T-85 Overdrive

Clutch, transmission, rear axle

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hi-fi-guy
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T-85 Overdrive

Post by hi-fi-guy »

I have a T-85 3 speed overdrive transmission on my truck. Can someone tell me how to test the overdrive part of it? The guy I bought it from said he had "disconnected" it, but from what I've read I don't see how he could have done that. The cable that comes from the overdrive handle goes down under the truck but then isn't connected to anything. Maybe this is what he was talking about, but wouldn't that only disable the overdrive lockout and not the overdrive itself?
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SportCustom
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Post by SportCustom »

He may have disabled the switch in the cab as well, look under your dash at the pressure switch that the gas pedal actuated at WOT and make sure that that is hooked up, You will also need to reconnect the cable that you found disconnected from the overdrive handle.
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peanutman
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Post by peanutman »

Depends. It may be shifted out of overdrive. Shift lever in other direction by hand and try it, if still nothing you should have 2 solenoid type switches on tail housing of tranny and switch on fire wall. Could be disconnected from any of these spots. Did he say why he disconnected it :?
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hi-fi-guy
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Post by hi-fi-guy »

Went out and looked under the truck and it looks like I might not even have a T-85 in the truck anymore. There is no solenoid housing on the tranny itself. The truck came new with a T-85 as the switch on the firewall and VIN code indicate, but the transmission must have been replaced at some time. Where on it would I look for and ID number?
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peanutman
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Post by peanutman »

A t-85 tranny will have an extended tail housing with two solenoids one on each side,one toward back and one almost middle ways, side plate on tranny will have a D shape and bolt pattern. po probaly ran into problem i have, parts are hard to find for those tranny's. He probaly changed to a ford 3.03, they are low cost and easy to find. My tranny's id #t89b-148 stamped on shift plate.
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edselehr
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re: T-85 Overdrive

Post by edselehr »

Lower drivers side solenoid is the one that electronically engages/disengages OD at speed. The upper item is the speed governor, which tells the solenoid when the speed is okay to engage or disengage.
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