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The Agony Of A Rear Gear Fluid Change

Seventy6er

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So I just serviced my rear Diff (on 76), which was a contortionist's Hell.

I may be "pleasantly on the heavy side" (so the doctor says), or I'm just feeling my old and rusty bones, but for the Love of God, how does anyone get passed all the obstructions facing the diff cover for removal and reinstallation?!

YES, I finally managed after regrouping from frustration and got'r done after two days, and maybe I should've just asked y'all for advice beforehand, but does anyone have any tricks for the next time?

I'm still feeling the pain in my neck (literally) and otherwise walking around with a twitch in my eye :)

GM10Bolt.jpg
 
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WesleyW

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I feel your pain.

I’m 62, in relatively good shape, and replaced the differential fluid plus upgraded to a Moser cover.

After everything is back together, including reinstalling the rear stabilizer bar, the cover leaks.

I’ll get back to it one of these days.

Edit to add: Man, that fluid stunk! It’s been months, and I still remember the smell.
 

Seventy6er

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You went further than I did.

I "thought" (briefly, LOL) about removing the bar but, for some reason did it the very hard way.

I used a Fel-Pro gasket on mine, dry as intended, despite half of its reviews suggesting issues with leaking.

Anyways, I just got back home after running mine around the area a little bit to test for leaks, and so far, so good, but more time will tell.

BTW, I torqued the bolts to 25 Lb/Ft and couldn't find info if lower (or higher) numbers were recommended.

Thanks, and next time I'll have to take additional steps by removing the bar (ugh).
 

TOG

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I was about to change the diff fluid in the '73 Fire Am due to an increasingly loud whine on decel.

After some research, I found that a loose input shaft nut could cause this.

Sure enough, it was not even finger-tight.

Re-torqued it, and the whine is gone, as is a leak.

I should change the fluid anyway, and it's been in there for 30+ years from when the diff was replaced after the spider gears grenaded, maybe over the winter.
 

86 Silverbird

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When you go to change the differential fluid, use a Vac-extract to suck the gear oil out of the fill hole.

It saves a lot of cleanup.

Once the gasket surface is cleaned up, I use a couple of studs in two top holes and then hang the gasket and differential cover on the studs before inserting the rest of the bolts.

It makes replacing the cover so much easier.

Amount of oil removed from dipstick tube only (2)a.jpg