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Discussion Starter #1
Here's my story - bought a 1990 Full Size Bronco a year ago for my son. Just finished putting a new AOD in it and on the test run all was fine until I hit higher speed and it acted like it didn't want to get into 3 or 4th gear, then nothing at all and the engine would rev. NOt knowing why I guess out of desperation I had the idea of locking the front hubs and trying 4WD. It worked by now it won't get out of 4 Low or 4WD. All fluid levels are accurate and I've looked and the TV linkage is still connected. I have search similar threads but I have not found anything quite like this. Thanks in advance!
 

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Satyr of the Midwest
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Putting it into 4x4 and/or locking the hubs wasn't the best plan. Sounds like a broken direct shaft, or a malfunctioning direct hub/clutch pack. I'd make sure the fluid is good and up to level, and then start looking at the filter, and then the valve body for clues.
 

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First of all, welcome to the site :twotu:

Let me ask you this. Does the trans hit 3rd and just rev up (slipping), or does it not even hit 3rd?

I had lost 3rd and 4th in my old AOD, and it was the input shaft that snapped. The torque converter and input shaft is what drives 3rd and 4th.
 

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I don't recall it ever getting to 3rd. Once i noticed the RPMs increasing I let off the gas. Then when I went to accelerate again there was no pulling at all. I let it sit for a bit then I had 1 & 2. I do not know what came over me to put it into 4WD but I did and as I stated earlier it now will not get out of 4WD.
 

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You need to find out if its hitting third. By letting off the gas while its stuck in second, once you press the gas again the RPM's have to build back up to the point of speed that 2nd is spinning before you'll feel the truck pull again. I'm betting on a blown converter or busted input shaft or both.
 

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Discussion Starter #6
So if that is the good news don't hold back what is the bad news. :whiteflag

I think I'm done - calling the shop to bring it in.

Thanks honestly and I hope to keep you posted as to the progress.

Many :beer to ya!
 

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The tranny shop will see you coming and your gonna pay out your @ss for a cheap fix. Trust me.

If your able to pull the trans yourself, you might see the problem right away without tearing the whole trans apart. Both input shaft and torque converter can be replaced very easily.

When it shifts from 1st to 2nd, is it a very firm shift?

I know you said your 4wd is stuck, but that problem is different than no 3rd or 4th.
 

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Discussion Starter #8
Shifting from 1 to 2 is very smooth.

I did speak to a guy who used to do all the local Ford Dealers Tranny work. He has since retired and does somethings out of his house. He told me that it is probably due to the fact that I failed to blow/clean out the cooking lines. Something I didn't think for even read about having to do.
 

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My bet is the tv cable is out of adjustment. I have an aod in my 65' Ranchero and it was working fine. I accidentally heated the spring on the Lokar tv cable and then it wouldn't shift. It had first and maybe second, but once it got into the higher rpms it was like it was just coasting in neutral. A replacement cable and a quick stop at the tranny shop to get it dialed in just right and now it shifts perfectly.
 

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Satyr of the Midwest
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It shouldn't be slipping into neutral and/or free-revving if it's a TV cable maladjustment, though. I'm still standing by my initial assessment of a broken direct shaft or direct hub and/or clutch.
 

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It shouldn't be slipping into neutral and/or free-revving if it's a TV cable maladjustment, though. I'm still standing by my initial assessment of a broken direct shaft or direct hub and/or clutch.
Mine wasn't slipping into neutral, it just acted as though it were in neutral, but only after I hit about 25 mph.
 
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