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Just bought this 56. It ALWAYS shifts hard from 1-2. Chirps tires hard. Also shifts real hard from 1-2. All the other gears are fine. TV cable was replaced and set where it needs to be. Mechanic said it could have a corvette servo in it. All I know its really annoying chirp tires every time and can't be good for it.

So what do you think?

By the way, its great to be back on the forum!!
 

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Some shift kits (B&M is one) have the option of deleting the servo spring as a way of firming up the shift. Often that mod goes too far. Another way of firming up the 1-2 shift is the big diameter Corvette servo. Combined with deleting the spring, you get a very harsh shift.
 

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Mine does the same thing and yes it has the Corvette servo in it, I just kinda of ease it into 2nd then you can hammer on it. The 1st to 2nd shift is the only one that seems real hard
 

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Like the guys are saying, the trans has a shift kit in it. Probably installed when/if it was rebuilt by a previous owner. Without the stock parts you will have to have a trans shop work on it to soften the shifts.
Mark
 

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If it shifts at the right spot, just hard, it is the servo not the governor. Most likely like others said, a Hi Po / Corvette servo was installed. If you really hate it, go back to a stock servo. You will have a much softer shift.
 

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If it shifts at the right spot, just hard, it is the servo not the governor. Most likely like others said, a Hi Po / Corvette servo was installed. If you really hate it, go back to a stock servo. You will have a much softer shift.
I'm experiencing the same thing, can someone recommend a milder shift kit that will eliminate the jolt from 1st to 2nd gear, back in the day I enjoyed punching it off the line but as I've gotten older my car has become more of a cruiser. Just want my transmission to shift smoothly without having to gun it all the time, thanks!
 

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The separator plate may been drilled out too large or a accumulator spring left out usually the shift kits have a min & max drill size to enlarge the separator plate most chose the max drill bit but likely as mentioned the corvette servo has been installed.Or a combination of the above.
 

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Get a new shift kit and a new separator plate and follow the instructions. A Corvette servo is not that harsh unless some other things are done. You may also need to source things like stock servo springs.
 

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Get a new shift kit and a new separator plate and follow the instructions. A Corvette servo is not that harsh unless some other things are done. You may also need to source things like stock servo springs.
Can you by chance recommend a shift kit and a separator plate considering my circumstance? I called Summit and tried to explain it to them, but they said they only carry high performance shift kits. I'm good with high performance as long as the car shifts smoothly, currently shifts really hard from 1st to 2nd when I don't put my foot into it, to the point where often it will slightly skid the tires. Now that I'm a little older my car has become more of a cruiser, not as interested in racing it anymore.
 

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Just bought this 56. It ALWAYS shifts hard from 1-2. Chirps tires hard. Also shifts real hard from 1-2. All the other gears are fine. TV cable was replaced and set where it needs to be. Mechanic said it could have a corvette servo in it. All I know its really annoying chirp tires every time and can't be good for it.

So what do you think?

By the way, its great to be back on the forum!!
You should have someone else knowledgeable with your throttle valve settings take another look at it. A 1/4" over or under the correct setting will give you that hard shift. You can easily try adjusting the throttle adjusting fitting mounted on the cable. Loosen it and adjust it no more than a half inch up or down and see it makes a difference. When you find the correct setting, tighten the heck out if it to keep it from going back to it's problem location,
It worked for me.
Bob
 

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Can you by chance recommend a shift kit and a separator plate considering my circumstance? I called Summit and tried to explain it to them, but they said they only carry high performance shift kits. I'm good with high performance as long as the car shifts smoothly, currently shifts really hard from 1st to 2nd when I don't put my foot into it, to the point where often it will slightly skid the tires. Now that I'm a little older my car has become more of a cruiser, not as interested in racing it anymore.
I really like the Sonnax sure cure kits SC-4l60 & a experienced transmission man is your best bet (yes it is for 700r4 & 4L60) non electronic units these kits allow correction of some of the original issues inherent to these transmissions.The kits allow different options when installing for instance towing, performance,near stock just with mild shift improvements. One other thing if the trans shifts good in all other gears but the 1-2 shift don't try to adjust the TV cable to soften the shift you will end up frying the trans I seen several posts on here describing cable adjustments that are just plain incorrect. Go to the Sonnax web site they have some good information & videos. Plus a ton of other parts to make your 700R4 work better & live longer.
 

