Fixing Oil leak from the Side of Front Diff

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J Dumarais
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Posts: 49
Joined: Mon May 11, 2015 10:33 am
My tercel:: Toyota Tercel 4WD Wagon '86 & Jose 87' Tercel 4WD Wagon

Fixing Oil leak from the Side of Front Diff

Post by J Dumarais »

My 86' was leaking from the CV axle plug for a wilde now and i Finaly open it to see what was going on in there, after changing oil seal with no result.
Everythink look healthy in there, carrier bearing, gear, etc. But there almost 1.5mm play beteen one of the side gear and housing. Could it make bolth side leak anyway? my book they talk about thicker washer...
I hav'nt locate any inside parts for the diff yet in Bc.
Looking for a pumking also, use or new...nothing yet
I'm looking to know mostly what the best think to fix in there, would the perfect washer would fix it, or i Will have to pull the tranny out again in à couple of month.
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Petros
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My tercel:: '84 Tercel4wd w/extensive mods
Location: Arlington WA USA

Re: Fixing Oil leak from the Side of Front Diff

Post by Petros »

there was a lot of play in the diff assembly? and the bearing was not bad? the lash between the ring and pinion gears is very critical, traditionally this clearnace was adjusted with shims at the base of the pinion gear, and at each side of the diff assembly. you adjust the pininon in and out, and the diff left and right, until you get the correct contact on the gear tooth face, and the correct clearance.

Like a lot of production cars toyota used soft crushable washers to set the lash faster in assembly, but this is not suitable for repair, and I have been told they loosen up after several hundred thousand miles. Which means the lash has to be reset, which may be the case with you.

There are a few specialized shops around that do nothing but set the lash on differential assemblies, some even that specilze on Toyotas (mostly to install LSD diffs in the 4x4 toys). you might see if you can find one of those and have them take care of it for you.

the other viable alternative is to find a good used front diff assembly and swap out the whole thing. You can buy the shims on-line to correct the lash in your front diff yourself. But I would advise against it unless you have done this kind of work before. If it is off, it will eventually brake off gear teeth because of improper loading, and it could trash the whole transmission.

what year is your Tercel? there are different different ratios for '83-84 Tercel4wd, and for '85 and later, and also different for auto trans and manual transmission. there might be someone on the forum with an extra front diff assembly for your car.
'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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J Dumarais
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Posts: 49
Joined: Mon May 11, 2015 10:33 am
My tercel:: Toyota Tercel 4WD Wagon '86 & Jose 87' Tercel 4WD Wagon

Re: Fixing Oil leak from the Side of Front Diff

Post by J Dumarais »

My car is an 86' with a 87' manual 6speed tranny. There only the driver side side gear that wiggle, i guess the three other are whorn out a bit but everything feel Nice and smooth.
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Petros
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My tercel:: '84 Tercel4wd w/extensive mods
Location: Arlington WA USA

Re: Fixing Oil leak from the Side of Front Diff

Post by Petros »

drivers side gear? the small spider gear in the center of the diff? or do you mean the big ring gear?

if the spider gear is buggered up, likely the adjoining parts it mates with are also damaged. sounds like you should replace the whole assembly.
'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)
User avatar
J Dumarais
Member
Posts: 49
Joined: Mon May 11, 2015 10:33 am
My tercel:: Toyota Tercel 4WD Wagon '86 & Jose 87' Tercel 4WD Wagon

Re: Fixing Oil leak from the Side of Front Diff

Post by J Dumarais »

Not the ring gear, she's Old but she can go on. The gear where the CV axle slide in. There a washer with some hole in it that is beteen the pumking housing. He's the only one in there with a play.
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