F15a steering knuckles

[Dave Schindel]

OK , beginning to look like the 1/2 in. threaded one goes on the right and 7/16 on the left. I have a 1/2 in. threaded one that came off the right side. I have 2 others I have not checked yet. I did not realize there was a difference in threads.

[Jacques Reed]

Further to the part numbers previously listed:

The first digit after the "C" in the part number is the year the part was designed and released.

Therefore the knuckles starting with C1 were designed and released in 1941 and the one with the number starting with C0 were designed and released in 1940.

Points to early pre 1941 CMP F15A's had the two size studs on the knuckles and later they standardized them to the larger 1/2" diameter studs.

Both sides of my 1944 model have 1/2" diameter studs.

No doubt there would be exceptions due to using up old stock post 1941 and replacement parts.

I bought the early 7/16" stud NOS knuckle for a spare a while back and only realized the difference when I brought it home. Thought maybe it was for a Marmon Herrington afterwards so on the shelf it sits. Anyone want it?

Cheers,

[Jacques Reed]

Now I am confused (More so than normal!)

While putting away the knuckles I photographed for the earlier post I noticed the Part number C01Q 3358 cast into one of the knuckles as per the photo attached. None of the other two knuckles had any numbers cast into them.

Very different to the F15A parts list numbers I quoted.

It definitely came off a 4-7/8" steering end as used on the F15A. Still, as is often the case, it does not mean it is the correct one.

I don't have a parts list for the larger trucks with 6" steering ends and would have thought those knuckles would not be the same size but could it be?

Anyone able to shed some light on this one?

[Dave Schindel]

Tough one.....none of my knuckles have numbers,at least none that I could find.Just the Ford logo stamped on the inside near the bearing race.

[Dave Schindel]

Rob, I am guessing that the 1/2 in. studs were used where the steering arm attaches to the knuckle and the others were 7/16. Later they were all tapped to 1/2?

[rob love]

It would make sense, in the interest of carrying less spare parts in the supply system, to make the left and right the same. So to that end, you would have to go with 1/2 inch, since that was required to handle the load of turning 2 wheels. The left side only had to handle the load of turning one, so in that case 7/16 studs would have sufficed engineering wise.

Checked a 44 Chev 15cwt Sigs van that is apart and sitting about 30' from me. Sure enough, 1/2" threaded holes on the left side and the C01Q-3348 part number on the casting.

[Jacques Reed]

Hi Rob,

After reading about your part C01Q-3348 on A Chev CMP and my C01Q-3358 off a Ford CMP perhaps Ford assigned different numbers to parts earmarked for Chev truck production? Can anyone shed any light on that as I don't have any Chev Parts manual to check.

Have looked in my GM MB-C1 Maintenances Manual but no reference there to part numbers in the front axle section. GM seems to avoid part number in their Maintenance Manual whereas Ford seems to often quote them.

Cheers,