Transmission damage; how bad is it?

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FranklinTheWagon
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My tercel:: 1983 Toyota Tercel 4WD Wagon

Transmission damage; how bad is it?

Post by FranklinTheWagon » Fri Dec 20, 2019 8:29 am

I've had a rough run with my poor Tercel: Franklin. After a few breakdowns and long bouts of troubleshooting, it was finally running really well. I went camping two days ago and he performed marvelously for 99% of the drive. At some point on the journey either a rock bounced up on the gravel road and hit my transmission, or my main seal blew. Either way, the tranny fluid pretty quickly leaked out without my knowing and I made it 279/280 miles when, pulling away from a light, I heard a crack, lost power to the wheels in all gears, and barely limped it out of the intersection in 4wd before towing the car the last mile home.

Problem:
No power to wheels in any gear (reverse included) in 2wd.
Letting off the clutch in gear makes a horrible grinding noise
In 4wd the car will move but I only went about 30 feet to get to
safety before stopping for fear of further damage.
When I got under the car at the gas station where I stopped, I
could see tranny fluid pouring out in a constant stream. There
was only maybe a quart left to pour out before it was totally
empty.
Both CV axles look to be unharmed from a first look.
The car can be pushed in any gear as though in neutral
Transmission had no issues or worries prior to this.

My first guesses are a torn CV spline or a shattered input shaft/bearing. Would these be the most likely candidates?

Also, if this is the problem and I can get it swapped out myself, is it likely that no other damage occured or is widespread failure more likely? I have no prior experience with transmission work apart from a fluid change.

Lastly, what can I do about a torn input bearing/shaft? Is that a readily available part?

Thank you

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NWMO
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Re: Transmission damage; how bad is it?

Post by NWMO » Fri Dec 20, 2019 10:09 am

Franklin,

Correct terminology helps folks, though your post adequately conveys your issue. The term transmission fluid is generally reserved for automatic transmissions, whereas the manual transmissions hold gear oil. From your description, you lost the transmission/front diff gear oil on your drive home and had a catastrophic failure. If 4WD still provides motion, it shouldn't be an input shaft/clutch problem. It sounds much more likely that one of the front axles broke OR the front diff "crunched". If the front diff took a huge poop, I would expect one of the front tires to be locked up. So if you can push it etc., hopefully the grinding you are hearing is the two ends of one of the axles (broken) spinning against one another. You need to get it up in the air and figure out which axle is the likely problem and see if you can get it removed (I would recommend removing/inspecting both axles). You may find twisted splines that make it a bear to pull axles (particularly if you are pulling the last piece of a broken axle).

Chris

If you are actually referring to the transmission input shaft, I would expect the engine may have to come out for renewal.
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teranfirbt
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My tercel:: '86 SR5 4WD, 5AFE, lifted rear, 195/70/14 tires
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Re: Transmission damage; how bad is it?

Post by teranfirbt » Fri Dec 20, 2019 11:26 am

Without performing a full teardown it will be difficult to assess the condition of the transmission internals. The first thing I would do is remove the cover from the front differential and see if the ring and pinion are in tact. Since the car moves in 4wd it is most likely a problem with the front differential.

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Petros
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My tercel:: '84 Tercel4wd w/extensive mods
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Re: Transmission damage; how bad is it?

Post by Petros » Sat Dec 21, 2019 2:29 pm

sorry to hear about your trouble. Most likely you had a leaky seals that caused the loss of gear oil. it would be very rare to crack the diff or trans case.

either way, the trans has to come out and be torn down. You might get lucky and find that it is a sheared off CV axle stub (so check that first, including taking off the front cover as Teranfirbt suggests). if you have any trashed internal parts, you have to pull the whole trans and front diff/bell housing anyway. Without getting it out there is no way of knowing what if anything can be salvaged. even if confined to the front diff or forward output shaft, you have to clean out all the broken parts and metal particles really well or it will trash the rest of the transmission. there are passages from the front diff to the main gear box and transfer case to share the lubrication between them, so you have to clean it all out with solvents several times to get all of the old gunk and metal shavings out.

Likely you will just need to swap out the whole trans axles assembly, so start looking for one now (it may be hard to locate one, but you may get lucky). you may be able to just replace the front diff input shaft or one of the cv axles, but you will need verify that before you try to fix it.

Good luck.
'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)
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xirdneh
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Re: Transmission damage; how bad is it?

Post by xirdneh » Sat Dec 28, 2019 6:05 pm

losing the oil and driving causes the tranny to over heat. most likely teeth on main drive gears melted or broke off. with only a QT in tranny thats not enough. when you remove the tranny and find those symptoms it will not be fixable. should be able to salvage the synchros and thats about it
Love those Tercell 4x4 wagons but they sure suffer from road noise.

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