Rotating the 3rd member in the pumpkin?

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I hope I've got the terminology correct - I understand a lot of people elsewhere in the world call the "crown-wheel-and-pinion" the "third member" - Hence the title I've used.

Anyway I spotted this picture in a 4x4 magazine that I subscribe to over here in NZ:

rotated.jpg

I've since given the magazine away but I think it was an 80 series truck that was featured in the article.

All I ever do with that mag these days is "skim read" the articles and despite skim reading this article twice, I found no reference to anything peculiar about the differential.

Yet the third member appears to have been rotated in order to improve the driveshaft angle. I would have thought this would present problems with achieving effective lubrication (because I would have thought it was desirable to have the pinion teeth at least partially immersed in gear oil all-the-time).

Is the practice of rotating the third member in the pumpkin common? (Or do you think I have misunderstood the photo and it is not rotated at all?)

:cheers:
rotated.jpg
 
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Actually - I haven't been consuming any alcohol --- honest - but this thread/post appears stupid--- surely you CAN'T rotate the 3rd member because you'd never be able to get the axles in. What's going on?
 
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I have seen setups where the diff housing/axle housing has been flipped, and the third rotated 180 degrees relative to the housing to keep it the right way up.. Ive seen SAS conversions with hilux axles flipped to put the pumpkin on the other side, and the third flipped to keep it the right way up.. I've also seen high pinion 80 series Cruisers axles, I think the gears on these are reverse cut too? If the third was flipped without changing anything else, the axles would go in, but wouldnt the wheels want to turn the opposite direction? To flip a third, the housing needs to be clearanced for the crownwheel, and the cover plate flipped too, possible relocation of the filler plug..
 
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What is the story with the 3rd member in the photo? (That's exactly as it appears in the magazine.) It stood out as being unusual to me. (But then I admit I don't go around studying diffs.)

That 3rd member is definitiely on an angle compared to my 40 series diffs. :frown::frown::frown:

:cheers:
 

brew8

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It's centered in the axle not offset to one side is it a hybred ford 9 inch changed out for the toyota housing or something else??? It sure looks like a Toy housing though.
 
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Yet the third member appears to have been rotated in order to improve the driveshaft angle.

My interpretation is that he is simply asking if it is common to rotate the housing a relatively small number of degrees in order to point the pinion more directly toward the transfer case. That is a valid question regardless of what the axle or third member actually is.

The answer is yes, it is very common. It is one of the major steps in a SOA front axle conversion and is often necessary with engine/tranny swaps that result in a very short rear driveshaft. The lubrication issue is addressed by raising the filer plug, thereby raising the lube level as high as the pinion bearing.
 
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My interpretation is that he is simply asking if it is common to rotate the housing a relatively small number of degrees in order to point the pinion more directly toward the transfer case. That is a valid question regardless of what the axle or third member actually is....
The answer is yes, it is very common. It is one of the major steps in a SOA front axle conversion and is often necessary with engine/tranny swaps that result in a very short rear driveshaft. The lubrication issue is addressed by raising the filer plug, thereby raising the lube level as high as the pinion bearing.

Thanks Medusa. But if the housing is rotated, how can the axles (driving the wheels) still fit in? These are pictures of the housing/3rdMembers that I am familiar with:
ARB21.jpg

ARBlocker2.jpg

I can see how they would still fit if you rotated the third member 180 degrees (rotated it upside down) but not for other variations

Still confused:frown::frown:

:cheers:


Oooops. I see what you mean now. No. no. No....... I know that people rotate diff housings about the wheel-axle-centre-line in order to align the pinion centre-line better to the driveshaft. But this is different - It looked to me like the "crown wheel & pinion" had been rotated within the diff pumpkin on an axis perpendiclar to the wheel axle axis (almost in line with the drive-shaft-axis). ....... If you know what I mean. .... s*** this is getting complicated!!!!!!!!!!
ARB21.jpg
ARBlocker2.jpg
 
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It's centered in the axle not offset to one side is it a hybred ford 9 inch changed out for the toyota housing or something else??? It sure looks like a Toy housing though.

Oh OK. Thanks Brew8. I missed reading your post.

So it is some weird non-Toyota (Ford) adaptation to a Toyota housing where the wheel axles still enter horizontally but the pinion is positioned at "wheel-axle level".

I bet that arrangement is weak (prone to failure) compared to Toyota 3rd members!

Anyone got a picture of a "Ford 9 inch" exposing the pinion teeth and crown wheel etc to show me how they accomplish this weird relationship (yet still get the diff to work as a diff should)?

:cheers:
 

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Your alxe in question and a Ford 9"......Which is nothing like what you have pictured.


attachment.php

9ford.jpg
 

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Here is a picture of a 9" designed to run "upside down" from these folks:



Hi9 <---- this is a link




Pic-022.jpg





....and has worked really well in the rear of my junk since March of 2005.


:beer:
 

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I am betting that your pictured axle is Nissan garbage. Find the diaper that this truck was pictured in and report back.



attachment.php

nissan1.jpg
 
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Your second picture in post #9 is from my shop.... ;) (You are welcome).............

Yes. I did pinch that. Thanks Poser.

I've archived those photos (as well as others) to help me when I finally get around to fitting my ARB diff-locks:D

(But the diff locks have sat in my garage for many years now so I wonder when I'll get around to it???)

Thanks

PS. I didn't have the details of who I stole it from to enable me to acknowledge them. ------In future, - I'll try and rename stolen photos in a way that shows me who they originated from. (I should give credit where it's due but I know you're not upset by my lapse here Poser.)
 
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I am betting that your pictured axle is Nissan garbage. Find the diaper that this truck was pictured in and report back....

I'm relying on my memory because I don't have the magazine anymore ------ but.....

The magazine is the May edition (yeah - I know - it has only just turned April here and those of you in far away places are still using March) of "Australian Four Wheel Drive Action". And the vehicle was called "Black Beauty". Nah - More likely "Black Magic". And it was said to be an 80 series cruiser.

Now - Let some Aussi out there tell me how good/bad my memory is.

And perhaps - since this diff is an aussi concoction - they can enlighten us on exactly what it is too? Cos i'm still a very confused person.:crybaby:

If the photo was tampered with - Then it was the magazine that did the tampering (- But then why would they want to annoy their subscribers like that?)

Hey- I hope they don't charge me with a copyright infringement for taking a photo of their magazine photo!!!!:rolleyes:
 

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