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Last week I bought a '66 F-100 from a local guy. Red lower/White upper, 351W with electric fuel pump, automatic with shifter moved to the floor, etc. Patch panel on the pass side, only a couple of pinholes in the driver's side floor pan. Overall not a bad looking truck. $1200 and I drove it home. I had been looking for an old truck, so I'm pleased with it so far. Couple of questions though....

1) Brake lights (or lack thereof). The tail lights work, but do not brighten when the brakes are applied, nor do they blink to give a turn signal. The turn signal blinkers also do not work on the front upper lights, although the lights do light up when the parking lights are on. I'm trying to figure out the brake light problem first, although I guess it could be related to the blinker issue. I noticed it has a sending unit that screws into the master cyclinder, whereas my '65 Mustang has a sensor thing that the brake pedal itself comes into contact with. One of the wires going to the sending unit has 12V or so when the vehicle is running, the other has no power. There is not a low brake pressure light hooked up as far as I can tell. I have followed the two wires into the cab and they disappear into the main harness. All fuses are good (I learned a long time ago to check the easy stuff first LOL), and I replaced the sending unit as a precaution but that did not help, still no brake lights. So today I drove half an hour to Chattanooga TN to buy a book (Chiltons, covers '65 to 80-something) but it is pretty useless when it comes to wiring of the lights. What do you guys recommend for a starting point on fixing this thing? I plan to order a shop manual, but I'd like to get some work done tomorrow if possible. I'm dying to drive it to work but I can't without brake lights. I even climbed under the truck to follow the wires to the back and found no bad spots in the wiring.

2) The truck needs a new ignition cylinder (the one in it now is aftermarket, and sticks a little so it's hard to start the truck), and the previous owner didn't have the keys to the doors. I want to get a new cylinder and door lock cylinders all keyed the same. Any idea if the Mustang ignition cylinder and door lock cylinders are interchangeable with the F-100s?

3) What kind of tranny is this? The pan is not a rectangle like my C-4 and AOD. It is shaped like a rectangle with one corner missing, if that makes sense. The vacuum modulator is on the back, when the "missing corner" is. One tranny cooler line goes to the front near the bellhousing, and the other goes toward the back, both on the passenger side. It says Ford on the tranny casing so I know it isn't a GM conversion (sadly, I know of people that are doing that kind of thing and bastardizing a perfectly good vehicle...). It's a 3 speed automatic, so I figure it has to be either C-4, C-5 (?), C-6, or FMX. Any ideas?

Thanks for the help guys /forums/images/icons/smile.gif

Shane
 

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3.-I used to have a tranny ID chart somewhere that ID's them by the pans. Can't find it. Anyway, an FMX is unique and easy to spot from underneath. The center section is a cast iron case while the bellhousing and tailshaft sections are cast aluminun. A C6 looks like a big C4 but is one solid chunk of aluminum-front to back.
1. Brake lights and turn signals are tied in together. For example-When you at a stop sign wanting to turn left you only have one brake light-the right one. The left one is a blinking turn signal, like the left front signal light. Yet if you are not making a turn, you'll have two brake lights. This bit of electrical juggling is a SOB to work on sometimes. You did check the bulbs didn't you? The bulbs have two filaments (GE #1157) so you could have working taillights and still have bad bulbs. I hope it's that easy but I suspect the turn signal switch. Good luck!
 

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I checked each of the tail light and front turn signal indicator/parking light bulbs and replaced them with new 1157KR (supposed to last 2X as long as regular 1157 according to the package) just to be sure. I also checked the voltage at the sockets...left side (IIRC) 12V when the driving or parking lights were on, 0 when off, and the right side (IIRC) 0 volts regardless of headlight switch position or turn signal arm position or brake pedal position. The truck has a small aftermarket steering wheel, and for that matter I'm not sure it's the original steering column, so something could be going on under there I guess. The reason I suspect it isn't the original steering column is because it has a hole on the side for an ignition cylinder, but the original ign cylinder (as best I can tell...) is on the left-hand side of the dash. Is there an easy way to bypass the turnsignal switch for troubleshooting purposes? I'll take a closer look tomorrow to see where the turn signal wiring exits the steering column (if it does at all....). Thanks! /forums/images/icons/smile.gif
 
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Congrats on the truck. We just got a slick but not running '65 for the wife... another big block project. The ignition switcho on the truck & Mustang are the same as I believe the doors are as well. The electrical system is best left to a test light, those books are crap. Last one I did a conversion on I used the brake pedal from a later truck & ran the wires inside the cab using a conventional switch. If you need some guidance on your project holler... I get bored & try to help. If you want any kind of parts, I'm trying to get a '66 parts truck & I know all the places to get all the good stuff( like drop I-Beams) & what works & what doesn't.
 

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Congrats on what sounds like a cool truck....I'd bet that there are lots of parts that are interchangeable with other Fords of the same year. From my experience, Ford seemed to have used as many of the same parts. For example, I saw a '66 Fairlane GT at a show last year, and actually saw about 10 identical trim parts with GT mustangs. I'm sure there were many more same mechanical parts that I could not see....Dickson
 

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Only help I can be is, transmission sounds like a C6 to me.
 

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I can't think of an easy bypass for your problem. If you could find a wiring diagram somewhere that'd help a lot. Sounds like PrairieBronze may be a big help since he has one too.
Somebody posted a while back about a F100 forum somewhere, might be worth looking into.
The only "easy" way to resurrect very dead turnsignals is to purchase a "7 wire turnsignal kit". I believe NAPA still sells them. It's a completely independent turnsignal setup. A gawky looking self-contained switch that clamps onto any steering column. Not a pretty solution, but if you get desperate for a temporary fix.... Hopefully the instructions cover brake lights too.
A company I used to work for had a small fleet of older work trucks and an overworked maintenance mechanic. He was a big fan of these kits. If your turn signals stopped working for any reason, you'd have one of these kits on your truck the next day. I don't like them, mainly because they don't self cancel, one would get you going though.
 

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Been workin on my 72 F100 all day...total restoration...lots of fun. Putting the interior in today and hopefully I will be posting some pictures soon.
As for the light...go to this website http://www.ford-trucks.com/index.html ...and click on the tech articles...IIRC there is an article on brake light diagnosis.
My bet would be that it is in the column wiring harness...they are a real bear to keep trouble free.
 
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