Ford C5 trans lockup function?

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So I purchased a 1994 ford F150 302 with I believe to be a c5 auto. Well it runs very hard on the highway and I noticed it's not going into lockup. I can't seem to find any information on it so maybe yall will help out. How does its lockup work. I know its centrifugal but I need more info than that. Thanks!!!
 
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It would have a 4R70W, Does the Overdrive Off light blink? Does the overdrive light work at all?

You can Google how to flash codes out of your truck.
 
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So I purchased a 1994 ford F150 302 with I believe to be a c5 auto. Well it runs very hard on the highway and I noticed it's not going into lockup. I can't seem to find any information on it so maybe yall will help out. How does its lockup work. I know its centrifugal but I need more info than that. Thanks!!!
Last year for C5 was 1986.
 
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I had a C5 in an 86 t-bird. I never actually felt the lockup engage but saw a "small " decrease in engine rpm when it did lock up on the freeway. I wouldn't have detected it if it weren't the tach which I added. Don't expect a huge drop in engine speed like overdrive would provide. My engine still was spinning flairly fast compared to todays drivetrains and I doubt the function was much help in improving fuel economy. As you know, it is centrifugally engaged and if you suspect an issue, you replace the converter.
 

mpack88

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I had a C5 in an 86 t-bird. I never actually felt the lockup engage but saw a "small " decrease in engine rpm when it did lock up on the freeway. I wouldn't have detected it if it weren't the tach which I added. Don't expect a huge drop in engine speed like overdrive would provide. My engine still was spinning flairly fast compared to todays drivetrains and I doubt the function was much help in improving fuel economy. As you know, it is centrifugally engaged and if you suspect an issue, you replace the converter.
My truck actually has a factory tach and tuns about 3I rpm at 65 and I've never observed a drop in rpm after 3rd gear but I do have a recently rebuild aod I might install. Then it should be like my 88 which turns 2k rpm at 70mph
 
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My truck actually has a factory tach and tuns about 3I rpm at 65 and I've never observed a drop in rpm after 3rd gear but I do have a recently rebuild aod I might install. Then it should be like my 88 which turns 2k rpm at 70mph
That would depend on your final gear ratio in your differential. You would also have to add the throttle cable/ shaft down to the tranny. The C5 uses vacuum. As well as dimensional changes with gear shift linkage and possibly for speedo depending on what year your AOD is. I know on my 87 Merc Cougar, it uses a speed sensor on the AOD for the speedo.
 
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mpack88

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That would depend on your final gear ratio in your differential. You would also have to add the throttle cable/ shaft down to the tranny. The C5 uses vacuum. As well as dimensional changes with gear shift linkage and possibly for speedo depending on what year your AOD is. I know on my 87 Merc Cougar, it uses a speed sensor on the AOD for the speedo.
This aod uses a gear. I know cause I pulled it out.both my trucks are 3.55 8.8 axles. However my 84 uses a smaller tire
 
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