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Strange transmission seal issue

AR67GTX

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Not sure what to make of this - 66 Satellite 4 speed. I’ve driven the car 6 or 7 times and not found any transmission leaks (it does have oil in it). I moved it from one garage to another 3 or 4 days ago, running the car about 5-10 minutes in the process, and parked it. No transmission leaks or spots on the driveway. I went out this morning to start it up to take it to lunch and upon backing out I noticed a big puddle of oil on the floor about 10 - 12” in diameter. I would guess about 4 - 6 oz worth. It looked to far back to be from the engine and felt like heavy oil. Looked under the car and could see a drip hanging from the rear transmission seal area. Crawled under it and that’s definitely where it came from. The boot on the seal has a small hole on the bottom that I guess is an intentional weep hole if the seal starts leaking. Except for the one drip hanging from the seal it didn’t loose any more oil in getting the car back in the garage. The yoke and bushing feel snug - no excess play.

Probably just going to lead to a new seal - no big deal - but what would make a 4 speed all of a sudden, just puke a bunch of oil past the seal. And after it’s parked and shut down???
 
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Does your transmission have a vent? I am an automatic guy, so not sure about 4-speeds. I am thinking a non-working vent could lead to the whirring gears being able to build pressure in the trans to push oil past the seal.
 
Pretty sure I felt one up on top but haven’t studied it or tried to remove it. I plan to put it on my lift tomorrow so I can study it a little closer. But strange thing is this stuff all came out after the car was shut down and parked - no drizzle trail into the garage or spot where it was parked in the other garage. Very strange.

Do Mopar yokes have any issues with leaks near the u-joint seats from the bores?
 
Your leak is minor. One ounce of oil on concrete would have a 12 inch spread. Verify the level and go from there.
 
There is a vent on top of the tail shaft housing it is pressed in.
 
I had 4 speed that the vent was not drilled out from the factory it leaked from every place except from the vent. The transmission warmed up and the gear lube seeped out. It was a greasy mess. I don't think your problem is a blocked vent. Just my guess.
 
I have seen front yokes with a plugged hole in them. Maybe the plug came out.
 
That’s something I’ll check when I put another seal on. Trying to find a double lip read seal and still looking.

I disagree A 12” pool of gear oil is a minor leak. Gear oil doesn’t flow out quite as much as engine oil and it stacks up thicker. It was on a sheet metal drip pan I keep under another car and it was quite a bit to mop up with paper towels. Not normal at all for sitting 2 or 3 days and it gives me the impression it puked it out all at once when I parked it. When I started it and backed it out yesterday and parked it again, I found one small dot on my driveway and when I crawled under it a couple hours later I didn’t see evidence of it leaking any more. Need to check it this morning. Very strange to do something like this randomly.
 
Opps - got the car up on the lift. No more mass pukes of gear oil but some dripping out of seal boot weep. However, when I earlier tried to wiggle the yoke earlier to test for bushing wear I apparently just did so side to side, and indeed it feels pretty good like that. But up and down is another story - pretty loose. So that has probably done in the seal.

So looks like I need to be looking for one of those in-car bushing remover tools Miller used to make. I think Brewers may have them.

Anyone use one of theirs? OK quality?

Does the tool also work to drive the new bushing in place?
 
Check e-bay for the tool and yes it includes the driver for the bushing. Good luck getting a bushing that is any tighter. The factory bushing was machined in place, all others will be loose. Feiock performance sells a coated c-6 bushing that is tighter, c-6 and 727 are the same, other than the drainback hole, durabond sells a coated bushing but I do not know if it is tighter as they are backordered.
 
If you have no vibration at 50-70 mph, and the yoke is not scored, do yourself a favor and just change the seal.
 
I’ve read that some of the tools break easily. I figure Brewers are probably decent quality. EBay - don’t know?

I haven’t owned the car that long or sorted it all out. It has some vibration but how much is from the 10 year old BFGoodrich tires and how much from the oblong worn bushing no one knows. I had a worn bushing in a Muncie once that definitely caused vibration. The condition of the yoke remains to be seen.

thanks
 
Brewers is fine, new yokes are a little small Pic shows the bushings, the coated one is tighter and am pretty sure once beat in it will get to the .005 clearance, the common brass ones end up at near .010, factory babbitt is about .007 but I can't get them lately, so I have been hard chromium the yokes and using the durabond. Waiting on the durabond bushing, they say mid may or so, hope it is still tighter like the fieock performance, otherwise I will make a drain hole and groove in the feiock and run it. I think when these cars sit a long time, and the trans is not 100% full, the bushing goes dry and when you first drive it gets a scratch or score mark, then it gets worse from there. Jack them up from the front so the bushing gets lube for an hour I guess after long periods of downtime. Anyway that is what little I know, it is a problem

20220410_164900.jpg 20220410_164848.jpg 20220410_170332.jpg
 
Opps - got the car up on the lift. No more mass pukes of gear oil but some dripping out of seal boot weep. However, when I earlier tried to wiggle the yoke earlier to test for bushing wear I apparently just did so side to side, and indeed it feels pretty good like that. But up and down is another story - pretty loose. So that has probably done in the seal.

So looks like I need to be looking for one of those in-car bushing remover tools Miller used to make. I think Brewers may have them.

Anyone use one of theirs? OK quality?

Does the tool also work to drive the new bushing in place?
Have the tool. Your box is full.
tb1.jpg
 
I’ve read that some of the tools break easily. I figure Brewers are probably decent quality. EBay - don’t know?

I haven’t owned the car that long or sorted it all out. It has some vibration but how much is from the 10 year old BFGoodrich tires and how much from the oblong worn bushing no one knows. I had a worn bushing in a Muncie once that definitely caused vibration. The condition of the yoke remains to be seen.

thanks


On the tools breaking I have heard the puller threads strip, on any puller threads it is wise to clean them well and lube with gl-5 gear oil or some other high pressure lube, it's a $100 tool not $500 like oem one.
 
That’s generous Fran. Already sent an order in to Brewers this afternoon. They only wanted $100 for the tool and I figured with the car guys I hang around with it doesn’t hurt for one of us to have one of these. If Brewers blows off my order, I’ll holler back to you though. Never know - I ordered a gauge from Autometer 12 days ago and they took my money and I haven’t heard a word out of them yet!

thanks again
 
Here is the durabond, one piece tubing, no seam like the others, coated, no drainback hole, measures the same as the fieock coated bushing.

20220412_192800.jpg
 
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