Hi all, new to the forum. I just recently purchased an 84 F150 SWB with the 302 V8 and a (I believe) C4 transmission. When I drove it home, it ran fine, except that it feels like it only goes from 1st to 2nd gear. When I am running 55 you can hear the engine whining. When I coast after hitting 55, the truck lugs like it is in low gear. I can't seem to get it figured out. I looked underneath today at the linkage. Here are a few pictures. By the way, when I get to 55 or so, the motor stalls out like it is flooding. It appears I may have inherited a turd.

By the way, look for the magical power steering pump cap!





What is missing? What is that linkage?





At least the outside is working.


Well, I got the thing for $680, so I am not too upset. However, I'd like to get it all working again. I have read the carb could be running rich, causing it to stall. But I am more of the idea that to get to 55MPH, I am running the RPMs up way high and causing some intake issues. The transmission thing is the big sticker right now. I am well and prepared to fix the leaks as it appears I have a tranmission and engine leak. This poor truck has been beat on by the PO. I am dedicated to bringing her back to life.

 

Missing linkage is for the kick-down rod.
Pics don't really tell the whole story, but that could be a C4. The C6 was offered in 84, but it appears your truck originally had the AOD, so there's no telling what the PO may have swapped in to replace it. The C4 was not offered in trucks in 84.
Make sure the modulator valve has vacuum to it. The valve could be bad, as well.

 

Just to add to this:

1) Went outside and disconnected the shifter linkage. It appears that I have 6 positions when I manually move the shifter (PRND21). However, when the linkage is connected, I only get 5 positions. Really odd. So when the linkage is connected and I shift from the cab I get PRND2. I know this is the case because I adjusted the linkage and took it for a drive. I tested Park, Reverse, Neutral, Drive, and when I upshifted, it stayed in second. Under no circumstances is the truck moving to third gear. Any advice is GREATLY appreciated.

2) I found a few vacuums that are disconnected. One is on the back of the carb and the other is on the side of the carb. I am not sure what this means. I am really starting to curse the previous owner. It appears the powertrain is jacklegged by someone with no business under the vehicle.

 

I can take a better picture if needed. What picture can I take to make 100% of the transmission? I figure the truck originally came with an AOD. The shift indicator does NOT match the C4 gears.

 

A good shot from directly under the pan will tell quite a bit.
Those disconnected vacuum hoses could be part of the problem. Without vacuum getting to the modulator valve, the 1-2 shift will be very late, and sometimes they will never shift to 3rd.

 

Identified...It's got to be a C6 transmission.

I have to admit, I am half tempted to drop the pan on that transmission. It is leaking terribly.

 

Pic doesn't show, but if square with on recessed corner, it's a C6.

 

I looked where I thought the modulator would be and instead I found the dipstick.

 

Modulator is right above the recessed corner on your C6. Pic shows this time, and it is a C6.

 

Disconnects:


Thought these two might connect, sadly they do not fit. That hose goes to the bottom of the carb.



Something off the radiator


Thanks for the answers so far. I had been thinking I had a C4 until I looked at the pan.

 

There is a vaccuum at the modulator. In fact, when pulled the idle isn't as smooth. I tested it and it is pulling a vaccuum.

 

Well, that confirms that it is hooked up, and correctly. Did any fluid drip from the hose or valve? It still could be bad.
That's quite a mess of hoses that are unhooked. I'd start by seeing if any of them seem to be pulling vacuum. Also look for any uncapped vacuum ports on the carb or intake. Vacuum leaks can make an engine run lousy, and prevent an auto trans from working correctly.

 

No fluid came out of the modulator or hose.



I think this one belongs here...I am ordering a Haynes manual for this vehicle today. There are still several disconnects.

 

The picture posted above must be correct. That hose was pulling major vaccuum. Now the truck has power and doesn't stall, but I still lack 3rd gear.

 

Choke pull-off. I bet that really perks up the old truck.
It's possible that the trans needs attention, but I'd wait for a few opinions from other that are far more knowledgeable about auto's than me. I just know enough to answer a few basic questions. Auto trans and EFI are my weak points. Never took the time to learn about them.