1981 Spare Tire: Date Code on Wheel?

[Brad H.]

I am inspecting my spare tire and wheel for June St. Louis built 1981. The steel rim has a stamping by the valve stem and also by the center hub of K31. Page 58 of the 1980-2 TIMJG states that the stamped code should be K37, K38 or K39 with: K=Kelsey Hayes, 3=manufacturing plant, and 7,8,9 = the last digit of the calendar year.

My question is: Would the plant have been installing spare tire/wheel dated from 1977 through 1979 in 1981 Corvettes? That seems like a very long lead time. By decoding K31, does 1=1981 and would that be more correct for a 1981 to have as a spare than one dated for 1977-79?

The spare is a "temporary use only" Goodyear "Polyspare" 195/80D15 and appears to be original to the car and has appears to not have been dismounted from the wheel. I let a little bit of air out of the valve stem and it definitely smelled like St. Louis air.

Thanks for any advice on if the spare and rim are date coded correctly for the car even though it does not match the TIMJG.

Brad Hillhouse
37766

[David H.]

Re: 1981 Spare Tire: Date Code on Wheel?

I am inspecting my spare tire and wheel for June St. Louis built 1981. The steel rim has a stamping by the valve stem and also by the center hub of K31. Page 58 of the 1980-2 TIMJG states that the stamped code should be K37, K38 or K39 with: K=Kelsey Hayes, 3=manufacturing plant, and 7,8,9 = the last digit of the calendar year.

My question is: Would the plant have been installing spare tire/wheel dated from 1977 through 1979 in 1981 Corvettes? That seems like a very long lead time. By decoding K31, does 1=1981 and would that be more correct for a 1981 to have as a spare than one dated for 1977-79?

The spare is a "temporary use only" Goodyear "Polyspare" 195/80D15 and appears to be original to the car and has appears to not have been dismounted from the wheel. I let a little bit of air out of the valve stem and it definitely smelled like St. Louis air.

Thanks for any advice on if the spare and rim are date coded correctly for the car even though it does not match the TIMJG.

Brad Hillhouse
37766

Brad,

The spare tire wheel on my 1980 reads "K30". "K" for Kelsey Hayes, 3 for Mfg Plant, and last digit year for 1980. I don't have the 1978-1979 Judging Guide at hand, but, I'll bet you a three day-old donut - verbiage found in 1980-1982 JG was extracted from an earlier JG and never changed.

Upshot is your "K31" is OK.

Just curious, what are the other stamps? "YA" for size code. But for Date? Mine just says "17" along rim.

Hub has "K30", "A", and "4" stamps.

Dave

[Brad Hillhouse (37766)]

Re: 1981 Spare Tire: Date Code on Wheel?

Dave - At the valve stem I have the "K31" stamped on one side of the hole and a YA in larger letters and "27".

At the hub center: Between one bolt hole is "K31", the next hole has "A", the next hole "27".

As a smart one once told me, Dont change your car to match the judging manual! I am following that advice, and appreciate your explanation that the 80-82 TIMJG may have used wording from the 78-9 manual.

The Tire code stamped into the sidewall appears to be "301R". I am still struggling to decode tire dates, if you could be of any help on that matter, I would appreciate that as well. It has the last 2 digits of the VIN written on the tire in yellow grease pencil. I have found those 2 numbers on several other places hand written on the car also. This leads me to believe that it is the one that was born with the car.

Thanks for responding Dave!

Brad Hillhouse
37766

[Ronald L.]

Re: 1981 Spare Tire: Date Code on Wheel?

What year were these painted yellow?

[Tom R.]

Re: 1981 Spare Tire: Date Code on Wheel?

What year were these painted yellow?

The rims were yellow in 1978 and ended about the time when Pace Cars were rolling on the streets. I surveyed Pace Cars with yellow rims and tell the story that about the time executives were sporting around town but got a flat and then rode the town with yellow rims, was about the time Corvette ordered the change from yellow to black rims. Attached find link to the story and some graphics.

http://www.hunt4cleanair.net/Articles/YellowSpare.pdf

[Ronald L.]

Re: 1981 Spare Tire: Date Code on Wheel?

Tom
Wow - you did all the work on this one, thank you for posting your article.

[Tom R.]

Re: 1981 Spare Tire: Date Code on Wheel?

Yeah...four pages to describe a yellow rim and suspend the myth that yellow rims were limited to early 1978s.

[Harris B.]

Re: 1981 Spare Tire: Date Code on Wheel?

Here are some pictures of the spare tire before and after I washed it on my '81 Bowling Green VIN 219 early built June 1981. Pictures in no particular order spare2.jpgspare1.jpgspare3.jpgspare4.jpgspare5.jpgspare6.jpgspare7.jpg

[Tom R.]

Re: 1981 Spare Tire: Date Code on Wheel?

You missed a closeup of the tire date code...what's embossed under the DOT.