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Discussion Starter #1
so i've got a (basically stock) 1990 bronco with a 302 and an AOD.

first and second gear seem fine, but when it shifts into third, it "clunks" into third, and it feels like the torque converter lock-up clutch is engaged constantly while in third. fourth gear (overdrive) feels the same way.

so my question is, is there an adjustment or easy fix for this? would tightening the kick-down cable help? i'm no AOD expert, but i'm hoping for an easy/cheap fix.
 

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so i've got a (basically stock) 1990 bronco with a 302 and an AOD.

first and second gear seem fine, but when it shifts into third, it "clunks" into third, and it feels like the torque converter lock-up clutch is engaged constantly while in third. fourth gear (overdrive) feels the same way.

so my question is, is there an adjustment or easy fix for this? would tightening the kick-down cable help? i'm no AOD expert, but i'm hoping for an easy/cheap fix.
how do you know if you have a lockup torque converter?

On your problem, make sure your filter and ATF is good. If you have flush the system, you might want todo so now.
 

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Satyr of the Midwest
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Protip: AOD transmissions don't have a lock-up converter like most other automatic transmissions. Instead, everything's done inside the transmission. They employ a small, centrally-located input shaft that engages the front hub of the torque converter, and connects to the direct clutch hub. This clutch is engaged in 3rd and 4th gears, effectively making a "locked" 1:1 input shaft-to-crankshaft speed ratio.

Companies like Lentech make valve bodies that allow you to control this "lock-up" manually with an electric switch, but all it's really doing is controlling a spool valve and solenoid.

DO NOT maladjust the TV cable. Make certain it is adjusted properly, as even slight maladjustment can smoke the transmission easily and very quickly; make sure the grommet on the throttle body is 100% intact.
 

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Discussion Starter #4
i was going to adjust the kickdown cable to be more aggressive (read higher throttle level) it seems to shift too soon anyway.
so the lock up isn't in the torque converter, that's fine.. but it still doesn't answer my question about weather this problem can be fixed, and how to fix it.
 

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Satyr of the Midwest
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I don't see that you have a problem, though. It's supposed to be locked throughout 3rd and 4th gears.

Regarding the clunking, it's hard to say over the Internet. You'd have to probably tear it down if it were an internal problem to see exactly what's up, or find a trustworthy transmission specialist. Those transmissions have some notorious issues, with clunking and squealing being no exceptions.
 

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Discussion Starter #6
so you're saying that a properly functioning AOD is ALWAYS locked when it's in 3'rd and 4'th gear?

the clunking is quite annoying.. well I'll be changing the fluid in it soon, hopefully that will help.
 

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Satyr of the Midwest
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Our 1990 302/AOD clunks going into 4th with a relatively light load. Shifts "normal" when the foot is in it. This had been going on before the rebuild (tranny shop) and after the rebuild. We sorta have dismissed this as normal. It's more of a hard shift clunk.
 

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First off,make sure the tv cable is adjusted to spec using the correct shop manual procedure then re-evaluate the shift concern.
 

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First off,make sure the tv cable is adjusted to spec using the correct shop manual procedure then re-evaluate the shift concern.
+1 on what Bronco1 and Sig said.
The TV cable adjustment on an AOD is critical to proper operation and long service life. I can't stress that enough.

Also be aware that for for a few years Ford had a problem with the tv cable hook up on the throttle body, meaning that the dern connection would break and simply fall off. Most usualy,within 50 miles of that happening, the transmission was toast.
The root cause of the problem was the cheap-ass plastic/rubber/snap together materials that was used. There is a (metal) service kit to address that. Ford has them and I think(?) that I remember buying a simular kit from NAPA once or twice. I can't remember what all years would be effected by this but if I had an AOD equiped vehicle, it is certainly something that I'd look into before I drove it another step.

DGW
 

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shibby
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i was going to adjust the kickdown cable to be more aggressive
Key thing here- it's not a kickdown cable. It's a TV cable- throttle valve.

A kickdown cable on a C6 does a totally different thing than a TV cable on an AOD.

Just wanted to get the terms right.
 

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Man I hate to tell you and many will tell you here that the AOD is a clunky transmission. The only thing to do is make sure the TV cable is adjusted properly. If not you can ultimately kill the trans with a few miles.

Mine does it. I adjusted my TV cable slightly and it's a little better now.
 

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There mis a video here that describes how to properly adjust the AOD. I adjusted mine according to the video, and it works fine. No more squeels, or clunking. It does shift into 3rd very soon, but I can live with it.
 
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