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I really like the Sonnax sure cure kits SC-4l60 & a experienced transmission man is your best bet (yes it is for 700r4 & 4L60) non electronic units these kits allow correction of some of the original issues inherent to these transmissions.The kits allow different options when installing for instance towing, performance,near stock just with mild shift improvements. One other thing if the trans shifts good in all other gears but the 1-2 shift don't try to adjust the TV cable to soften the shift you will end up frying the trans I seen several posts on here describing cable adjustments that are just plain incorrect. Go to the Sonnax web site they have some good information & videos. Plus a ton of other parts to make your 700R4 work better & live longer.
Thank you very much, I went with this option, ordered it online. Really appreciate the advice.
 

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Thank you very much, I went with this option, ordered it online. Really appreciate the advice.
Some of the items in this kit are designed to be installed when the trans is apart but many can be installed with the valve body & separator plate removed & the servo assembly on the side of the trans. You will probably need a new separator plate & need to identify the current servo. There is a servo that is used in 4L70e transmissions that is in between the stock V6-V8 servo & the corvette servo I've used it with good results nice firm positive shift but not harsh. Ideally you want the shift to be positive not harsh & progressively firm the more throttle applied.
 

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Some of the items in this kit are designed to be installed when the trans is apart but many can be installed with the valve body & separator plate removed & the servo assembly on the side of the trans. You will probably need a new separator plate & need to identify the current servo. There is a servo that is used in 4L70e transmissions that is in between the stock V6-V8 servo & the corvette servo I've used it with good results nice firm positive shift but not harsh. Ideally you want the shift to be positive not harsh & progressively firm the more throttle applied.
Yikes! I wouldn't wish rain on anyone's parade, but personally, I would give an experienced mechanic/transmission specialist another shot at adjusting the TV cable. I adjusted mine almost two years ago, went on a four hundred mile trip driving through Los Angeles traffic and been diving it ever since without a recurrence of the hard shift.
I have a 700R4 on another of my Trifives and the only problem I have with it is transmission fluid bubbling out on occasions but only when it's parked.
Bob
 

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To anyone interested take a moment & read The Real Art Carr's technical bulletin on adjustments of the TV cable + the correct geometry of the carb relating to the TV operation & what happens when the TV cable adjustment is tailored to try & correct a hard shift.Provided the carb geometry is correct it's pretty easy to adjust the TV. The problem occurs when the cable is lengthened to soften the shift in other words the body of the cable is pushed through the adjuster toward the carb attachment point while this may soften the shift it will also lower clutch apply pressure. I'm not a expert by any means but I have built transmissions since the early 70s you don't have to take my word but might want pay attention to someone like Art Carr. I glad you've had good luck many haven't
 

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To anyone interested take a moment & read The Real Art Carr's technical bulletin on adjustments of the TV cable + the correct geometry of the carb relating to the TV operation & what happens when the TV cable adjustment is tailored to try & correct a hard shift.Provided the carb geometry is correct it's pretty easy to adjust the TV. The problem occurs when the cable is lengthened to soften the shift in other words the body of the cable is pushed through the adjuster toward the carb attachment point while this may soften the shift it will also lower clutch apply pressure. I'm not a expert by any means but I have built transmissions since the early 70s you don't have to take my word but might want pay attention to someone like Art Carr. I glad you've had good luck many haven't
I agree,
I would get the bowtie overdrives tv made easy kit. it will help immensely with the tv system.
 

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My 56 700R4 has the Corvette spec build. If I don't give it more than 1/4 throttle it shifts smoothly, any more & it will chirp off 2nd gear. I have a choice of modes.
 
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