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Help How to tell if I trashed the tranny or the convertor?
After a hard run, upon coming to a stop, while getting under light load I could feel a vibration, later I was nearly home I got on the gas to pass and free spun the motor and heard a whinning like an old school gear drive. It increased and decreased with throttle input and letting off. I stoped at a light and shifted to 1st thinking I lost the 3/4 pack. Nope. I can manually shift from 1st all through 4th. I have all my gears. If I try to take off in d or od it just spins and I hear the dam noise again. Ideas?
Side note. While at the light I gave it some gas while on the brake. Not enough to spin the wheels but just enuff to load it up to see if I have 3/4. This was in Od. While it loaded up I heard AND felt a THUNK, that when I began not being able to leave in D or OD and started hearing the whine.
After a hard run, upon coming to a stop, while getting under light load I could feel a vibration, later I was nearly home I got on the gas to pass and free spun the motor and heard a whinning like an old school gear drive. It increased and decreased with throttle input and letting off. I stoped at a light and shifted to 1st thinking I lost the 3/4 pack. Nope. I can manually shift from 1st all through 4th. I have all my gears. If I try to take off in d or od it just spins and I hear the dam noise again. Ideas?
Side note. While at the light I gave it some gas while on the brake. Not enough to spin the wheels but just enuff to load it up to see if I have 3/4. This was in Od. While it loaded up I heard AND felt a THUNK, that when I began not being able to leave in D or OD and started hearing the whine.
Last edited by foxls1; Apr 16, 2014 at 06:05 AM.
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From: Ann Arbor, MI
The inability to start off in [D3] or [OD] indicates you have broken the forward sprag.
Here is a similar thread in which I give a lot more detail:
https://ls1tech.com/forums/automatic...rking-wtf.html
Unfortunately this means not only a trans rebuild, but the converter will need to sent out for opening and cleaning. Also, any aftermarket cooler needs to be replaced and the stock cooler and lines need to be flushed.
When the trans is rebuilt, you might consider having the Sonnax HD 2-3 HD shift valve installed. Then when you race in [D3], the overrun clutches are always applied which reduce the load on the forward sprag.
If this is the original trans it most likely did not have the "improved BW HD sprag" that became available in later years.
Here is a similar thread in which I give a lot more detail:
https://ls1tech.com/forums/automatic...rking-wtf.html
Unfortunately this means not only a trans rebuild, but the converter will need to sent out for opening and cleaning. Also, any aftermarket cooler needs to be replaced and the stock cooler and lines need to be flushed.
When the trans is rebuilt, you might consider having the Sonnax HD 2-3 HD shift valve installed. Then when you race in [D3], the overrun clutches are always applied which reduce the load on the forward sprag.
If this is the original trans it most likely did not have the "improved BW HD sprag" that became available in later years.
