Transmission / Overdrive: Delay

[plee4139]

My '56 Sky Hawk with Flight-O-Matic won't go into Drive until the engine's been running for awhile. The fluid level reads full, and it shifts fine after that.

[bosshoss61]

I've had plugged tranny coolers that will do that. Or maybe a vacuum sensor somewhere on the tranny....

[Warren Webb]

Peter, when was the last time you changed the transmission fluid? Smell it & if it has the odor of being burnt, then change it including the torque converter. FOM transmissions do not have a vacuum modulator. Pressure is regulated by a linkage to the throttle assembly. If you transmission is not air cooled & has cooler lines, then blowing them out when you change fluid is always a good idea.

[plee4139]

I've had the car for 5 1/2 years and put 10k miles on it. The transmission was taken off another car and put on mine when the car was restored about 6 years ago, so I guess the fluid had to be changed to do that. Should I have it serviced if it runs fine otherwise?

[Warren Webb]

It couldn't hurt.

[studegary]

I've had the car for 5 1/2 years and put 10k miles on it. The transmission was taken off another car and put on mine when the car was restored about 6 years ago, so I guess the fluid had to be changed to do that. Should I have it serviced if it runs fine otherwise?

The fluid may not have been changed then. Even it was, IMO you are overdue for a change anyway.

[SN-60]

Peter, when was the last time you changed the transmission fluid? Smell it & if it has the odor of being burnt, then change it including the torque converter. FOM transmissions do not have a vacuum modulator. Pressure is regulated by a linkage to the throttle assembly. If you transmission is not air cooled & has cooler lines, then blowing them out when you change fluid is always a good idea.

I believe a 1956 Flight-O would be air cooled.

[SN-60]

My '56 Sky Hawk with Flight-O-Matic won't go into Drive until the engine's been running for awhile. The fluid level reads full, and it shifts fine after that.

Is this delay something that happened suddenly, or has this delay happened gradually and is getting worse?

[StudeRich]

It has the most common failure of very Old Borg Warners, and probably ALL Automatics, the Clutch Drum Seals are cooked.

[plee4139]

It's been going on for a while and has remained the same.

[plee4139]

That sounds like a very expensive rebuild job to me.

[gordr]

Go to the auto parts store, and buy a can of Trans-X. I believe it is made by K&W, but if I am wrong, someone will let me know. It contains a seal softener, and is often effective in this sort of condition. It won't "cure" the problem, but it may delay the inevitable rebuild for a few months, even a few years. I'd warm the car up, pour in the product, then go for a drive of 50 miles or more to give it a chance to work.

[plee4139]

I think that as long as it shifts fine I can live with the delay getting it into gear when I first start it up. Frankly, I'm afraid putting any additives in might screw it up more. Call me cautious.