Overdrive light not working
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7th Gear
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Overdrive light not working
95 f150 4x4 Eddie Bauer. overdrive light did not illuminate when button pressed. TS down to bad switch on the automatic gear shift ****. Replaced same switch now light illuminated when pressed. My question is how do I tell if the overdrive is working. I would guess that the rpm would be lower at freeway speeds or different shift points when accelerating. But I am not sure how to verify. Any guidance is appreciated.
Fleet Owner
Joined: Jul 2006
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From: Mi'kma'ki
Very simple, just press the button when you think you should be in top gear. Probably 45mph, under light load, like stated. If it doesn't downshift you know you're still in 3rd. If you don't feel any change, just take up to 55mph to be extra sure and try it again there.
To test convert lock, while going 45mph under light load, keep your right foot on the accelerator and gently apply pressure to the brake pedal with your left foot; just enough to turn the brake lights on, not enough to ride the brakes hard. You should feel the converter unlock and gain a couple hundred rpms. Not as drastic as the when you press the OD button and downshift to 3rd.
Another way to test the OD button, is to find a nice downhill grade. While going downhill, press the OD button to downshift into 3rd and you'll feel it hold you back. This is helpful while loaded/towing in general, to help from smoking your brakes. With an F150 and 302 combo, you may find it useful to use the button to help prevent gear hunting (between 3rd and OD) at specific speeds, but in HD diesel applications, this is the only time we find the button useful.
To test convert lock, while going 45mph under light load, keep your right foot on the accelerator and gently apply pressure to the brake pedal with your left foot; just enough to turn the brake lights on, not enough to ride the brakes hard. You should feel the converter unlock and gain a couple hundred rpms. Not as drastic as the when you press the OD button and downshift to 3rd.
Another way to test the OD button, is to find a nice downhill grade. While going downhill, press the OD button to downshift into 3rd and you'll feel it hold you back. This is helpful while loaded/towing in general, to help from smoking your brakes. With an F150 and 302 combo, you may find it useful to use the button to help prevent gear hunting (between 3rd and OD) at specific speeds, but in HD diesel applications, this is the only time we find the button useful.
Last edited by FORDF250HDXLT; Apr 6, 2026 at 12:21 PM.
Fleet Owner
Joined: Jul 2006
Posts: 20,396
Likes: 866
From: Mi'kma'ki
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