 

AuroraGirl

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there I spun the photo around so it was easier to understand what is going on in the pic, this is the driver side of truck, with a bucket seat, so the belt is close to center in the cab but its just laying down. Presumably it would stake in the plastic pocket thing or perhaps stays up right next to the seat if you lean it forward and the seat is back, but presumably it goes to the floor if you push it there, so its out of way when laws were lax/you didnt care
 

Raybo135

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1976
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K10 Silverado
Engine Size
400
My 1975 GMC 3/4 ton is like that too. Believe it or not, the vehicle's GVW is determines what you get for seat belts. In vehicles that are (if I remember right) 8600GVW and up, you just got lap belts as standard equipment. Three point belts were optional. Lower GVW trucks all got the three point seatbelts, as well as a seatbelt light and buzzer as standard equipment a few years before they showed up on 3/4 ton-up trucks.
My original 1976 I bought in 1975 only had a lab belt, and it was a K-10 Custom Deluxe with 6200GVW. But it did have the bolt holes for a shoulder belt to bolt into the pillar. In 1976, the GVW 6200 was considered Heavy Duty. However, I have a newer 1976 now and it does have the same GVW rating, but it is a Silverado, and it has the Lap/Shoulder combination.
 

Ellie Niner

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K10 Silverado
Engine Size
LE9 305
May also give younger Police Officers probable cause. They can't see the belts on and don't know our older trucks are not equipped with shoulder belts??!!!
I've been there in my '75. Actually happened back around 2005-07, and I was pulled over for something random and stupid late at night- which was pretty common practice in the small-ish town I lived in if you were driving around when the bars closed... the porkies operated under the general assumption that if you were on the road at 2:15am, you had been drinking (I actually worked nights, so was... on the road?). After sniffing around, checking my insurance and registration, and finding nothing wrong, he told me he was going to write me a ticket for no seatbelt. I showed him the buckled lap belt around my waist; he balked, and acted confused as I showed him the plugs in the door pillar where shoulder harnesses would go if they'd been ordered. After grilling me a bit more and asking if I had removed three point seatbelts from the truck and installed the plugs (the plugs were painted the same metallic green as the inside of the cab), he finally backed down and let me go.

Also had another similar incident where a cop got bent after looking for my truck's VIN at the base of the windshield, and not finding it. Same attitude as the other... he first accused me of making illegal modifications to my vehicle before taking my word that the tag he was looking for was inside the door pillar. He then made me get out of the vehicle (presumably so I couldn't bean him in the head while he was inspecting the data plate) and stand at the back with my hands on the tailgate. This happened in a busy area of the same small town, so of course people I knew and somebody from my work saw me there and questioned me about it later. And same as the first one, he eventually let me go... without apologizing for pissing in my Wheaties for no good reason.

@Raybo135 Thanks for the info. It's been a long time since I studied those particular regulations, so my memory is a bit fuzzy... it was probably right after that cop flipped me so much sh¡t about only having lap belts.
 

WFO

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K20
Engine Size
350
I don't know about other States, but in Texas you don't have to wear shoulder or lap belts on a vehicle that didn't come with shoulder belts as standard equipment. Lap belts alone are unsafe.
Like my 69 Chevelle SS, which has optional shoulder belts that are folded up and placed in clips above the door windows. Since they were an option item, I don't need to wear any belts.
If I sense that a wreck is going to be real bad, I like having the option of diving to the floorboard.
 

Snoots

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Jimmy Sierra
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I've twice been stopped (in my '73) and opened the door so the officer could see that I was wearing a seat belt. When they asked why I opened the door they asked about it and I told them why. No ticket. EOS.
 

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