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.



Views: 222

Reply to This

Replies to This Discussion

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 ! 




  • Add Photos
  • View All


TH400 into 63 SDV

Started by Rick Seiden in General Discussion. Last reply by Tony and Ginny 429 3 hours ago. 2 Replies

After battling with my original trans for several years. Leaks, Shifter getting locked up internally, Torus Seals, More leaks, and finally a professional rebuild that lasted about 3000 trouble free…Continue

Tags: pndlr, prndl, transmission, th400, hydramatic

Timelapse Rebuild of a 1957 Cadillac 365 V-8 Engine

Started by Jason Edge in General Discussion. Last reply by Tony and Ginny 429 10 hours ago. 3 Replies

Saw the link on the CLC forums today and thought I would share to the CLC FB Group. This is a prior generation engine to our 1963-64 390's & 429's but this is a pretty cool time lapse of a…Continue

Classic Cadillac Parts For Sale - Misc Items

Started by Jason Edge in For Sale. Last reply by Jason Edge yesterday. 300 Replies

I have posted a few Misc items over on my Classic Cadillac Parts Facebook page at…Continue

Tags: classic cadillac parts, classiccadillacparts

Blog Posts

bright beam flashes

Posted by Kim K Kaiser on January 9, 2022 at 12:55pm 5 Comments

HI again,

I have the 63 cdv, with the flash assister on the dash,  

My hi lo beams flash back and forth intermittently.  sometimes they dont start flashing at all, sometimes they will just start flasihing on and off until I hit the button on the floor to get them to stop.  sometimes they sound someone is down there hitting the floor button but the lights dont respond, you can hear the click but nothing happens, as if I have no control over that floor button. I have turned off…


Map Light

Posted by RIchard Yasenchack on January 1, 2022 at 8:07pm 7 Comments

I have a 63 Cadillac Series 62 convertible.  Can someone post a picture showing what the map light should look like?

Mine is a meta air vent like grating, which just does not look right for a map light.

Thanks in advance.  Rick

Upgrades for the Coupe de Ville

Posted by Kurt on December 24, 2021 at 6:00pm 4 Comments

At long last I finally have power vent windows! I started collecting the parts 3 years ago. The one thing I could not find until recently is the 6 button driver's switch. Jason finally pulled one in and was more than generous with pricing. Thanks Jason! Installing the vent window motors was the easiest part of the project but many other tasks were spawned by this project.

  1. There is a hole in the door panels where the window crank was. I considered putting a hub cap emblem there…

center bolt size for crankshaft pulley

Posted by Dan Norris on December 6, 2021 at 3:13pm 2 Comments

I need to pull my distributor, and still have the cork in the end of the crankshaft. What is the bolt size needed to thread a bolt in there to be able to turn the motor over with a pull handle and socket to get it to TDC exactly before I pull the distributor out?



  • Add Videos
  • View All

© 2022   Created by Jason Edge.   Powered by

Badges  |  Report an Issue  |  Terms of Service