Steering Box Cores

[Gary R.]

Today was a nice day in CT, 90* when Monday it was 40*!

Since I had the day off I took a nice 2 hour ride to meet a fellow corvette hobbyist and pick up some steering box cores to build in my spare time. These are all cores, needing new gear sets. I have plenty of new gears left.

There was recently a question on box differences, basically covers used over the years. I found an interesting box in the group and figured I would share with you.

I quickly marked them when I got home in yellow paint but I think the one I marked 69-74 is a 69 late box with D-Flat. These are all 649 boxes. I know there are supposed to be other casting numbers but the ones I see are all 649's. The later boxes had the number in lower back of the box, the earlier boxes on the upper backside. The date coding I think started in '75, there is a casting date on the back and the cover tag has the assembly day and year. The earlier boxes didn't have this feature.

The boxes around 65-68 had an "A" in a circle on the back, the 70-72 maybe 73's had a "T" in a circle. I don't know the significance of this, maybe someone out there does?

The 75 casting is the oddball. All 75 boxes I have built, a that's a lot, had the early casting. The 78-82's had the casting shown for this 75 but it clearly is dated 1975? I never saw that before.

The unpainted box I marked as 64-68 is not a 64-68 but rather a 64-66

Anyway it was a nice day for a country ride.

[Gary R.]

Re: Steering Box Cores

63 Grand Sport box





Drilled for safety wiring the cover bolts

[Mark P.]

Re: Steering Box Cores

You scored a lot of boxes. Good to have them to keep our cars on the road.

Do you think the Grand Sport box was used on any other cars Gary ? Hard to imagine one of those being found. Is it made out of Aluminum to save weight ?

Does the 55 on my cover tell you the date ? If so, what date is it ? My car was assembled 2/4/65.

[Gary R.]

Re: Steering Box Cores

Hi Mark,
I believe the GS boxes were limited to the GS, since I was about 3 years ago at the time I wasn't able to check with my local dealer to see if they could get them-LOL. I suspect there were more then 5 built but I really can't say for sure. They used the same bushings and bearings but had a faster 12:1 ratio gear. I don't know if the gear was ever a service part, again I doubt it.

I am not sure if the 2 digit number on the cover is a date code. I see different numbers there and there were 3 variations of the iron covers.
1- 1963 - everyone I worked on did not have "ADD LUBE" cast into them, just a casting number
2- 64-66 iron covers with radius this looks like the 63 cover only with "add Lube" in it

Your box cover is what I call a square cover.
3-67-68 sq cover - What I call the sq cover- they are squared off where the others are full radius

I have found both radius and sq covers on original boxes through the 64-66 range.

[Joe L.]

Re: Steering Box Cores

Hi Mark,
I believe the GS boxes were limited to the GS, since I was about 3 years ago at the time I wasn't able to check with my local dealer to see if they could get them-LOL. I suspect there were more then 5 built but I really can't say for sure. They used the same bushings and bearings but had a faster 12:1 ratio gear. I don't know if the gear was ever a service part, again I doubt it.

I am not sure if the 2 digit number on the cover is a date code. I see different numbers there and there were 3 variations of the iron covers.
1- 1963 - everyone I worked on did not have "ADD LUBE" cast into them, just a casting number
2- 64-66 iron covers with radius this looks like the 63 cover only with "add Lube" in it

Your box cover is what I call a square cover.
3-67-68 sq cover - What I call the sq cover- they are squared off where the others are full radius

I have found both radius and sq covers on original boxes through the 64-66 range.

Gary------

Note the "special-series" part number on the GS steering box cover. That would indicate an "experimental" or "one-off" type part. It's possible that the complete assembly had a regular part number but I highly doubt it was ever a SERVICE-available part.

I've seen the "55" on Mark's cover before. I don't know what it denotes but I'm virtually certain it has nothing to do with a date. Also note the small symbol on the other side of the cover. This looks to me like it might be a non-GM foundry mark. If so, it would indicate that, at some point, GM outsourced the casting of these covers.