1972 LT1 Roadster with AV3 option.

[J I.]

Dear Fellow NCRS members,

My 72 LT1 convertible is marked from GM as having RPO code AV3 described by GM as "Three Point Seat & Shoulder Harness". Indeed, the car has its original lap belts as well as the steel threaded brace in the wheel well to reinstall the car's missing original shoulder belts. I have found a proper set of date code correct OEM shoulder belts. The question I have is, "why is the 1972 option list saying that shoulder belts for roadsters was code A85, as shoulder belts AV3 were standard for coupes only". Thank you! Darren

19467 Built Feb 28, 1972

Trim 400
Paint 76
Top A
AV3
A31
C05
GS4
J50
LT1
L08
N40
PU9
U69
ZK8
ZW4
Z49
W84

[Harmon C.]

Re: 1972 LT1 Roadster with AV3 option.

Without the A85 code I would say your 72 did not have shoulder belts from the factory. All cars had the threaded holes in the body.

[J I.]

Re: 1972 LT1 Roadster with AV3 option.

[QUOTE=Lyle Chamberlain (24961);751107]Without the A85 code I would say your 72 did not have shoulder belts from the factory. All cars had the threaded holes in the body.[/QUOTE

Well, therein lies the mystery Lyle. The code says a "3 point seat and shoulder harness". If it just had the seat belts, that would be a 2 point belt system. The car has the correct interior rear vinyl with the seat belt provisions as do the seats. So the mystery is compounded by having most of the shoulder belt attributes. I have had a 100 plus views and to date, only one response. So the plot thickens! Thank you kindly for your message Lyle. Best Wishes, Darren

[Robert R.]

Re: 1972 LT1 Roadster with AV3 option.

Since the shoulder belt goes through the seat back, do your seats have the holes on the outer portion of the backs?
Non shoulder belt convertibles do not have the holes on either side.

[Edward J.]

Re: 1972 LT1 Roadster with AV3 option.

Darren, in 72 I believe the couple the shoulder harness was standard and Conv. it was a option. I cannot tell you why.

[Michael W.]

Re: 1972 LT1 Roadster with AV3 option.

To add to the mystery:

RPO AV3 seems to only appear in the 1972 model year statistics and no other.

In that production year, 20,496 coupes were built. Only 13,668 are listed as having AV3, despite three point belts being standard. Normally, 'standard equipment' would not have an RPO code attached and listed.

Similarly, 6,508 convertibles were built in '72 but supposedly 4,025 had AV3.

The optional deluxe shoulder harness RPO AB5 (or A85) was fitted to 749 convertibles.

None of these numbers add up.

Thinking that RPO AV3 was something other than seatbelts, a search shows that on other GM vehicles, this code refers to a cargo net tie down system or an electric sunroof. GM is known to have reused RPO codes over the years for entirely different options.

I found this post of relevance on a Chevelle site

http://www.chevelles.com/forums/showthread.php?t=628145

where there is some discussion of the AV3 code being more to do with the seat belt warning system rather than the belts themselves. Was there a running change to the seatbelt warning system in 1972?

[Leonard M.]

Re: 1972 LT1 Roadster with AV3 option.

I agree with Mike that AV3 is not any sort of optional seat belt. I have a low mileage, very original 1972 roadster with standard lap belts, seat belt warning light/buzzer. I removed the tank sticker and even though the hole is after AV3 I don't think there was anything typed in. Mystery yes, option no.
tank sticker.jpg

[Reba W.]

Re: 1972 LT1 Roadster with AV3 option.

To add to the mystery:

There is some discussion of the AV3 code being more to do with the seat belt warning system rather than the belts themselves. Was there a running change to the seatbelt warning system in 1972?

Yes there was a change. Up until about mid-December 1971, 1972s had a seatbelt warning light on the dash that timed out. After that, there was a buzzer that sounded until the belt(s) was buckled.

[Harmon C.]

Re: 1972 LT1 Roadster with AV3 option.

I have never seen original rear trim without the cut outs for shoulder belts in a convertible. If the metal trim in the seat back has the hole for the seat belt to go through and the metal trim in back I would say the Corvette came from the factory with shoulder belts. Shoulder belts did not not rust like the lap belts so their would be no reason to remove them.

[Michael W.]

Re: 1972 LT1 Roadster with AV3 option.

Yes there was a change. Up until about mid-December 1971, 1972s had a seatbelt warning light on the dash that timed out. After that, there was a buzzer that sounded until the belt(s) was buckled.

This might be the answer then.

The total number of cars built with AV03 according to GM stats was 17,693, meaning that this feature would have been introduced on car 09311. That car was assembled around Dec 14 1971.

It appears that AV03 denotes the existence of a seat belt buzzer.