1968 Chrysler 300 transmission oil leak

bronze turbine

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The pan gasket was just replaced, but it's still leaking. It looks like it's leaking from the pan gasket but it's hard to tell. I think it's a Fel-Pro gasket. Can these pans get bent or is there a better gasket to use? Any other common places these transmissions can leak? Thanks!
 
I agree that it might be the selector shaft seal but there are also better gaskets.
4CD19485-9513-4AC3-B305-F492DB8D0802.jpeg
 
You might also check to see if the pan bolts were over torqued at some point. Applying too much pressure dimples the sealing surface around the bolt holes so that the pan gasket does not properly seat.

Dave
 
You might also check to see if the pan bolts were over torqued at some point. Applying too much pressure dimples the sealing surface around the bolt holes so that the pan gasket does not properly seat.

Dave

I used to have problems with pan gaskets. They went away after I started using an inch pound torque wrench. It's a bit of a PITA as you have to go around several times to get them all tight at the same time. Still takes less time than doing it over, just make sure the pan is sufficiently flat as Dave mentions. IIRC, 12 inch pounds was the spec.
 
The pan gasket was just replaced, but it's still leaking. It looks like it's leaking from the pan gasket but it's hard to tell. I think it's a Fel-Pro gasket. Can these pans get bent or is there a better gasket to use? Any other common places these transmissions can leak? Thanks!
Shift linkage/throttle lever seals leaking. Pretty much a given that they will leak.

TF 727 "How To" shift lever seal replacement
 
Too much pan bolt torque has been known to cut rubberized or pure cork gaskets, even new ones, such that leaks happen soon after replacement. Other than that, shift shaft seals and the neutral safety switch can be culprits. Spray the areas down with brake cleaner, put a big, flat piece of cardboard under the trans, run the car for a while, then shut it off, and see where the drops land.

Enjoy!
CBODY67
 
I'm thinking about replacing the pan and gasket. I haven't yet decided if I should use a stock pan or an aluminum pan. I like the idea of the aluminum pan because it's more rigid and less likely to bend, but I don't really want an extra deep one because of ground clearance issues. Also, is anyone using "Lubelocker" gaskets? They look pretty good to me.

Chrysler, Jeep, Dodge 727- LLT-A727
 
I'm thinking about replacing the pan and gasket. I haven't yet decided if I should use a stock pan or an aluminum pan. I like the idea of the aluminum pan because it's more rigid and less likely to bend, but I don't really want an extra deep one because of ground clearance issues. Also, is anyone using "Lubelocker" gaskets? They look pretty good to me.

Chrysler, Jeep, Dodge 727- LLT-A727
I used one on a 904 because I couldn't get the factory gasket. It's OK, but not anywhere as good as the late factory gasket in the pic. Actually no comparison. I'd use the Lubelocker again for a 904, but for a 727 I wouldn't consider it because I can get this factory piece that is soooooooo much better.

Mopar Part #2464324AC.

Hands down, the best trans gasket I've ever used. Google it and everybody and their brother sells it. And they are reusable!

$_57.jpg
 
I used one on a 904 because I couldn't get the factory gasket. It's OK, but not anywhere as good as the late factory gasket in the pic. Actually no comparison. I'd use the Lubelocker again for a 904, but for a 727 I wouldn't consider it because I can get this factory piece that is soooooooo much better.

Mopar Part #2464324AC.

Hands down, the best trans gasket I've ever used. Google it and everybody and their brother sells it. And they are reusable!

View attachment 474659
That looks like the one that I advertised above. The easiest gasket I’ve ever installed hands down!
 
That looks like the one that I advertised above. The easiest gasket I’ve ever installed hands down!
I don't know... I tried a silicone gasket from Real Gaskets and it was just a flat piece of silicone rubber cut in the shape of my 904 pan.

So... does Real Gaskets repackage the Mopar gasket for the 727 and make their own silicone gasket for the 904? I really didn't care for the silicone gasket although my issue turned out to be something I did, so I can't say it's good or bad. I finally used the Lube Locker, and that I liked better than the silicone gasket.
 
