Just drove home my new 74 F-100 Custom today. Has four nice 31x10.5 tires, 390 motor. Its original engine was a 360 (5.9L) but now has a nice 390, Edelbrock 1406 (600 cfm), dual exhaust. Front disc/rear drum brakes, PS. Has the cab light, hood light, and glove compartment light (my 77F150 Ranger doesn't have these). Has a small PS cooler too. No factory AC though. No split 4 pc. rear window, just a solid piece.

I've got a couple of questions, hoping someone w/more experience can answer:

1. Transmission code is G, same as on my 1977 F-150. Can someone confirm this is a C6?

2. Rear end says its a 02J (my 77 F-150 is a 13J).

3. The drivers side window crank seems to 'jump' gears and not roll up the window. I thought it was the handle, so I put one from my 77 on the regulator nub, but still acts up. the nub inside the door panel seems loose. Can it work loose? The one on my 77 F-150 works well - hoping that one might be same design as on the 74 so maybe I could change it out?

4. Strange question - the transmission doesn't seem to shift well when going from 2nd to 3rd. It does shift OK when I nail it, but doing a normal easy acceleration it seems to hang up and shift lazy. I noticed there are TWO (not one) steel vacuum lines at the rear of the engine bay (near firewall) that look like they come from the transmission modulator valve. Someone had connected both together then tee'd them to a single vacuum pull off the Edelbrock carb. Can anyone confirm the correct connection of vacuum lines to the 'left' and 'right' modulator valve vacuum lines? does this sound like a defective modulator valve?

Thanks!

 

Congrats on yer new-to-you rig.

1. Tranny code G just translates to a Ford three-speed automatic. If it's an FE with an auto trans, then it's a C6. The bellhousing is round and specific for an FE (IIRC).

2. Axle code 02 is a Ford 9-inch with a 3.00 rear gear. Letter J is for a front axle... in this case, it denotes power steering.

3. Your window regulator is bad. It's not something you can fix... the teeth and crank gears are missing some teeth I reckon. Save yourself the headache and get a decent JY part or a new one.

4. I've never had a C6 but that doesn't sound right. Here's an FTE thread on modulator valve: https://www.ford-trucks.com/forums/1...e-problem.html.

And a pic and caption from: Build A Brute C6


"

 

#3 is the widow regulator teeth inside the door over time the shaft thats connected to the handle gets play in it then makes it strip teeth on the gear of the window regulator and only allowing it to grab in certain spots. pull the door panel off and to the front of the door you"ll see 3 bolts that form a triangle pattern undo those and the one to the lower left that holds the window track n place. pull the regulator back until the wheel fall out of the track on the bootom of the window. Twist and turn the regulator until you get it through the hole. (CAUTION WHEN YOU UNDO THE BOLTS THAT HOLD THE REGULATOR ON, HOLD ONTO THE WINDOW HOLD ONTO THE WINDOW OR IT WILL COME CRASHING DOWN INTO A PILE OF REDNECK DIAMONDS) they make new ones that are 40 bucks from broncograveyard.com Window Regulator, Left

 

Good luck with your new truck

C6 was the only choice back then.

Rear end you just need to find the Ford decoder if its still original gearing.

The window, just replace the entire unit its a PITA to change one of them nubs yes they will interchange.

Take and chuck the modulator and get a signal vac line thats the old style but keep the old one until you get it in and take it for a spin.Most of the time when you have to force it to shift its the modulator.

 

Do you mean chuck the regulator (as in get rid of it)? What is a signal vac line?

thanks-

 

""I noticed there are TWO (not one) steel vacuum lines at the rear of the engine bay (near firewall) that look like they come from the transmission modulator valve.""

Signal typo

Single vacuum line modulator.....

 

Yes there should only be one vacuum line to the modulator.

 

Some C6's came with a vacuum modulator that had two vacuum lines.
Get rid of the dual line modulator and replace it with a "normal" single line version.
The line should go directly to manifold vacuum.
You can fine tune the shift feel by turning the small screw that is in the nipple where you hook the vacuum line.

 

So you're saying to get rid of the two line modulator? Do I just use one line of the two that are on the truck? Lastly rockauto says there are two available valves for a C-6 3 speed tranny of that year w/390 engine: FX189 (two hose connection) or FX194 (one hose connection). I should buy the one hose connection version?