After finding leak arpund rim of trans pan.  I ordered a gasket.  

I was checking to see if there are any pitfalls or suggestions to getting it right.

I assume drain pan from the drain bolt, then pull the pan and replace.  Will anything drop or fall from the underside of the pan on removal that i should be concerned with.

Views: 194

Reply to This

Replies to This Discussion

Should be flat. Over-tightening them, just like oil pan and valve cover bolts, will pull the pan down around the holes meaning the gasket cannot seat adequately seal the two surfaces. I cannot think o any two mating surfaces on these cars, where you have 3 mating surfaces where they are not designed to be flat.  

Ok,  thanks,  so just get a ball peen hammer n strait edge and tap the bolt holes down flat?


you are asking very good questions regarding your repairs so get them right 


Well, i pounded out the bolt holes all thecway around, used a strait edge to ck flat.  Took greatvcare to rebolt at 7 then 11 pounds,  notvwanting to split another gasket, left itvat 11.  Filled and started engine,  ran a while, shut off, waited went bk to chk.  Leaking along passenger side.  Justva thin smooth layer of fluid justvbelow gasketv on lip. Other side,  bck n frnt were dry.

So, i tighrened up to the 13 lbs as noted in book.  Statred, waited, wentvto ck.  Same result. Thin layer along rim below gasket.

Now thevpan has been put back to smooth per the strait edge.  

Am i missing a step somewhere?  

Did you clean the bolt threads on bolts and tapped threaded holes? You should be able to freely screws each bolt all the way in with your fingers with the pan removed. If bolt holes are filled with gunk the pan will never snug up to the transmission. Also make sure each mating surface is completely clean. Other than that I would lay the pan on a perfectly flat surface, turn off the lights, and use a flash light to go around the edges and look under and check for flatness of pan. 

i cleaned the bolts etc and was able to use fingers to get them flush, before using,, i will pull it again, chk for flat on that side,, something must be off.. i am glad i bought two, figuring on a misstep,, 

Did you put the black rtv on both sides of the gasket? will need to get a new gasket, as the old one has already been crushed into place.

no,, i did not, i seem to have read over at the cad & lasalle forum somewhere that the rtv could come loose, and get into the transmission.  I thought of that but after reading that I decided to leave it off.. 

so, using the rtv is acceptable?

I've never used any rtv sealant on the transmission pan gasket. Why are you using RTV sealant?  Sealing the mating surfaces is the purpose of the gasket? I rarely use this stuff and never on 2 flat surfaces unless specifically indicated in the shop manual. As long as surfaces are clean and flat and screws threads are clean and true you should not need this messy stuff for attaching 2 flat surfaces.

i did not use it on this job.   i had read it was a potential problem if a piece of it came loose or dislodged and got into the system, that was enough to scare me away from it,, 

i will work on it again to day, weather permitting,,,go back over all the info and make sure i didnt leave out a step..

Hi Kim,

I think you may be overthinking it, this is a pretty straightforward operation.  You are probably doing everything correctly but are dealing with a warped pan or substandard gasket.

The edges of the pan may be straight but the whole pan could be warped.  Set the pan bolt flange down on a flat surface and see if it rocks.  If it does, try coaxing it back into shape with your hands.

If the pan is relatively flat, I would look for a higher quality gasket, preferably cork.  You may have to go to an actual transmission shop or possibly the GM dealer may find one for you.  

I suspect you have a very thin gasket.  You are probably torquing correctly but the gasket isn't thick enough to fill the voids between the bolt holes.

There is RTV sealant that is appropriate for use with transmission components.  I generally use a spray tack adhesive just to hold the gasket to the pan for installation.

Final thought:  Are you sure the filter is pushed all the way up into the transmission and is not interfering with pan fit?

Yhanks,  well, i hv a fel pro gaske .  Its a black looks like cork appearance,  i did use a light adhesive to get it to stick.   I will ck the pan again




  • Add Photos
  • View All


Is this possible or total BS?

Started by Kim K Kaiser in 1963/64 Cadillac Specific Discussion. Last reply by Tony and Ginny 429 6 hours ago. 5 Replies

After changing tie rods, i tokk car into wheel n allignment shop. He said no problem.  He calls back about 45 minutes later and said they couldnt get between the tire and cowl, the guys head was too…Continue

Vacuum / Parking Brake / NSS Question

Started by Karl Schwarz in 1963/64 Cadillac Specific Discussion. Last reply by Karl Schwarz 7 hours ago. 2 Replies

I bought a 1963 Series 62 Convertible in July.It makes a hissing sound when in neutral, and sometimes when in drive (when the shift is more to the left that the right. I assume this related to a NSS…Continue

Tail pipe black stuff!

Started by Lambert Ross in 1963/64 Cadillac Specific Discussion. Last reply by Lambert Ross yesterday. 10 Replies

any ideas how to clear the ugly black stuff shooting out from my tailpipe? After a long layover, it really messes up the garage floor. I assume its carbon but am not sure how best to react to it.…Continue

Blog Posts

still need a driveshaft

Posted by wayne weaver on November 26, 2019 at 11:53am 0 Comments

well thank you UPS for losing the driveshaft that Russ Austin shipped me. 

however i still need a rear driveshaft section for my 63. mine has a vibration due to the bushing inside of it. its a shame because the ball and sockets in the cardian joints are perfect but it has a woble on the balancing machine. so .  still need the rear section. anyone have a good one ? is there driveshaft alternatives to use ? i am really considering an LS swap and since im fighting the driveshaft search…


63 guidematic issues

Posted by maurice lapoiinte on November 24, 2019 at 3:10pm 0 Comments

 So my 63 guide matic headlamps stay on low beam all the time. I have so far bypassed the system and everything works normal. I have been thru the trouble shooting in the manual but this is where the confusion begins.on my car when the power relay is powered I have low beam and when its not powered I have highbeam, this appears to be opposite what the diagnosis says should be correct.The wiring is all original and no wires have been mixed up.has anyone ever unplugged the 2 wire connector…


Another advantage of the Pertronix III

Posted by Doug Scarrow on November 23, 2019 at 11:12am 1 Comment

   Having tried both the II and III I can say the multispark feature of the III offers a smoother idle . It is also easier to install .Does not require removal of the distributor

Stuck at two red (dash) lights!

Posted by Jeff Kinzler on November 3, 2019 at 10:00pm 9 Comments

I hope someone can help solve these two electrical problems that appeared one after the other.

By way of background: The car, a '64 Eldorado has very limited use. It was at a restoration shop for 15 months until last January-  that supposedly did a bunch of wiring repairs including rebuilding the gas gauge that still hasn't worked properly, and the clock that hasn't worked, and re-soldering the broken wires in the drive door. All window and seat controls appear to be…



  • Add Videos
  • View All

© 2019   Created by Jason Edge.   Powered by

Badges  |  Report an Issue  |  Terms of Service