I recently inherited a 55 Pickup from my father-in-law.  After a drive from Tampa to Atlanta to bring it home I wanted to change the oil and add some Lucas for the small leak in the rear main.  I thought I had drained the oil completely and proceeded to fill with 4 quarts and a quart of Lucas.  Well apparently the oil did not drain completely and upon checking the oil i am at nearly twice the full limit.  I have tried draining some of the oil out but only a small amount drains wihen I remove the plug.

Since this second gear has begun to make a very high pitched sound but first and third sound just fine.  Have I done something catastrophic here?

Its a 235 6cyl.  Thanks for your help.  

Is it possible i drained the transmission fluid instead?  Anybody know of any diagrams I can consult to make sure I am draining from the correct location?  

the engine oil pan is under the motor...  stamped sheet metal..  only one drain plug..   no levers or shafts sticking out...     usually has a 7/8" headed 6 sided plug with a flat ring gasket on it...


the transmission drain plug is on the bottom of the cast iron transmission... usually it has a square headed plug...  no gaskets.. tapered pipe plug.. 1/2" or 9/16 wrench to take it out..  

there will also be a fill plug just above it..   and shafts with levers and rods on the drivers side of the transmission...


if you have drained the transmission .. do not despair   they car completely rebuildable..  every part is still available.  new or used...

oh... and many 235s have a tiny rear seal leak...    that is the nature of the beasts..

you have to be really good at packing the rear seal in to not have any leak...

something you are not ready for...

if in the future you want to replace the rear main seal..  it is not easy on that one..

you have to use a brass 1/4" roll pin punch and pack the upper half of the already installed rear seal in tighter and add segments to it.  (it is almost impossible to install a new upper half of the rear main rope seal... even with a puller) .  then install a new lower section..  packing it with a socket long before you trim it off...i know that you don't understand exactally what i am talking about.. on this seal packing.. you will later after reading up and learning a lot more..

oh. i don't know what year they changed..  but on earlier gm trucks and cars... you have to pull the rear end back to get the transmission out...  kinda like the newest corvettes..  

Thank you very much.  In my eagerness to charge in a be a do it yourself car guy, I drained the transmission.  One of  those lessons learned the hard way, but not that costly.  I had driven less than mile with the fluid out so while I am sure I have shortened the life, once filled she is running better than before.

I am sure I will come across lots of these little things. Its a shame dad won't be hear to help.  Anyone know of any car clubs in the North Georgia area?  I really need to find some car friends to teach me along the way.

Thanks for your help on my question