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Replacing Drive Shaft with the SR20DET

Started by S12_Lifer · Jun 15, 2016 · 5postsSMF 2010–26

S12_LiferJun 15, 2016, 2:08 pm · #1

Before purchasing a new carrier bearing, I decided to do some research on a one piece Drive Shaft (Aluminum vs Steel).  Since I'm an old guy, my main concern is vibration.  I decided to go with the one piece Aluminum Drive Shaft.  I found a shop near my work and gave them my measurements.  A few days later, the drive shaft was ready for pick up.

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Worn rubber on the carrier bearing which caused me to consider the one piece drive shaft.

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Removing the rear flange from the differential.

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My new one piece aluminum drive shaft.

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Comparing the rear flange.

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I decided since I was in this area to replace the rear transmission seal as well as the transmission mount.

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Here are the part numbers from the items I purchased.

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New seal installed.

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Removing the old mount.

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As you can see, my old mount is worn and needed replacing.

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Removing mount from the cross member.

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On with the new mount.

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Mount and seal replaced.

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I wanted to go with some new bolts so I purchased these.

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Perfect size.

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Bolt fits very well on the new flange.

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In goes the new and much lighter drive shaft.

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Just my luck!  The flange is so thick, I cannot insert the bolt when matched to the differential.  I thought about grinding the bolt but why when I can just use the original bolts, which I did.

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Original bolts fit just fine.

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Refilling the gear oil which was lost when removing the drive shaft.

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As you can see, the 3" drive shaft fits nicely along the tunnel and there is plenty of space for the hand brake cable.

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Close up of the slip yoke which is about 1" exposed.  No concerns there.

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As you can see, the rear flange fits nicely on the differential. 

Once starting, I noticed a slight vibration during idling.  The Nismo mount is suppose to be 20-30 percent stiffer. Nothing really major.  Acceleration was instant and smooth.  I did notice more vibration when driving anywhere from 70-90 mph.  I'm going to give this drive shaft a month or so of testing and decided to go with it or to convert back to the two-piece (with a new carrier bearing).

weitrhinoJun 15, 2016, 9:30 pm · #2

Nice work. Just out of curiosity can you ballpark the figure on having that new shaft made?

S12_LiferJun 15, 2016, 11:51 pm · #3

$400-450 with a one year warranty.   He does offer military discount so let me know if your interested. My wifes S12 has a one piece steel drive shaft which cost me about $300 a number of years ago.  She has the CA20e and has no vibration what so ever.

sideways_s12Jun 18, 2016, 8:33 pm · #4

Nice work! I figured the nismo mount might cause a little vibration from stiffness. Is it bad at those speeds or would you consider it tolerable?

S12_LiferJun 20, 2016, 1:27 am · #5

I am still noticing vibration while driving 65-90 mph.  The vibration is tolerable but, if your into a smooth comfortable ride like me, it can be annoying.  I'm only driving at these speeds for about 10-15 minutes (to and from work).  I can't imagine driving to Vegas or Arizona with the vibration.  I am seriously thinking about going back to the two piece.  This Aluminum shaft should be the same measurements if you have a KA or even the CA.  I may place this shaft on the "Want to buy" link.