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Classic/Antique Car Repair/Transmission Troubles

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Expert: - 5/27/2008


Question
Hi Vern,
I have a 1977 Chevy Nova with a 305 engine and a TH350 transmission. The original transmission was slipping so I removed it and replaced it with a used one from an early 80's GM from a salvage yard. The newer transmission has an electrical plug which I believe has something to do with the torque converter. The salvage yard said this was not important and would not effect the transmission operation if not connected. I installed the transmission it worked fine for a couple of months but now it will not shift out of 1st gear and it always seems to be in first gear even when shifted into park. When in "park" the car will not go forward but it acts like its in gear and the brakes are applied. It seems like the torque converter is always locked up.

Any Suggestions? Thanks, Bill

Answer
Hi Bill:
Any time someone tells you "that wire is not important", don't listen to them. The Chevy 305 and 350 with the TH 350 and later the Turbo 400 trannies, are the best transmission GM has ever built. The sensor wire (that you didn't connect), is the sensor for the tranny over heating, which automatically down shift it into low gear until reset by the sensor relay, which is connected to the ignition. Turning the ignition off and letting the car cool for awhile, will reset it self. Since you don't have that relay switch, you are stuck in low gear.

unfortunately, I don't know how to trick the relay switch into resetting the transmission.If you can find a mechanic to do that, you are good to go until next time.

Classic/Antique Car Repair

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Vern Bullock

Expertise

Visit my website at: http://www.classytransportation.com/ I can answer most questions about autos built in the 60's 70's and 80's. Specifically, Lincolns, Rolls Royces and the Excaliburs. Mechanical issues and technical questions are my expertise. I also have a general knowledge of most older automobiles. Keep in mind, I can only provide answers if the questions are very specific and complete. Without details, I can only speculate and that's not good for solving your problem.

Experience

I have owned and maintained Silver Shadows for over 10 years now. I find most mechanics and even Rolls Royce mechanics have very little knowledge about these automobiles. I have researched these cars in quite a bit of detail and can pretty much tell you what is wrong, if you can describe the behavior in detail. I have saved quite a few RR owners a lot of money and aggravation due to improper diagnosis. I am the owner of Classy Transportation, LLC a luxury limousine service specializing in antique cars, classic cars, vintage cars and exotic cars.

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Classy Transportation, LLC Limousine Service.

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All around the Internet

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I hold a BS degree in computer science and a MS degree in mechanical engineering.

Awards and Honors
I regularly compete at car shows and average around a dozen awards annually.

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See Web site at: http://www.classytransportation.com/

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