Transmission leak on 1966 DeVille

[Cadillac-son]

I'm new to the forum and would like a bit of advice from someone knowledgeable.  I've got my late father's 1966 Deville convertible with a transmission leak.  It's dripping from the bottom of the bell housing.  Haven't looked at it closely yet, so I'm not sure exactly where it is originating from but I do know my father would just add fluid as needed.  I'm wondering if anyone knows if the front seal can be replaced without disassembling the transmission?  I'm hoping that the transmission can be dropped and the front seal replaced from the outside.  I searched the forums but didn't find anything this specific.  Thanks for any help anyone can offer.   

[bcroe]

There are MANY places here transmission can leak.  I would first see that
the easy fixes are taken are of.  The one you cannot change without
removing the trans and probably needing dis assembly, is the front seal. 
It might fail because of a bad front bushing, that will require pulling
the front off and pump coming apart. 

As for myself, I fix the leaks causing a lot of fluid loss.  Never seem to
get them all, so its parked over a drip pan.  Just had a discussion about
this here.  good luck with that nice switch pitch trans, Bruce Roe

[Cape Cod Fleetwood]

I'm new to the forum and would like a bit of advice from someone knowledgeable.  I've got my late father's 1966 Deville convertible with a transmission leak.  It's dripping from the bottom of the bell housing.  Haven't looked at it closely yet, so I'm not sure exactly where it is originating from but I do know my father would just add fluid as needed.  I'm wondering if anyone knows if the front seal can be replaced without disassembling the transmission?  I'm hoping that the transmission can be dropped and the front seal replaced from the outside.  I searched the forums but didn't find anything this specific.  Thanks for any help anyone can offer.

Brian I think its WONDERFUL you have your Dad's Caddy, a story close to my heart, trust me.
Do the right thing, have the tranny pulled and professionally rebuilt by a shop with a rep doing old
cars. You might have to wait a bit in line, but it will be worth it. Figure 1-1.5K depending on where you
live. This will be a one and done issue. And I'll give you a 'may as well' since its not expensive - have the drive shaft sent out and rebalanced, and the rear end drained and refilled with fresh fluid and new seals front and back. Now your drive train is DONE. Pictures please and keep us in the loop with this family car.

[bcroe]

If the trans is original, it is way over due for a refresh.  Lower miles, you
may be able to replace seals, keep your hard parts that may be better than
new from across the ocean. 

VERY IMPORTANT, you want to KEEP your trans a switch pitch.  Many shops
are not familiar, and just THROW AWAY your switch pitch parts. Be sure that
does not happen.  Bruce Roe

[signart]

The front seal can be easily replaced without any disassembly, but of course the trans would have to be removed.
But, while it is out, I would remove the pump and at least replace the o-ring and gasket. If the transmission works perfectly, I would leave it alone besides that. If it is giving any trouble at all, I would go for an overhaul while it is out.
400 turbo probably the least expensive transmission to repair as far as parts & labor, especially if you do the R&R.
Also the best transmission ever produced imho.

[Cadillac-son]

Thanks everyone for your advice.  My father did a frame-on restoration about 15 years ago and had the engine and transmission rebuilt then.  The car is 330 miles away from me at my mother's house and I'm going to drive it to my house and fix a number of items that are not working properly; the climate controls and A/C, electric antenna, electric seat mechanism, clock, windshield washer, and of course the transmission leak.  The transmission works well otherwise.  A bit of an adventure coming up with the drive to my house.

[scotth3886]

I'm new to the forum and would like a bit of advice from someone knowledgeable.  I've got my late father's 1966 Deville convertible with a transmission leak.  It's dripping from the bottom of the bell housing.  Haven't looked at it closely yet, so I'm not sure exactly where it is originating from but I do know my father would just add fluid as needed.  I'm wondering if anyone knows if the front seal can be replaced without disassembling the transmission?  I'm hoping that the transmission can be dropped and the front seal replaced from the outside.  I searched the forums but didn't find anything this specific.  Thanks for any help anyone can offer.

Are you sure it's tranny fluid?  That's just about where a rear main seal will deposit engine oil on the ground too.  If by chance it is engine oil, a rear main seal is a relatively easy job. 

[Cadillac-son]

I know that my father said it had a tranny leak and when I was last at the car and checked it was low, so I'm pretty sure but I haven't physically checked the fluid.  That will be the first thing I do when I get to the car.

[Michael Petti]

I had the same issue with my 60 CDV. I found a shop that was knowledgeable about older transmissions. A friend referred me. It leaked but otherwise ran perfectly. He removed it, resealed it, stopping most of the leaks. he was honest enough to tell me that the rear pump was leaking a very little but it would cost double to pull that and repair it. I left that alone and it leaks maybe a half a pint a year. The key to me is to find the right shop.

[Michael Petti]

I also agree that its best to keep as many original parts as you can. Todays parts can be of dubious quality.

[Roger Zimmermann]

I had the same issue with my 60 CDV. I found a shop that was knowledgeable about older transmissions. He removed it, resealed it, stopping most of the leaks. he was honest enough to tell me that the rear pump was leaking a very little but it would cost double to pull that and repair it.

The rear pump was used till 1958. Your 1960 transmission has no rear pump, but the external look between a 1958 or 1960 transmission is the same!

[Michael Petti]

So maybe he was not as knowledgeable as I thought, but the trans still works good and leak is very minimal.

[signart]

Your '66 trans is not at all complicated as the ones before it... or since. A fifty dollar bill will buy all the seals & gaskets needed to seal anything that can leak on there, plus the cost of a filter if you change that while installing a pan gasket. You may only need the front shaft seal which has the same type seal and procedure for replacement as the tail shaft seal. (once the transmission is removed)

[Cadillac-son]

Thank you everyone for the great advice.  I'll let everyone know how it turns out.