Speedo cable driven gear color code

[BigBrother-84]

Hi Gentlemen!

I want to replace the speedo driven gear and I'm a bit confused about what to order...

Here is Big Bro's one, gray, 18 tooth:

Table shows that "gray" gear is part C7SZ-17271-B:

But googling this number gives me anything but the gray.

Well, almost, since I get one "gray" result on eBay, 75$ US plus shipping!!

Amazon shows a "gray" result, 25$ CAD shipping included, but with a different number (C7SZ-17271-C):

.

[85pig]

Count the number of teeth (Ford typically put it on the flat top of the gear "17T", "19T", etc.), and note which direction the teeth go - left or right (yours appear to be right in the photo), and order that gear from an online source. I think the aftermarket gears are fine. Ford also made a longer driven gear, as well as longer and shorter snouts, just order the one that resembles what you have, and you should be good to go.

[Gary Lewis]

I think the Amazon one is what you want. Amazon is listing the Identification # not the Part #. The Part # you want is C7SV-B but according to the 2nd chart the ID # is C7SV-C, which is what Amazon shows.

Don't ask me why the upper chart shows a different ID #. Maybe Ralph knows?

[81-F150-Explorer]

I think the Amazon one is what you want. Amazon is listing the Identification # not the Part #. The Part # you want is C7SV-B but according to the 2nd chart the ID # is C7SV-C, which is what Amazon shows.

Don't ask me why the upper chart shows a different ID #. Maybe Ralph knows?

C7SZ-17271-B was replaced by C7SZ-17271-C

Info Thanks to Bill AKA: Numberdummy.

[Gary Lewis]

C7SZ-17271-B was replaced by C7SZ-17271-C

Info Thanks to Bill AKA: Numberdummy.

Thanks, Ralph!

[BigBrother-84]

Thanks, Ralph!

Thanks Gentlemen!

The Amazon one looks pretty identical to Big Bro’s. Which is a bit worn, not so much, 18T, same angle direction:

Now, about the speedo drive gear… In your experience, is it stronger than the driven gear, so this latter will worn before the drive gear does?

Or, too bad man, you have to replace the two gears?

If so, can we trust the table, so Big Bro’s speedo drive gear should be white, part #E3TZ-17285-C:

 

[Gary Lewis]

Thanks Gentlemen!

The Amazon one looks pretty identical to Big Bro’s. Which is a bit worn, not so much, 18T, same angle direction:

Now, about the speedo drive gear… In your experience, is it stronger than the driven gear, so this latter will worn before the drive gear does?

Or, too bad man, you have to replace the two gears?

If so, can we trust the table, so Big Bro’s speedo drive gear should be white, part #E3TZ-17285-C:

In my experience the drive gear seems to wear less than the driven gear.

[BigBrother-84]

In my experience the drive gear seems to wear less than the driven gear.

That would be logical that the easiest part to reach and replace is the more "fragile" one...

But sometimes mechanic is fascinating but not logical.

I'll see if replacing only the driven gear fixes my "jumping" needle.

[BigBrother-84]

That would be logical that the easiest part to reach and replace is the more "fragile" one...

But sometimes mechanic is fascinating but not logical.

I'll see if replacing only the driven gear fixes my "jumping" needle.

Or, should I say 🖖

[Gary Lewis]

That would be logical that the easiest part to reach and replace is the more "fragile" one...

But sometimes mechanic is fascinating but not logical.

I'll see if replacing only the driven gear fixes my "jumping" needle.

If the gear doesn't look bad then I'd lube the speedo cable. Yours is loooooong and can easily wrap & unwrap in that length if dry, and that'll cause all sorts of twitchyness on the speedo. I had fits with this on Big Blue, and what I finally did that solved the problem was to run Mobil 1 wheel bearing grease in the cable. That tamed, but didn't completely eliminate, the twitchyness.

I think we may have had this "conversation" before, and if so please forgive my forgetfulness.