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Differential Weight Orientation?

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QQ: For the Differential Skid Plate / Weight that attaches to the Front Differential mount, does the thicker end on the left hand side of the photo face rear-ward or forward. I have it oriented with the left hand side facing rear-ward, but I am getting a little clunking when shifting. 

 

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In my experience clunking when shifting is a diff mount insulator that’s past it’s best. Basically, the nose of the diff lifts when you accelerate, then when you cut the power with the clutch mid shift, the diff “falls” backdown and clunks if the rubber has let go or gone soft. On mine I found that it looked perfect but was completely dead when I took it off. The worst scenario I had a few times was changing up at 6.5k rpm and hearing a very LOUD BANG + feeling a momentary deceleration like touching the brakes - as the input flange kissed the ARB!!!!! [emoji33][emoji33][emoji33]

 

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  • 3 weeks later...
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@AK260 Checked the front diff mount, but it was basically new (at least in appearance) so I kept looking. Traced back the issue and have found the source of my noise. I installed new poly bushings and had tightened my control arm bushing retainer bolts, but had not torqued them because the service manual recommends doing it on the ground. Long story short, forgot to torque the inside ones before my test drive so there was a little play. Torqued them to 105 ft/lbs and its cut down the nose significantly.  

[mention=32052]AK260[/mention] Checked the front diff mount, but it was basically new (at least in appearance) so I kept looking. Traced back the issue and have found the source of my noise. I installed new poly bushings and had tightened my control arm bushing retainer bolts, but had not torqued them because the service manual recommends doing it on the ground. Long story short, forgot to torque the inside ones before my test drive so there was a little play. Torqued them to 105 ft/lbs and its cut down the nose significantly.  


Well done! At least you found it. I tend to mark the important load bearing bolts / nuts with a little bit of acrylic yellow (airfix model) paint. That way I know if the critters have moved at all. This sort of thing worries me a lot given my very spirited driving.
S
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Well done! At least you found it. I tend to mark the important load bearing bolts / nuts with a little bit of acrylic yellow (airfix model) paint. That way I know if the critters have moved at all. This sort of thing worries me a lot given my very spirited driving.
Yeah, I have an orange paint pen for this. Marked the rear ones, but couldn't see if i had marked the front ones because of the sway bar.

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  • Author
Here's something for anyone finding the original question.  These cars are full of clunking and thumping possibilities.
https://bringatrailer.com/listing/1976-datsun-280z-38/
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Thanks Zed! Good to know it's the right way haha

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