Rear differential Oil Q

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My tercel:: 1985 Tercel SR5

Rear differential Oil Q

Post by Hoodwagon » Sat Feb 17, 2018 9:15 pm


So I have a really nice T4 and am trying to keep it nice.

I had a guy swap the rear wheel bearings and front struts. He asked me to bring 4 qts of gear oil do I did. I asked him what he did with it because I assume with that amount he did a drain and fill on the manual trans and front differential.

long story short no, he put 2.5 qts into the rear diff which appears in the FSM to be far too much.

Did it require additional oil because of the bearing service or is it dangerously over full? I have not engaged 4wd since the service.
1985 Toyota Tercel SR5
Pacific Northwest, USA

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My tercel:: '84 Tercel4wd w/extensive mods
Location: Arlington WA USA

Re: Rear differential Oil Q

Post by Petros » Sat Feb 17, 2018 9:25 pm

there is no way you can fit 2.5 qts in the rear diff, there is not enough room even if you over fill it to fill the air space above the fill hole. Likely it would leak out of the vent near the top of the diff housing, or seep out the wheel seals, which should not have any static pressure on them, overfilling it would.

it does not sound like he remembered correctly, or did something else with it.
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)

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My tercel:: Goldie is a 1986 SR5 attualmente con Weber/also owned the first T4WD in STL in late '82
Location: Kirkwood, a 'burb of St. Louis

Re: Rear differential Oil Q

Post by ARCHINSTL » Sat Feb 17, 2018 11:17 pm

To add to Petros' "...or did something else with it." ...
Being a cynic, I would certainly check not only the pumpkin but the trans/diff.
If you are uncomfortable doing it yourself, use another mech.
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