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40 Deluxe · 04-05-2012, 02:37 AM

Could one of the servo supply tubes be cracked or deformed and leaking?
Now, I'm going from dim memory here, but it seems I remember that case cracking wasn't a problem until the CruiseOmatic came out, with the sprag or one-way clutch that enabled the trans to start out in first instead of 2nd (the rear band was not needed except in manual low). The stationary part of the sprag was anchored to the case with a special long servo mounting bolt in the center of the case and the extra strain of shifting into gear at high idle (or doing a 'neutral drop'!) is what broke these cases. Your trans doesn't have the sprag but could still be cracked, I guess. Just drop the pan, pull the front servo and look for a crack at the bolt hole. As I remember, this cracking affected 2nd gear as the front servo could now flex and move when the band was applied. A crack would not cause a pressure loss as there are no oil passages in the case; those tubes are what carry the pressure to the servos. Also, I remember something about an aluminum insert either in the back end of the input shaft or front end of the output shaft that carries oil somewhere. This insert can come loose and cause problems (it may only be on the Cruise-O-Matic; not sure). Old shop manuals have pictures on how to check.
It's been over 25 years since I've been into one of these trannies so I may be a little vague.

04-05-2012, 02:37 AM	#12
40 Deluxe Senior Member Join Date: May 2010 Location: now Kuna, Idaho Posts: 3,778	Re: Help with a Fordomatic transmission Could one of the servo supply tubes be cracked or deformed and leaking? Now, I'm going from dim memory here, but it seems I remember that case cracking wasn't a problem until the CruiseOmatic came out, with the sprag or one-way clutch that enabled the trans to start out in first instead of 2nd (the rear band was not needed except in manual low). The stationary part of the sprag was anchored to the case with a special long servo mounting bolt in the center of the case and the extra strain of shifting into gear at high idle (or doing a 'neutral drop'!) is what broke these cases. Your trans doesn't have the sprag but could still be cracked, I guess. Just drop the pan, pull the front servo and look for a crack at the bolt hole. As I remember, this cracking affected 2nd gear as the front servo could now flex and move when the band was applied. A crack would not cause a pressure loss as there are no oil passages in the case; those tubes are what carry the pressure to the servos. Also, I remember something about an aluminum insert either in the back end of the input shaft or front end of the output shaft that carries oil somewhere. This insert can come loose and cause problems (it may only be on the Cruise-O-Matic; not sure). Old shop manuals have pictures on how to check. It's been over 25 years since I've been into one of these trannies so I may be a little vague.