With the post on the rear axle ratio, I used a calculator that was posted and the RPM didnt match up with my specs at 40 mph indicated. I feel the speedometer has to be right because from the driveway at work to the stoplight on the way home is 1.10 miles. My trip odometer was almost at 1.1 miles when I stopped at the light.

But I wanted to ask this question on the driven gears, if I were to change it out what would be the difference in mph between a 14 tooth and a 16 tooth driven gear?

With the 31x10.50-15 tires I am running over stock and the stock 2.75:1 axle ratio TCI`s calculator indicates I need a 14.29 tooth driven gear with a 8 tooth drive gear. The Ford Parts & Illustration manual indicates a 8 tooth drive gear for 81 to 86 F100-250 trucks.

I will be finding and installing a GPS speedometer for my phone and will verify the speed tomorrow at lunch, but if the 16 tooth driven gear is closer than what I have currently indicated if it truely is off I will go with that.

 

Where in the parts catalog did you come up with this dubious info? It's not listed in the speedo gear charts, because...

C6 = The speedometer DRIVE gear is made as part of the output shaft, so it cannot be replaced by itself.

The only way to find out how many teeth on the DRIVE gear is by looking up the output shaft.

1982 F150 302/C6 2WD: There are three different output shafts listed. One has a 6T DRIVE gear, another has a 7T, and yet another has an 8T.

FoMoCo has never offered a 14T DRIVEN gear, only 16 thru 21T.

17271 = DRIVEN gear, pic at right lists number of teeth.

 

Dubious info? What happened to the wild mule ****, Bill?

 

Where is it? Here

Section A70.4 page 3

Part # 7060 Output Shaft

part # E1TZ 7060-A 1981 - 1982 Before 10/19/81 - 16" Length / 8-Tooth Speedo Gear

Part # E8AT 7060-A 1982 - 1986 From 10/19/81 - 15" Length / 8-Tooth Speedo Gear

Not from the page I listed above, the 7-tooth drive gear for a C6 is listed as being 1983 and newer. For a 1982 year model truck there is two different shafts listed and the only difference is one is a inch shorter than the other but the number of teeth on the drive gear is the same.



I also never said Ford made a 14 Tooth driven gear, I said I need a 14 Tooth but 16 is the closest I can get, which is the whole basis of this post is how much of a difference speed wise would two teeth more make. I know the speedometer will read slower than it would with a 14 Tooth using the 16 Tooth but I am curious how much slower. I will be verifying my speedometer on the way back to work after lunch with a GPS Speedometer app I downloaded.

Yes I see now though that there are three different Tooth drive gears for those years, but for my year there is only one, not three as was stated.

 

A70.3 = Three possible 1982 F150 302/C6 2WD output shafts, one has a 6T DRIVE gear, another has 7T, and yet another has 8T.

Doncha think that after looking this crap up for 42 + years, I would know the difference between a C6 & AOT?

 

Rusty - Section A70.x is for automatic transmissions... the .x refers to each specific variant.

 

I typed wild mule p!ss originally, then changed it to dubious.

A70.3 = C6 / A70.4 = AOT (AOD).

Post 4: OP looked up the wrong (A70.4 ~ AOT) output shafts.

 

Ok, thats fine, I never heard of the AOD being refered to as a AOT. Sure I will admit that I looked at the wrong section. But and this is where I have a issue with the replies I am getting. There is no need to get upset and then start **** up. I did not seek your help for part numbers, nor have you answered my question. You responded to this post and proceeded to attack something I said, this could have been handled nicely if you wouldnt have came in with a chip on your shoulder acting like your my holy savior to save the day for me when in fact, you derailed this whole topic and never once answered the question that this topic was asking.

I also have to be blunt and say I dont care how long youve been looking up ford parts, I used to have quite a bit of respect towards you that has now been lost because of how youve acted towards me when I havent done a thing to you.

Yes I know that now. I went to the same section that was for the C6 in the illustration guide. Must have been different cause I saw AOT but didnt know what that was about or stood for considering ive never heard of an AOD being called a AOT, I even asked my co workers at work who have been in the repair field since the 70`s and they never heard of an AOD being refered to as an AOT.

Something new for me and it is now known.

Yes I was wrong, but this is the thing that has me furious over. You came in here basically to beat your chest and point out how wrong I was and derailed my topic to the point that no one has posted to answer my question because the topic has been so derailed by you that people think I am asking about the drive gear when I asked about the driven gear, so there's zero hope now of getting my question answered. But that doesn't matter anymore as I verified that my actual speed and indicated speed is only 1 to 2 mph off which is not as bad as I believed, so this topic can be locked as I will not be posting on this topic any more.

 

Bill is big on accuracy and correct information being published on forums such as this one; not only for the OP but for those who come across this thread in a Google search in the future while trying to research their own problems.

 

Thats fine, I can understand that. But theres no need to put it in the tone that it was. There was also no need to hijack my post and burry my question and turn it into a debate on something that wasnt even in question by me.

 

Yes, the emoticons he sometimes uses shaking one's head, etc. make a condescending impression, I wish he wouldn't do that.

But if you ever get to talk to him on the phone - or meet him in real life - you might better understand his demeanor and just say to yourself, "Yeah, that's Bill" when he comes across that way which he does to me, too, I'm not immune to it but I've just learned to look at it in a different light, kinda like a different tone of voice.

Take the good with the bad with everybody, I suppose...

 

I believe the "AOT" was Ford's internal designation for the trans, and stood for "Automatic Overdrive Transmission". The AOD moniker was added by the rest of the industry, since it's rather obvious it's a transmission....

Bill's wife (or as he calls her "She who must be obeyed") just retired. I'd prolly be a bit grumpy too, if I had a woman nagging me all day.
I wish I could say that this was the reason he comes across grumpy, but he's been that way a long time........

I respect his knowledge, and the (usually) valuable info he provides. I do not like the manner in which he does it, sometimes. Still, overall, this site is better with him around, than it would be were he not.

He can be a grumpy old cuss sometimes, but then again, so can I.

 

I posted the parts catalog page that shows the available DRIVEN gears with 2.75-1/C6, so you can figure out for yourself which one will work.

You didn't ask for my help, but how many other members could answer your question? One needs the parts catalog, and only a few members have it.

I've been a grumpy crab for decades. When one waits on people at parts counters for 35 years, plus another 7+ years on FTE, one finds out PDQ that dealing with the public ain't easy.

And btw, Chris knows me personally, as he's been my house guest twice. 17 days in April 2013, another 9 days in April 2014.

During his last stay when we went shopping for a new computer (my laptop died just after he got here), he said...you can be harder to get along with in person than you are on FTE.

My answer was...that I like things just so, and if things occur that muddy the waters, I'm going to b!tch about it.

 

When the AOD first came out it was referred to as an FIOD.


Just to throw some stuff around.

 

Using the Search function of a PDF reader to locate a part number is one way to end up with the wrong information. Just sayin....