Transmission question
Thread Starter
Racer
Joined: Aug 2011
Posts: 455
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From: Lewes Delaware
Transmission question
Ok, newby question here. Been looking at used C3's and I see a common thread in a lot of the descriptions. Transmission replaced or transmission rebuilt. Some of these cars are in the 50K miles range. Why are these trannys being rebuilt or replaced with so few miles? I also see the same thing, although not as often, with motors.
Team Owner
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From: Southbound
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From: BC
Ok, newby question here. Been looking at used C3's and I see a common thread in a lot of the descriptions. Transmission replaced or transmission rebuilt. Some of these cars are in the 50K miles range. Why are these trannys being rebuilt or replaced with so few miles? I also see the same thing, although not as often, with motors.
In all my years of doing transmissions I don't think I ever saw one "worn out" to the point of failure. The ones that have a lot of miles on them when the seals finally let go may have some worn bushings and washers, but never to the extent that they would cause it to stop working.
Steve g
Thread Starter
Racer
Joined: Aug 2011
Posts: 455
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From: Lewes Delaware
If you are referring to automatic transmissions, it is because they don't fail as a result of worn out parts. It's a function of time, not miles. They experience internal seal failures, which then result in clutch failures. There are rubber o-ring and lip seals thruout an automatic. As the rubber ages it gets hard and brittle. That happens whether it is sitting on a shelf or in the transmission. Once the lip of the seals breaks off (very common on th350's) or the oil is bypassing a hard shrunken o-ring the clutch apply pressure is reduced and the initial engagement is slow. Trying to move the car before the clutch fully engages takes the linings off the clutch.
In all my years of doing transmissions I don't think I ever saw one "worn out" to the point of failure. The ones that have a lot of miles on them when the seals finally let go may have some worn bushings and washers, but never to the extent that they would cause it to stop working.
Steve g
In all my years of doing transmissions I don't think I ever saw one "worn out" to the point of failure. The ones that have a lot of miles on them when the seals finally let go may have some worn bushings and washers, but never to the extent that they would cause it to stop working.
Steve g
Thank you Steve. That makes perfect sense.
Safety Car
Joined: Sep 2005
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From: Southeast, Tennessee
St. Jude Donor '09 thru '26
with a 5 digit odometer, the chances are virtually 100% that you can add the 100k to the number. unless you come upon a fully documented vehicle, you have to assume that the "clock" has been around once at least.
Drifting
Joined: Apr 2003
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From: Johnson City TN
My original TH350 was still working fine after about 110k.
But I got a really good deal on a 700R4, so I jumped at the chance to switch to overdrive.
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Thread Starter
Racer
Joined: Aug 2011
Posts: 455
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From: Lewes Delaware
I was wondering why some of these cars I was looking at looked so worn and beaten with so few miles. I know my pickup has around 70K and still looks great. This makes sense. So, one would probably want a C3 that had a new tranny and engine unless collecting as a numbers matching car. Good stuff on here...I luv it! Thanks guys!
Burning Brakes
Joined: Jun 2006
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From: South Dakota
It's not the mileage as much as the time and abuse of non use.
Le Mans Master
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From: Tampa Florida
1971 that I've owned for 36 years.
Safety Car
Joined: Sep 2005
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From: Southeast, Tennessee
St. Jude Donor '09 thru '26
71 green. didn't mean to be insulting, lol. i stated "virtually", lol. you can substantiate your. you have owned it most of it's life and had bought it when it was only a couple of years old. i'm sure it is a beautiful automobile and certainly one most of us would love to have in our own garages. most can't say that and for the most part, most have changed hands a lot more often than yours i would think. obviously nothing is 100%, but you have to assume without documentation the chances of a low mileage car in somewhat rough condition will have either been mistreated in life or storage or isn't what the "clock" reads.