904 and 8 3/4" gasket advice

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Chained_360

Chained_360

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Hi all, I hope everyone is doing well in this strange time we are currently going through. I have a few questions about my upcoming spring project for my 1968 Barracuda: In a couple weeks here I am going to be dropping the transmission to replace the input shaft seal that is leaking badly and I want to do a couple other things while I am in there. The car has a 1978 360, its original 904, and an 841 case 8.75" axle from a '67 Formula S car. All of this is in preparation for bringing the car from Anchorage, Alaska to Indianapolis where i am currently going to school. The tentative plan is to barge it to Seattle, WA and drive it the rest of the way.

Once I drop the trans, I am going to replace the input shaft seal, the pan gasket (and do a fluid/filter change), and the output shaft seal, as well as the engine rear main seal and oil pan gasket as they are leaking too. My question is about the rear axle; I am going to change the fluid in it because I don't know how long it has been, and I'm sure the 3.23 SureGrip would appreciate it. While I am in there, should I also replace the axle seals? The last thing I want to do is blow one in the middle of nowhere and have drenched brake parts. They do not currently leak, so should I just not worry about it? Is it particularly hard to do?

I'm also wondering if you guys have any addition suggestions for preparing this car for the long road trip that will happen in the future. I'm doing full fluid changes, replacing all the old radiator hoses, replacing all burnt out bulbs, and a few other things for comfort. What are your suggestions?
 
oldkimmer said:
U probably need a torque converter because the hub is cracked. Kim
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I suppose I should've described it differently, because I certainly hope I don't need a new converter! It slowly drips fluid when it's running, and after it shuts off for a couple minutes. I'm talking one small drip maybe every 8-15 seconds? I need to add about a half quart of ATF every 200 miles or so.
 
Look for this while its out.
20200313_135102.jpg
20200313_135117.jpg
 
Chained_360 said:
Hi all, I hope everyone is doing well in this strange time we are currently going through. I have a few questions about my upcoming spring project for my 1968 Barracuda: In a couple weeks here I am going to be dropping the transmission to replace the input shaft seal that is leaking badly and I want to do a couple other things while I am in there. The car has a 1978 360, its original 904, and an 841 case 8.75" axle from a '67 Formula S car. All of this is in preparation for bringing the car from Anchorage, Alaska to Indianapolis where i am currently going to school. The tentative plan is to barge it to Seattle, WA and drive it the rest of the way.

Once I drop the trans, I am going to replace the input shaft seal, the pan gasket (and do a fluid/filter change), and the output shaft seal, as well as the engine rear main seal and oil pan gasket as they are leaking too. My question is about the rear axle; I am going to change the fluid in it because I don't know how long it has been, and I'm sure the 3.23 SureGrip would appreciate it. While I am in there, should I also replace the axle seals? The last thing I want to do is blow one in the middle of nowhere and have drenched brake parts. They do not currently leak, so should I just not worry about it? Is it particularly hard to do?

I'm also wondering if you guys have any addition suggestions for preparing this car for the long road trip that will happen in the future. I'm doing full fluid changes, replacing all the old radiator hoses, replacing all burnt out bulbs, and a few other things for comfort. What are your suggestions?
Click to expand...

I think you answered your own question on the axle seals.:D
They are easy to change.

Pump seals do sometimes leak without the converter being cracked just so you know.
You do need to inspect really well while it's out though.
 
Well, I certainly do hope it's just the seal. In the event it's not, is that something that can be patched together with JB-weld or something similar for a short time? The car will be getting a 4-speed conversion in the near future and I don't want to buy a new converter if it's going to come out again anyways.
 
That converter hub is pretty rough. A new seal might not last long there. They may have a speedy sleeve available for those but I don't know for sure.
 
Chained_360 said:
Well, I certainly do hope it's just the seal. In the event it's not, is that something that can be patched together with JB-weld or something similar for a short time? The car will be getting a 4-speed conversion in the near future and I don't want to buy a new converter if it's going to come out again anyways.
Click to expand...
Nope, if it's the converter hub that's fubared, you can also bet that the pump bushing is thrashed too. While changing the seal, (if the hub looks good) also change the front pump gasket and the front pump o-ring. If the transmission is the original one, and has never been repaired, keep in mind that all those items are over 40 years old.
If the hub is damaged, there is no quick fix. I don't understand the use of speedy sleeves(except gypo car lots and questionable transmission people). The hub of the converter must be like a crank journal. Smooth as a babys' butt and so must the pump bushing.
Keep in mind that driving from Seattle to Indy involves mountain passes. First through the Cascade range starting just East of Seattle, and then you have to contend with the Rocky Mountains. Not my idea of having a trouble free drive with a cheapo fix. JMHO
 
The man I bought it from said the transmission has been rebuilt before while he owned it, my guess is they rebuilt it when they put the 360 in. Now, when I bought the car in 2015 the registration tags were for August of 2002. I'm really hoping it's just a dry rotted input shaft seal, but we will see when it comes out next week (or the week after). I'll be sure to keep everyone updated!
 
Chained_360 said:
Well, I certainly do hope it's just the seal. In the event it's not, is that something that can be patched together with JB-weld or something similar for a short time? The car will be getting a 4-speed conversion in the near future and I don't want to buy a new converter if it's going to come out again anyways.
Click to expand...


The hub can be replaced by a converter place if need be.
No. converter hub cracks can't be glued.
Too much stress there.
 
An overfilled trans will blow the excess out the vent.....which is inside the bell house.

The rear seals inner seals will not blow out; there is no pressure in there. The oil level is below the axle tubes and the only way for oil to get up in there, besides over-filling is if you park the car on the side of a hill, with one side higher than the other.
But those inner seals do eventually wear out, but it is very uncommon.I have known them to go a quarter million miles
The outter seals fail more commonly and puke their grease into the brake housings. But these seals cannot be replaced except by removing the bearings first.
Cha-ching.
 
TrailBeast said:
The hub can be replaced by a converter place if need be.
No. converter hub cracks can't be glued.
Too much stress there.
Click to expand...
All converter shops I've been in, and the one I worked for preferred to not just replace the hub. As a matter of fact, I don't remember our shop ever just replacing the hub. Various reasons why, but the one that I remember most was how difficult it was to get the hub lined straight when the converter pump side was still attached to the front(engine side), so to do the job properly, it would be cut in two, and the cost to just replace the hub wasn't that far off of having either a replacement converter, or in the case of a performance converter have it gone through and put it back as new.
 
transman said:
All converter shops I've been in, and the one I worked for preferred to not just replace the hub. As a matter of fact, I don't remember our shop ever just replacing the hub. Various reasons why, but the one that I remember most was how difficult it was to get the hub lined straight when the converter pump side was still attached to the front(engine side), so to do the job properly, it would be cut in two, and the cost to just replace the hub wasn't that far off of having either a replacement converter, or in the case of a performance converter have it gone through and put it back as new.
Click to expand...

Yep, they would have to open it up.
Just thought the cost would probably be less, but maybe not.
 
TrailBeast said:
Yep, they would have to open it up.
Just thought the cost would probably be less, but maybe not.
Click to expand...
And while it's open, clean it, check either the bearing or fibre washer, check the sprag and sprag race. Also, if it's a lockup, the disc on the lockup piston might be contaminated and need replacing as well as the sealing o-ring on the piston. And then, the big issue that could crop up if you didn't go through it properly. What's the warranty and what all is covered. Some industrial converters that bolted together did have a bolt-in replacement hub. The customer could do his own repair with a new hub, and a couple of O-rings. Ahh the good old days.
 
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