A904 real seal questions

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Abodysrule

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I put my driveshaft in and I noticed the real seal boot was folded in on itself, see first pic. No problem, I took a soft plastic tool and unfolded it, see second pic.

I've never noticed a raised lip on the end of the boot, could it be that it was supposed to be folded under so that lip seals on the shaft?

a.jpg


b.jpg
 
The actual seal is inside, that is just a dust boot. Looks like the driveshaft may be a bit too long?
 
Oh yeah, I know the real seal is inside, I was just asking about the boot. thanks.
 
OK, so question to the forum. How much distance should there be between the end of the tranny tailshaft and the yolk? Looks like mine is a bit tight, I have 1 1/4". I can have the drive shaft shortened, just need to know if I need to and if so by how much.

Brian
 
To Measure; all 4 wheels need to be on the ground and the suspension at normal ride height.
If the rear wheels are hanging,
the rear end has swung forward on the front spring segments and pushed the driveshaft forward.
In the pic, I agree that the rubber boot should not be touching the yoke, which would burn it off in no time.

I can't say for sure but IMO the boot is not there to keep dirt out of the seal. IMO it's there to collect any ATF leaking past the seal, and drip it out the little hole at the bottom, onto the street, instead of all over the bottom of your car.
That it keeps the dirt off the seal is IMO just a bonus.

In years gone by, it might have made it possible to drive thru water deeper than the tail, but that was like 80 years ago. If you drive thru water that deep, yur gonna have lotsa other worse problems.

I could be wrong and I don't care. If mine doesn't have a hole, I drill one.
 
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My car has all four wheels on the ground. There isn't a hole in the boot.

Any others want to opine if I have enough distance between the yoke and the tail end of the tranny?

Does the driveshaft move forward and back more than 1" during normal operation?

B
 
Abodysrule said:
Does the driveshaft move forward and back more than 1" during normal operation?
Click to expand...
No, not even close.

When I measured for driveshafts on my 68 and 66 Darts, both only showed about 1/8" - 3/16" difference from full compression to full droop.

Most driveshaft shops will have you insert the yoke all the way in until it stops, take a centerline measurement on front and rear u-joints, then subtract about 3/4". How much does your yoke go in the trans? and what is the difference between that and the first photos you posted?
 
I'd have to measure....but, what about the boot on the seal? It interferes with how far I can insert the yoke, does that count? I know that I could insert it far enough to get the rear u joint past the cradles in order to seat it and bolt it in...
 
OK, I wrote to my transmission guy; he said it should be 1" from bottoming out. That's where it's setting almost exactly. b
 
Abodysrule said:
OK, I wrote to my transmission guy; he said it should be 1" from bottoming out. That's where it's setting almost exactly. b
Click to expand...

If that boot is left unfolded you will probably be smelling burnt rubber, or it could actually catch on fire from the friction.
I would cut that boot off.
Lots of these cars never had the boot in the first place.
 
My tranny guy said his boot actually touched. I could just fold it under like it was...
 
Folded like that will ruin the boot, 100%. On my cars, I use the long yoke and the seal pictured, there is 1/2", +/- 1/16" visible outside the boot. I have been running them like that on multiple cars for over 40 years, both on street cars and race cars.
 
I suspect it'll wear off some of the end and it'll be fine. I've never seen one burn. I suppose I could trim it a bit...
 
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