Corvette Servo Questions

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Justinj360

Justinj360

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So I just found out that you should change the pin as well to the longest pin to reduce play. Has anyone done that? I bought what was suppose to be the longest pin from ACDelco but when I pulled mine out they were exactly the same length. Mine had 2 grooves on the tip and the new one has no grooves. I read that no grooves is the longest. I'm confused by this.

I bought this one:
https://www.amazon.com/gp/r.html?C=...71LFCVWSA36IAA&ref_=pe_623860_70668520_dpLink
 

Goodinblack

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I think the main thing is to seat the snap bring back in all the way into the groove. Clean the groove out before putting the snap ring back in as well.

I read stuff about people not seating it in right and the case blows and cracks

Sent from my SM-N910V using Tapatalk
 
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Justinj360

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I think the main thing is to seat the snap bring back in all the way into the groove. Clean the groove out before putting the snap ring back in as well.

I read stuff about people not seating it in right and the case blows and cracks

Sent from my SM-N910V using Tapatalk

Maybe I wasn't clear about which grooves I was talking about. I meant the grooves on the end of the pins (which the one from Amazon doesn't have any).
 
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Justinj360

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I made a mistake, the pin with no grooves is in fact a little bit longer. I didn't compare them closely enough. The long one is about 3/32" longer than the pin with two grooves. I thought it would be more noticeable than that.
 

Chubbs

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I called around when I was in the market for an upgraded servo and let an old transmission tech talk me out of it. I wanted to swap bc @Justinj360 the shift points are really weak & relaxed like you had said about the truck you are/were driving. The 3-4 shift on light throttle really stretches like you aren't supposed to notice that it's happening.

I'm here to request your experienced input and see if you still are of the same position. I assume you would have commented had any failure occurred since the replacement. Is there any evidence of negative, unforeseen consequences with the bigger servo and corresponding pressure on the band? I have read of band failures which helped me reconfirm my decision but I have yet to see any testimonial of failure that was or possibly could have been directly attributable of the corvette size servo.

I would use the full kit with the pin if I were to join the bandwagon. The majority of folks do not use the longer pin so that also gives me pause: would the longer pin introduce a distinct variable in regard to the band, and so forth..

I think there are 3 dif sized OEM pins and if all trans are built to the same specs on the same production line, there will not be a noticeable difference in pin length. You are supposed to be able to file that pin down to your application and required specs; I guess it is designed to account for wear within the unit. I watched a YouTube video and the tech used a couple of specialty Kent-Moore tools for gauging that pin length requirement on a trans rebuild. It is my opinion that getting involved with the pins could 'make it or break it' so I would have to know exactly what I'm doing if I take that additional step.
 
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HiHoeSilver

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I called around when I was in the market for an upgraded servo and let an old transmission tech talk me out of it. I wanted to swap bc @Justinj360 the shift points are really weak & relaxed like you had said about the truck you are/were driving. The 3-4 shift on light throttle really stretches like you aren't supposed to notice that it's happening.

I'm here to request your experienced input and see if you still are of the same position. I assume you would have commented had any failure occurred since the replacement. Is there any evidence of negative, unforeseen consequences with the bigger servo and corresponding pressure on the band? I have read of band failures which helped me reconfirm my decision but I have yet to see any testimonial of failure that was or possibly could have been directly attributable of the corvette size servo.

I would use the full kit with the pin if I were to join the bandwagon. The majority of folks do not use the longer pin so that also gives me pause: would the longer pin introduce a distinct variable in regard to the band, and so forth..

I think there are 3 dif sized OEM pins and if all trans are built to the same specs on the same production line, there will not be a noticeable difference in pin length. You are supposed to be able to file that pin down to your application and required specs; I guess it is designed to account for wear within the unit. I watched a YouTube video and the tech used a couple of specialty Kent-Moore tools for gauging that pin length requirement on a trans rebuild. It is my opinion that getting involved with the pins could 'make it or break it' so I would have to know exactly what I'm doing if I take that additional step.

You read this ever?

https://www.performancetrucks.net/f...22/corvette-servo-install-w-alot-pics-476223/

I got one with out the pin. Yet to install.
 

cmc76

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I did a writeup when I did mine last year. I did the full swap with pin.
You don't have to drain the pan. But will lose some fluid. It is messy.
Work clean. Work slow .And I used a piece of oak. 1"×2" about 18" long. Used for leverage to push the cover in while . Seating the retaining clip.
I found using the board off the frame rail. Held in my armpit way easier than 2 sets of hands under there slipping in trans fluid.
 
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Justinj360

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I called around when I was in the market for an upgraded servo and let an old transmission tech talk me out of it. I wanted to swap bc @Justinj360 the shift points are really weak & relaxed like you had said about the truck you are/were driving. The 3-4 shift on light throttle really stretches like you aren't supposed to notice that it's happening.

I'm here to request your experienced input and see if you still are of the same position. I assume you would have commented had any failure occurred since the replacement. Is there any evidence of negative, unforeseen consequences with the bigger servo and corresponding pressure on the band? I have read of band failures which helped me reconfirm my decision but I have yet to see any testimonial of failure that was or possibly could have been directly attributable of the corvette size servo.

I would use the full kit with the pin if I were to join the bandwagon. The majority of folks do not use the longer pin so that also gives me pause: would the longer pin introduce a distinct variable in regard to the band, and so forth..

I think there are 3 dif sized OEM pins and if all trans are built to the same specs on the same production line, there will not be a noticeable difference in pin length. You are supposed to be able to file that pin down to your application and required specs; I guess it is designed to account for wear within the unit. I watched a YouTube video and the tech used a couple of specialty Kent-Moore tools for gauging that pin length requirement on a trans rebuild. It is my opinion that getting involved with the pins could 'make it or break it' so I would have to know exactly what I'm doing if I take that additional step.

Now I am by no means a transmission expert.
But I do know that installing that corvette servo was one of the best, cheapest, and easiest upgrades I've done to my truck. It was one of the first things I installed in it. I bought my truck over 4 years ago with 130k miles, one owner, bone stock. It now has 203k miles without a single transmission problem. I've changed the transmission fluid and filter once (Doing it again soon) and I don't baby the transmission. I romp on it when I feel like it (which is often), I tow a good sized trailer with it pretty regularly, and I down shift at highway speeds when descending hills.
I installed the longer stock pin recently because I just found out about it. I didn't really notice anything at all although I have yet to tow with that in. If that pin was swapped without my knowledge I would have no idea that anything was changed. I definitely noticed a lot more changes with the different servo.

Bottom line is there is absolutely nothing to lose with this upgrade, when installed correctly, and everything to gain. I would at least try it for a while and if you don't like it, take it out. But I don't see any reason why you wouldn't love it.
 

Chubbs

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Fantastic. Appreciate your testimonial, bub. Very solid info

I'm also encouraged by your going back & swapping in the relevant pin so that's an added bonus from which I have drawn my conclusions.

And all the major systems on your rig are the originals?
 

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