Oil seal mod. for 3053 input shaft

[brianp454]

As I’ve looked into this, I’ve found that there are at least two versions of this part out there (note the thick flange version has obviously deeper counterbores):


1) Thicker mounting flange with more material on the convex side and less material on the concave side
2) Thinner mounting flange with less material on the convex side and more material on the concave side




I measured 11 OEM parts yesterday and found them all to be within +/- 0.002 inch or less on any critical dimension. An in fact, they were all right on the money and completely inconsistent with gringels claims. There's absolutely noting more that can be done past 100% measuring every part and confirming they are correct. For all intents and purposes they are functionally equivalent. End of story.

Regardless, the seal as I’ve worked it out results in no loss of strength of the part. I base this on the models of the parts and applying loads in an FEA model and demonstrating that the part with the machined pocket results in no lack of strength over the original part. If the modified part has the same strength of the unmodified part how can anyone claim that the part is weak?

 

[gringeltaube]

I base this on the models of the parts....

With all respect: that's the problem; your "model" is just wrong: it shows 87.5mm where in reality we have 88.9mm (3.50"). So instead of 2.5mm material left it really is only 1.1mm (in the best case).

.....how can anyone claim that the part is weak?

It's just common sense; if you actually measured that part you will come to that same conclusion.

To be clear: that modified bearing retainer is now extremely fragile but I'm not saying it won't work: 1) Once the transmission was installed and everything in normal operating condition, the forces applied radially to the shaft portion are minimal.
2) In the event of the nose snapping off it really can't go very far and/or do any collateral damage. The input shaft would still keep it centered and the distance to shift forward is only about 4mm, before it touches the clutch disk hub.
But... this means returning home soon and pulling the whole transmission out again!




G.

 

[Jeepsinker]

Brian, I don't want to be a smarta$$, but computer models have led to some huge man made disasters...

 

[rustystud]

We do need to figure this out before anyone installs it. I don't want to be stuck in Alaska with a broken transmission !

 

[brianp454]

Here's a picture from under my truck this morning. I used to have a little dribble of oil on the drive from every stop, now, NOTHING!



Rusty, When are you available for me to drive up so you can drive my truck with this installed? I'm hoping to put a stop to this nonsense.

 

[Tow4]

Just machine a sample and cut it in half if you can't settle the argument using a model and measuring. A physical sample of the end product will answer all the questions.

 

[brianp454]

https://youtu.be/1Gvdl9VNIoo

 

[brianp454]

If I do will you buy one?

Just machine a sample and cut it in half if you can't settle the argument using a model and measuring. A physical sample of the end product will answer all the questions.

 

[doghead]

Let's not turn this thread into an ad!

 

[Jeepsinker]

Hey guys, been away for a while now. I've been having a lot of life problems these past few months. I apologize to all of you who have been patiently waiting for news on getting some of these manufactured and shipped. This is why I'm glad I didn't collect any money from anyone before getting some of these made. You guys would have been pissed. Anyway, my machinist seems to be perpetually behind the curve because he has so much work. I'm trying to get some of my own money together to at least get a couple made and shipped, because of course if I pay first, I can probably get them made more quickly.
Note: I've got close to 20k miles on mine now and it has started leaking. Upon inspection it turned out to be that the seal has failed, or begun to fail. I used a single lip seal from Napa when I put it together because I was rushing to get the truck ready for last year's rally. In light of the seal failure, it is mandatory that a quality double lip seal be used.
Don't give up on me guys. I always make good on my word. Life has just put me through the wringer for quite a while now.

 

[m-35tom]

i am still not sure why anyone would want to do this? the original does not leak, it does not even seep, there will be no oil on the floor, ever, if it is all put together as design intended. if you anticipate driving in deep water a fording kit is still a better option as it will keep both the clutch and trans dry. and to those who will say that the front of their trans leaks? it is because something is wrong.

 

[gringeltaube]

Tom, I used to think exactly the same way... And I fully agree with you that if it leaks while the input shaft is spinning, then something isn't right.

But... I have seen this even with all-new transmissions, running on the bench: every time after a stop - a few hours later I had oil that came out, just a couple drops, then it stopped. This may not be detected when in service - with the TO-bearing & -carrier in place, but it happens...
No oil on the floor doesn't mean no-oil slowly collecting in the bell-housing (and eventually getting on the clutch disk)

Usage; operating temps; type/brand of lubricant... certainly many variables that can play in favor or against.
For some reason the later transmissions all came with a seal.

Also, someone please explain to me why the big brother, the 5-ton Spicer #6453 has a seal there? The basic design is the very same, only everything doubles the size of the #3053.



G.

 

[silverstate55]

Brian, I don't want to be a smarta$$, but computer models have led to some huge man made disasters...

LOL, that is awesomely funny!!! Good one!!

 

[rustystud]

Tom, I used to think exactly the same way... And I fully agree with you that if it leaks while the input shaft is spinning, then something isn't right.

But... I have seen this even with all-new transmissions, running on the bench: every time after a stop - a few hours later I had oil that came out, just a couple drops, then it stopped. This may not be detected when in service - with the TO-bearing & -carrier in place, but it happens...
No oil on the floor doesn't mean no-oil slowly collecting in the bell-housing (and eventually getting on the clutch disk)

Usage; operating temps; type/brand of lubricant... certainly many variables that can play in favor or against.
For some reason the later transmissions all came with a seal.

Also, someone please explain to me why the big brother, the 5-ton Spicer #6453 has a seal there? The basic design is the very same, only everything doubles the size of the #3053.



G.

Gerhard, you mentioned that the later Spicer 3053 transmission used a front oil seal. Do you know what years this would be ?
Thanks.

 

[gringeltaube]

Did I say that...?
No, I was referring to later, more recent transmissions, in general (like this one described here, for example...)
Our good-old Spicers (#3052/3053) have never seen any changes, in all these years.

 

[rustystud]

Did I say that...?
No, I was referring to later, more recent transmissions, in general (like this one described here, for example...)
Our good-old Spicers (#3052/3053) have never seen any changes, in all these years.

I must have misread your post. Too bad, that would be nice and easy to just get a later model housing.

 

[rustystud]

Hey Brian, have you cut one of your modified input housings to see if there is enough material there yet ? I was hoping you would do that so we could all see and put this question to rest.
Then we can start buying your input housings !

 

[steve6x6x6]

Gerhard and I talked about this at the GA. rally. This is what i have at this moment. 100% welded to the ID bore, to be fully machined out by next week end. Who is on board?

 

[JasonS]

The SM420 was eventually fitted with a neoprene seal to reduce leaks. Novak offers a service/ kit to add one to the earlier versions. https://www.novak-adapt.com/catalog/transmission/transmission-parts/sm420-parts/

 

[rustystud]

The SM420 was eventually fitted with a neoprene seal to reduce leaks. Novak offers a service/ kit to add one to the earlier versions. https://www.novak-adapt.com/catalog/transmission/transmission-parts/sm420-parts/

That's a pretty cool idea and at only $178.00 a great deal ! I wonder if they can build our housings and grind our shafts for that price ? Think I'll call them tomorrow.