T10-1C Help
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T10-1C Help
I have an aluminum T10 transmission with T10-1C on the main case with a date code of H-7-61 (Aug 7 1961). The main case has no bowtie emblem. The side cover is dated 6-19-63. The tail shaft housing is dated 5-21-63. It is a T10-7C tail housing (no bowties). I can not find any reference to T10-7C tail shaft housings. It is 10 spline input with no grooves. Stamped on the main case is WJ2812 and 2100989.
My question is what is this transmission? Is it pieced together from other transmissions or could the T10-1C case from 61 have be paired with the other 63 dated parts at the factory? I was told this is a Corvette or 409 impala trans. Any ideas? Anybody know what the 7C tail shaft housing is?
My question is what is this transmission? Is it pieced together from other transmissions or could the T10-1C case from 61 have be paired with the other 63 dated parts at the factory? I was told this is a Corvette or 409 impala trans. Any ideas? Anybody know what the 7C tail shaft housing is?
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I'm thinking it is either an over the counter service replacement, OR, a put together T-10 (more likely).
From what I have observed through the years the addition of a Bowtie on the case came along about Jan-Feb 62.
In FULL SIZE cars, the T-10 was replaced with the Muncie about Feb 63. The Corvettes switched to the Muncie about Mar 63.
Thus, any date after Mar-Apr 63----------------------MOST LIKELY--------------------did not come out of a production car.
If the transmission is out of the car, use black Magic Marker and mark one input spline and one output spline. Put it in 1st gear. Rotate the input and count how many times the output turns. It will only be a 2.20 or 2.56.
From what I have observed through the years the addition of a Bowtie on the case came along about Jan-Feb 62.
In FULL SIZE cars, the T-10 was replaced with the Muncie about Feb 63. The Corvettes switched to the Muncie about Mar 63.
Thus, any date after Mar-Apr 63----------------------MOST LIKELY--------------------did not come out of a production car.
If the transmission is out of the car, use black Magic Marker and mark one input spline and one output spline. Put it in 1st gear. Rotate the input and count how many times the output turns. It will only be a 2.20 or 2.56.
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Navigator
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Thanks for the info. I never considered the over the counter replacement possibility. It probably is more likely pieced together though.
Any Idea on the 7C tail shaft case? I can't find any info at all on that.
Any Idea on the 7C tail shaft case? I can't find any info at all on that.
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From: Mustang OK
2026 Corvette of the Year Finalist - Modified
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I've only seen T10-7, T10-7A. T10-7B, T10-7D.
At this time the only T10 tail housing i have on the shelf is a T10-7D dated Dec 62.
Melting Slicks
Joined: Jul 2004
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From: Maryland
The main case is from a 62 Corvette as the partial VIN next to the assembly date is the 989 car off the line. The tailshaft and side cover are 63 replacment parts.
Last edited by Donald #31176; Aug 15, 2023 at 01:36 PM.
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Thread Starter
Navigator
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One more question, is there something in the partial VIN that lets you know "from Corvette" or just going based off of all T10s in 61-62 were iron unless in Corvette or 409 cars? Did some lower HP output 327's in Corvettes have iron cases?
Le Mans Master
Joined: May 2005
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From: Central Maryland
Am I mistaken in thinking that J=September? Was the letter "I" skipped (not used) in the month code sequence?
Co-incidentally, the non-original T-10 in my '63 has main case markings H17-1, which I believe is only ten days after the OP's unit (Aug 17, 1961), and it is a T10-1B main case and tailshaft.
Live well,
SJW
Co-incidentally, the non-original T-10 in my '63 has main case markings H17-1, which I believe is only ten days after the OP's unit (Aug 17, 1961), and it is a T10-1B main case and tailshaft.
Live well,
SJW
Thread Starter
Navigator
Joined: Aug 2023
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Am I mistaken in thinking that J=September? Was the letter "I" skipped (not used) in the month code sequence?
Co-incidentally, the non-original T-10 in my '63 has main case markings H17-1, which I believe is only ten days after the OP's unit (Aug 17, 1961), and it is a T10-1B main case and tailshaft.
Live well,
SJW
Co-incidentally, the non-original T-10 in my '63 has main case markings H17-1, which I believe is only ten days after the OP's unit (Aug 17, 1961), and it is a T10-1B main case and tailshaft.
Live well,
SJW
Melting Slicks
Joined: Jul 2004
Posts: 2,869
Likes: 196
From: Maryland
Your are correct as I forgot about the letter I. It makes sense since car 989 was built on or about Oct 5. Up till about 11/60 the T10 main cases were cast iron in Corvettes.. Thereafter the main cases were aluminum.
Last edited by Donald #31176; Aug 15, 2023 at 07:00 PM.
Le Mans Master
Joined: May 2005
Posts: 7,373
Likes: 2,288
From: Central Maryland
Le Mans Master
Joined: May 2005
Posts: 7,373
Likes: 2,288
From: Central Maryland
Thanks for the kind words. It is, and will remain, a driver and a mongrel -- and a never-ending work in progress. But, yes, it is a joy to drive. It was painted around four years ago. Plenty more remains to be done.
Live well,
SJW
Live well,
SJW
Thread Starter
Navigator
Joined: Aug 2023
Posts: 9
Likes: 0
I'm thinking it is either an over the counter service replacement, OR, a put together T-10 (more likely).
From what I have observed through the years the addition of a Bowtie on the case came along about Jan-Feb 62.
In FULL SIZE cars, the T-10 was replaced with the Muncie about Feb 63. The Corvettes switched to the Muncie about Mar 63.
Thus, any date after Mar-Apr 63----------------------MOST LIKELY--------------------did not come out of a production car.
If the transmission is out of the car, use black Magic Marker and mark one input spline and one output spline. Put it in 1st gear. Rotate the input and count how many times the output turns. It will only be a 2.20 or 2.56.
From what I have observed through the years the addition of a Bowtie on the case came along about Jan-Feb 62.
In FULL SIZE cars, the T-10 was replaced with the Muncie about Feb 63. The Corvettes switched to the Muncie about Mar 63.
Thus, any date after Mar-Apr 63----------------------MOST LIKELY--------------------did not come out of a production car.
If the transmission is out of the car, use black Magic Marker and mark one input spline and one output spline. Put it in 1st gear. Rotate the input and count how many times the output turns. It will only be a 2.20 or 2.56.