I don't know... I tried a silicone gasket from Real Gaskets and it was just a flat piece of silicone rubber cut in the shape of my 904 pan.

So... does Real Gaskets repackage the Mopar gasket for the 727 and make their own silicone gasket for the 904? I really didn't care for the silicone gasket although my issue turned out to be something I did, so I can't say it's good or bad. I finally used the Lube Locker, and that I liked better than the silicone gasket.
Dang it, wait a minute John. Now that I think about it the Real Gasket wasn’t a rigid one like the Mopar one you pictured above. I confused myself because not only did I just have 2 Trans’ rebuilt but I also had the pan down in my silver car all this spring and I had bought 2 of the orange silicone gaskets and one of the Mopar gaskets. I used 1 silicone one myself on the silver car and gave the other 2 to my trans guy. I will say that my experience with the orange silicone unit was the best and I would buy them again and again. It has 4 holes slightly smaller to hold bolts and the rest of it lays out perfectly flat while you lift the pan against the trans. It also doesn’t help that I just bought the all in one windage tray/gaskets which looks the same. Too many projects…:p
 
Dang it, wait a minute John. Now that I think about it the Real Gasket wasn’t a rigid one like the Mopar one you pictured above. I confused myself because not only did I just have 2 Trans’ rebuilt but I also had the pan down in my silver car all this spring and I had bought 2 of the orange silicone gaskets and one of the Mopar gaskets. I used 1 silicone one myself on the silver car and gave the other 2 to my trans guy. I will say that my experience with the orange silicone unit was the best and I would buy them again and again. It has 4 holes slightly smaller to hold bolts and the rest of it lays out perfectly flat while you lift the pan against the trans. It also doesn’t help that I just bought the all in one windage tray/gaskets which looks the same. Too many projects…:p
The Real Gasket just seemed too "fussy" for want of a better word to describe it for me. It had to be 100% clean and torqued to that real low value. The rigid Mopar gasket was just easier to use for me.

I think it's matter of opinion. Seriously, both will work... It's my opinion that the Mopar gasket is easier to use though.

But, I really think all the gasket conversation is moot. How many times have we had these discussions about changing gaskets to clear up leaks when the real culprit is the shifter lever shaft seals almost 100% of the time? :BangHead:

@bronze turbine Go under the car with some brake cleaner spray and clean off the area around the shifter and the whole pan area. Now hit the area with some baby powder and run the car a little. (A tip I learned here from someone, I can't remember who). Now you will see where the oil is coming from. Dollars to donuts it's running down the side from the shaft seal and running around the pan.

Once you find it's the shaft seal, go back to my posting where I linked the thread on repairing it from outside the trans. The other option is dropping the pan and valve body and remove/replace the shaft seal to the case and the seal on the throttle lever shaft.
 
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The Real Gasket just seemed too "fussy" for want of a better word to describe it for me. It had to be 100% clean and torqued to that real low value. The rigid Mopar gasket was just easier to use for me.

I think it's matter of opinion. Seriously, both will work... It's my opinion that the Mopar gasket is easier to use though.

But, I really think all the gasket conversation is moot. How many times have we had these discussions about changing gaskets to clear up leaks when the real culprit is the shifter lever shaft seals almost 100% of the time? :BangHead:

@bronze turbine Go under the car with some brake cleaner spray and clean off the area around the shifter and the whole pan area. Now hit the area with some baby powder and run the car a little. (A tip I learned here from someone, I can't remember who). Now you will see where the oil is coming from. Dollars to donuts it's running down the side from the shaft seal and running around the pan.

Once you find it's the shaft seal, go back to my posting where I linked the thread on repairing it from outside the car. The other option is dropping the pan and valve body and remove/replace the shaft seal to the case and the seal on the throttle lever shaft.
I’m a stickler for putting things like this back together 100% clean so this was no problem.
 
OK, I have the OEM gasket on hand, now, what about the oil pan? I don't know if mine is deformed but it does have some dents and gouges on it so I'd like to just replace it with a new one. I don't need anything special, just one that is about equal to the original in quality. Any suggestions? Thanks.
 
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