Transmission won't shift into any other gear

[ChrisDiehl]

1985 f150 xlt lariat. I just bought it from my cousin knowing it had a few problems. Anyway I can shift from park to reverse fine. I shift into drive and it stays in 1st. What could it be?  Is it time for a new transmission?  And does anyone know what transmission came in this year truck?  I've been told it's a c6 and an AOD.

[Gary Lewis]

Chris - Welcome to the forum!  Glad you joined.  

You probably missed the email that Scott just sent you to go to the New Members Start Here folder, read the guidelines, and then introduce yourself by starting a new thread in that folder.  Many people somehow miss that step, but it is important as we hold people to the guidelines and want to ensure you've had a chance to read them.  Have you?

On the transmission, both AODs and C6s came in these trucks.  But the AOD only came behind the 302 and sometimes the 300 six.  So if you have a 351W or larger it will be the C6.  However, you can tell by decoding the certification label that is on the driver's door post by going to Documentation/Specifications/Certification Label in the menu.  Or, directly to Documentation/Specifications/Transmission Codes.

How long has the truck sat?  I ask because I know that the C6 can get gummed up after sitting for years and not shift properly.  So tell us more about the truck and what's been done to it.

[ChrisDiehl]

Sorry for not introducing myself. I'm anxious to get working on the truck and I have a long list of questions that google hasn't helped me with. There's a fine line between googling for hours to just end up asking the questions to an audience that already knows the answer.

I'm pretty sure it was driven periodically to keep everything lubed up but I'll ask the previous owner in a bit. It has a 302 in it and he said it had a c6 in it but I went to a transmission shop and the guy said that an 85 would of had an AOD in it. He told me it  was shifting fine and a few days before I bought it it wouldn't shift out of 1st all of a sudden. He's my cousin so I tend to believe him. And I only paid a 1000 for the truck.

[Gary Lewis]

Have you read the guidelines?  If not, please do so.

As for the transmission, you should confirm what it has, or at least came with, via the methods I mentioned above.  That's because the two transmissions are quite different and we need to know what we are dealing with.

[LARIAT 85]

The easiest way to tell what automatic transmission you have is to just look at the gear indicator on the dashboard.  

If the shift pattern looks like this:

P  R N D 2  1

...then you have the C6.



But if it looks like this:

P  R N OD D  1

...then you have an AOD, or Automatic Overdrive.


Capiche?

[ChrisDiehl]

Looks like I have an AOD then. I also found the transmission code on the door sticker and it's T which also indicates an AOD. So OD is 4 gears, D is 3 gears and 1 is.....well useless.

[Gary Lewis]

The AOD uses a Throttle Valve (TV) linkage from the throttle.  It requires a precise adjustment or the tranny can be damaged.  So the first thing I'd do is read the factory shop manual section on the AOD at Driveline/Transmissions/Automatic Transmission/Automatic Overdrive (AOD) and adjust the TV linkage per the instructions.

Beyond that, I'm not much help.  Don't think I've ever driven a truck with an AOD, and certainly haven't owned one.

[LARIAT 85]

That's good.

Does your truck have a carburetor or is it fuel-injected?  That makes a difference as far as trying to find out what the problem is.

[ChrisDiehl]

It's carbureted

[LARIAT 85]

ChrisDiehl wrote

It's carbureted

What carburetor does it have on it?  If it isn't the factory 2-barrel Motorcraft carburetor with the AOD specific linkage and TV rod, then you have a problem.  

Can you take a picture of it from the driver's side?  I would like to see exactly what you have and the the transmission linkage.