Steering Box Help

[Bryan L.]

I ran across four Saginaw steering boxes yesterday but I'm having problems deciphering the numbers on them. Can anyone help me out ?

Box #1 Number on the body is 5677648 Cover 7802287 There's also "CBC" below the number

Box #2 Number on the body is 5677648 Cover 66723 62

Box #3 Number on the body is 5677649 Cover 7802287 and a small metal tag attached to one of the cover bolts 065-6
on this box there's also two diamonds with a 2 to the right.

Box #4 Number on the body is 5677649 Cover 7802287 and a small metal tag attached to one of the cover bolts 279-6
on this box there's also two diamonds with a 3 to the right.

I appreciate the help and if anyone knows of a book that will provide this information, I'd like to get it.

Thanks again

[Joe L.]

Re: Steering Box Help

I ran across four Saginaw steering boxes yesterday but I'm having problems deciphering the numbers on them. Can anyone help me out ?

Box #1 Number on the body is 5677648 Cover 7802287 There's also "CBC" below the number

Box #2 Number on the body is 5677648 Cover 66723 62

Box #3 Number on the body is 5677649 Cover 7802287 and a small metal tag attached to one of the cover bolts 065-6
on this box there's also two diamonds with a 2 to the right.

Box #4 Number on the body is 5677649 Cover 7802287 and a small metal tag attached to one of the cover bolts 279-6
on this box there's also two diamonds with a 3 to the right.

I appreciate the help and if anyone knows of a book that will provide this information, I'd like to get it.

Thanks again

Bryan------


I think you'll find that all of the steering box housings are casting number 5677649. Certain digits are easily confused with casting numbers. In any event, all original 1963-82 Corvettes used the same casting number for the steering box housing.

Without getting into nuances, it's like this:

1963-68 Corvette steering boxes use a cast iron cover. There were a few minor variations over the years. Some of these have the number "6723" cast into them. These boxes have a full round, splined input shaft;

1969-82 Corvette steering boxes use an aluminum cover. Some of these have the 7802287 casting number and some have no GM casting number but have other various numbers. I don't know what they denote. Early 1969 steering boxes use the full round, splined input shaft the same as earlier. Very late 1969-82 Corvettes use an input shaft with a flat on it.

What the metal tags denote I do not know. However, I've only seen these on later C3 steering boxes.

[Gary R.]

Re: Steering Box Help

Starting about 74, certainly by 75 there is a date code cast in the back of the box in line the Road S. There is a metal tag attached to one of the cover bolts with the assembly date cover stamped on it. This started with the casting dates in 74-75.

The earlier casting also had a "A" in a circle on the back and the early 70's had a "T"- I don't know what this signifies, then the date coding started.

As Joe mentioned the 63-68 boxes has iron covers, the 63 was thinner and only had a casting number in it, the 64-68 had Add Lube cast around the center cover bolt. They used hex bolts and lock washers. The aluminum cover bolts were self locking flange heads.

The lower seals on the 63-68 where single lip, the 69-82 and the service parts use a black double lip seal.

About 77-78 the cover bushings were replaced by a thin cupped bushing, not sure why this happened either. Production cost? The castings also changed around the two vertical bolt holes, there was more casting around the upper one.

The ratios were all the same from 63-82 except for the 5 original Gran Sports which had faster ratios.

While numbers are important I would be more concerned with the condition of the boxes and gears. Look at the lash screw, if there are a couple of threads and the box is snug the gears may still be good. If there are no threads showing and the feel is loose then the gears are probably shot. If the box sat for a long time corrosion could be a problem.