ISO: Front and/or Rear Differential

Need a car part and don't know where to get it or how to install it. Look here!
Sabrarain97
Newbie
Posts: 19
Joined: Sat Nov 06, 2021 8:11 pm
My tercel:: 1985 Tercel dlx 4WD Wagon Automatic
Location: 97540

Re: ISO: Front and/or Rear Differential

Post by Sabrarain97 »

Okay thank you very much Petros! I will see if we can do any of that, or ask the shop to do it for me when that time comes. Thanks for the advice.
~Sabra w/ a 1985 Toyota Tercel 4WD/FWD Automatic DLX (Terry)
ISO: Working Stock Carb for 3AC Engine
Sabrarain97
Newbie
Posts: 19
Joined: Sat Nov 06, 2021 8:11 pm
My tercel:: 1985 Tercel dlx 4WD Wagon Automatic
Location: 97540

Re: ISO: Front and/or Rear Differential

Post by Sabrarain97 »

Okay thank you very much Petros! I will see if we can do any of that, or ask the shop to do it for me when that time comes. Thanks for the advice.
~Sabra w/ a 1985 Toyota Tercel 4WD/FWD Automatic DLX (Terry)
ISO: Working Stock Carb for 3AC Engine
Sabrarain97
Newbie
Posts: 19
Joined: Sat Nov 06, 2021 8:11 pm
My tercel:: 1985 Tercel dlx 4WD Wagon Automatic
Location: 97540

Re: ISO: Front and/or Rear Differential

Post by Sabrarain97 »

Hi again Petros,

I was just about to do the chalk/tire test. I am wondering if when you are doing this test on a manual, the front and rear are locked, and that’s what makes this work? I feel that in my automatic the front and rear are not connected, so this might only work if I have it popped in 4WD? Are these accurate assumptions? Thanks.
~Sabra w/ a 1985 Toyota Tercel 4WD/FWD Automatic DLX (Terry)
ISO: Working Stock Carb for 3AC Engine
User avatar
NWMO
Highest Ranking Member
Posts: 1644
Joined: Wed May 20, 2015 1:08 pm

Re: ISO: Front and/or Rear Differential

Post by NWMO »

Sabra,

The diffs do not lock. You need to only jack up one side, leaving the other on the pavement and then count the revolutions.

Chris
Psalm 37:4 "Delight yourself in the Lord and he will give you the desires of your heart"

In remembrance of my friend ARCHINSTL:

T4WD augury?
"Oh, do not ask, 'What is it?' Let us go and make our visit."
T.S. Eliot - "The Love Song of J. Alfred Prufrock"

"Now and then we had a hope that, if we lived and were good, God would permit us to be pirates."
Mark Twain
Sabrarain97
Newbie
Posts: 19
Joined: Sat Nov 06, 2021 8:11 pm
My tercel:: 1985 Tercel dlx 4WD Wagon Automatic
Location: 97540

Re: ISO: Front and/or Rear Differential

Post by Sabrarain97 »

So, even with my automatic in neutral this should work? Sorry for being repetitive, I just want to make sure my question is articulated clearly.

Thank you for your help.
~Sabra w/ a 1985 Toyota Tercel 4WD/FWD Automatic DLX (Terry)
ISO: Working Stock Carb for 3AC Engine
User avatar
SirFoxx
Top Notch Member
Posts: 360
Joined: Sun Feb 05, 2017 5:42 pm
My tercel:: 1981 Toyota Tercel w/ 7age

Re: ISO: Front and/or Rear Differential

Post by SirFoxx »

Sabrarain97 wrote: Mon Nov 29, 2021 10:48 am So, even with my automatic in neutral this should work? Sorry for being repetitive, I just want to make sure my question is articulated clearly.

Thank you for your help.
i'm not sure that trick will work with an auto due to the clutch packs n such. You can always try it and see what it does.

My current wagon came with miss-matched diffs. I knew this as when I put it in 4wd while rolling in neutral, the car slowed to a halt as the drivetrain bound up. I ended up pulling the trans and learned the whole trans got replaced with a junkyard special at some point..
Contact me if you need transmission gaskets!
viewtopic.php?t=16285

1988 DLX 4wd Tercel Wagon w/ weber (RIP)
1986 Base 2dr Hatch (RIP / PARTS)
1986 DLX 4wd Tercel Wagon with 7age (RIP)
1985 SR5 4wd Tercel Wagon (RIP)
1985 DLX 2dr Tercel Hatch w/manual 4wd! swap
1982 4dr Tercel (RIP)
1981 2dr Toyota Tercel w/7age (RIP)
1981 3dr hatch Toyota Tercel w/Turbo 4AGE
1981 3dr hatch Toyota Tercel SR-5
User avatar
NWMO
Highest Ranking Member
Posts: 1644
Joined: Wed May 20, 2015 1:08 pm

Re: ISO: Front and/or Rear Differential

Post by NWMO »

Sabrarain97 wrote: Mon Nov 29, 2021 10:48 am So, even with my automatic in neutral this should work? Sorry for being repetitive, I just want to make sure my question is articulated clearly.

Thank you for your help.
I’ve not worked with an automatic, but the principle still applies. When checking the front diff ratio, I would put the trans in 4WD, leave one tire on the ground and place the trans in nuetral. You should then be able to mark your tire and then count driveshaft revolutions required for the tire to make a revolution. With the similar gear ratios, maybe make two tire revolutions and then divide by two. Similar for the rear, but the trans would not need
to be in 4WD.

Chris
Psalm 37:4 "Delight yourself in the Lord and he will give you the desires of your heart"

In remembrance of my friend ARCHINSTL:

T4WD augury?
"Oh, do not ask, 'What is it?' Let us go and make our visit."
T.S. Eliot - "The Love Song of J. Alfred Prufrock"

"Now and then we had a hope that, if we lived and were good, God would permit us to be pirates."
Mark Twain
User avatar
Petros
Highest Ranking Member
Posts: 11935
Joined: Sun Jan 28, 2007 6:31 pm
My tercel:: '84 Tercel4wd w/extensive mods
Location: Arlington WA USA

Re: ISO: Front and/or Rear Differential

Post by Petros »

I am not that familiar with how the auto trans is geared (though I have owned two of them). but it seems to me that when the auto trans is in 4wd, it should lock out the drive train so front and rear are mechanically connected together. these cars do not have a center diff like the modern AWD cars, on the 4wd Tercel, front and rear drive train is locked together when in 4wd. that should not change with the auto trans as far as I know.

it has to be IN 4wd, and the trans in neutral, two wheels on the ground on one side, and two wheels in the air on the other side.
'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)
Post Reply