Hello everyone. I had a perfectly good shifting Hydra-Matic transmission until I elected to fix the leak at the dip stick tube. I just did a quick seal with gasket maker since my current tube is missing the mount and I was headed to the Lead Sled show in Salina, KS in a few days. I drained about 2 quarts of fluid so I could do a good cleaning around the inlet and under the dirt flange of the tube. Installed gasket maker and reinserted the tube then let it sit for 24 hours. Topped off the fluid level the next night and took it for a test drive and now I only have park, 1st gear and neutral only. I have run the diagnosis in the manual. Reverse table is normal, low table is normal, third table has no 2nd, third or fourth, same results for fourth table per the manual and neutral table is normal. I would think I could assume no broken parts and this is a result of possibly stirring up debris from refilling the transmission. If so if I get into the valve body will I need new seals or is it a take apart clean and reassemble process? Could the governor be suspect and if so should I start there?
On the bright side I did stop the leak.
The valve body is somewhat protected by the filter, and is usually 'self-cleaning'. I actually doubt that silicone would survive long in there. I'd focus first on the governor weights, then drop the pan and clean it out. I would try refilling and running it at that point, only removing the valve body if it still didn't shift. If any debris got into the line pressure feed, it would really not be likely to get past the governor's spool valves and into the passages, but i guess it could potentially.
Thank you again for all your help and knowledge. If the gasket gets here tomorrow I’ll give it a shot!
Thank you much for your explanation and your understanding of the Hydramatic trans
love when a subject gets the attention it does on this super site for our year Super Classic Antique Cadillac owners
It was the governor. Both valves were stuck, a good cleaning and refill and all is good. I was amazed at the torque someone had but on the rear extension bolts. I had to use a half inch impact wrench to break them loose! Same at the universal flange to pinion.
Thank you again for all the help.
Very happy you are back in action with some time and help from your Cadillac friends and minimum expense
Enjoy having her back !