Transmission problem TH350
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Transmission problem TH350
I had my exhaust welded up yesterday. The problem is now when the car is in drive (D) it will not shift into second no matter how fast or how high the RPM's are. Also If I start out in 1 and manually shift it it works fine. Also at times it will act like its in nutural untill I get the RPM's up to around 3k or better. That part is kind of rare however.
I'm thinking my exhaust guy somehow managed to get the rubber vacuum line to close to the new exhaust pipes. I havent had a chance to check though. It ran fine on the way home from the shop. Roughly 35 miles. I'm going to try and find time tomorrow to check the vacuum line. Any thoughts in the meantime?
ps: The fluid is full. I did recently change the filter and fluid.
Here's a bad pic of the car from the shop yesterday
I'm thinking my exhaust guy somehow managed to get the rubber vacuum line to close to the new exhaust pipes. I havent had a chance to check though. It ran fine on the way home from the shop. Roughly 35 miles. I'm going to try and find time tomorrow to check the vacuum line. Any thoughts in the meantime?
ps: The fluid is full. I did recently change the filter and fluid.
Here's a bad pic of the car from the shop yesterday
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I agree on the vacuum line. Could that cause the car to act like it's in nutural as well. I had a car in the past develope a vacuum leak that caused to to shift in high RPM's. I never had the other issue though.
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I'm going to crawl under there tomorrow. I'll update after I check it out. I hate when posters don't give me closure lol
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From: BC
Yes on the vacuum line. If you were to go out and put your foot to the floor and let it go as high as it will go eventually it will shift. It is acting as if you have wot and vacuum has dropped to 0.
As to the sensation of going into neutral, when a th350 is in D, in 1st and second gear the holding is done through a one way clutch so when you let off the pedal the sprag just freewheels in the opposite direction. You have no engine braking. In selected 1st or selected 2nd there is a band holding in addition to the sprag clutch and you get engine braking when you back off the throttle.
It's one of the things that in my mind makes the th350 such a nice shifting trans. There is no element (clutch or band) that has to be released for an upshift, only the apply of another clutch. On Ford and Chrysler transmissions of that era the 1-2 shift was the same, but to go from 2-3 the release of the frt band has to be timed perfectly with the application of the direct clutch.
There, more than you wanted to know about your transmission.
Steve g
As to the sensation of going into neutral, when a th350 is in D, in 1st and second gear the holding is done through a one way clutch so when you let off the pedal the sprag just freewheels in the opposite direction. You have no engine braking. In selected 1st or selected 2nd there is a band holding in addition to the sprag clutch and you get engine braking when you back off the throttle.
It's one of the things that in my mind makes the th350 such a nice shifting trans. There is no element (clutch or band) that has to be released for an upshift, only the apply of another clutch. On Ford and Chrysler transmissions of that era the 1-2 shift was the same, but to go from 2-3 the release of the frt band has to be timed perfectly with the application of the direct clutch.
There, more than you wanted to know about your transmission.
Steve g
