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Just finished this mod after staring at the package for 6 months. I had a slip from 1-2 and a fairly strong jolt going into 2nd unless I feathered the throttle back. This mod fixed everything. Should have done this 6 months ago.

The only problem I had was re-installing the cover clip. I though I was compressing the cover all the way and for the life of me I couldn't get the clip in. Took a deep breath and a fresh look at the pics on this and other sites and realized I was not compressing the cover all the way...just had to be brave. Clip went right in. Highly recommended.
 

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So what's the fix when your snap ring didn't seat properly and you drive it and now the servo is jammed?? How do I fix this. I can't get it to budge at all


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Nice write up!
 

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This is Brian from Oregon Performance Transmission. Just wanted to say thank you for the mention(s) here. We really appreciate the support for our business.

Not long ago we put together a short blog post about the corvette servo. It's featured on our commercial website, http://oregonperformancetransmission.com, under the blog tab; or you can click on the link below and it should take you right to it.
http://blog.oregonperformancetransmission.com/?p=390

If you have any questions or if we can help out with anything, please do not hesitate to contact us at [email protected].

Thanks again.
 

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Yes, the amount of reoccuring threads inquiring about the additon of a corvette servo has lead me to creating a master thread here. I believe there have been 6 threads regarding this just in the last few weeks.

In this thread I am going to attempt to answer more of the questions related to the servo swap instead of writing another how-to on it as both KevinDepot and FatKidKustomz have already completed two thorough install how-to's. Okay, here we go.


First of all, the addition of a Corvette servo can be done to all 700-R4/4L60e transmissions. 1982 introduced the 700-R4 trans to the world. The trans remained the same until 1993, although in 93 it was renamed the 4L60. In 1994, GM rear-wheel drive vehicles got the new electronic controlled 4L60-e. The 4L60e has remained in the 1/2 ton series truck until present time. If you have a 4speed auto in your 1500 series, 94 and newer, then it is a 4L60-e, so YES, the vette servo WILL work in it. That's all 700-R4's 82+Present and 4L60-e's 94-Present (2008).

The servo is located inside of the servo housing that is located on the passenger side of the transmission. The servo swap can be performed with the transmission in the truck and also without dropping the transmission pan. Depending on the exhaust setup, you may have to disassemble the servo assembly in the housing. See the How-To write-ups for more info.

The purpose of the vette servo mod is to allow the transmission to shift more quickly and efficiently from first to second gear. From the factory, the truck 4L60e's have a smaller servo. The servo is used to apply the 2-4 band in the transmission. Upgrading to the vette servo gives the trans more "holding" power and thus yields a quicker/firmer shift. Adding a vette servo has also seemed to cause some folks 1-2 slipping to cease. Below is a photo of the stock truck servo (left) and vette servo (right).
View attachment 272524

The easiest place to get a servo is from Oregon Performance Transmission off of ebay. I belive they're $17.95 shipped. Their username on ebay is oregonperformancetransmission. You can also try searching using phrases such as "CORVETTE SERVO, 700R4 4L60, 4L60-E." Often, you will see the servos being sold with a longer pin. You do NOT need the pin. I've read where it only offers 1/32" of end play for the cover so it makes no difference at all. Below are the links to the how-to's.

The biggest difficulty that you may run into while installing the servo is getting the servo cover back on with the snap ring seated properly. Take your time, it will go on. If you do not get it seated properly, you will cause the servo assembly to jam inside the housing and worst case, you will ruin the housing. Below are the how to articles that provide more in depth installation instructions.


HOW-TO:
Vette servo install

Corvette Shift Servo Install w/ pics



I'm sure I've missed something. Everyone feel free to add/correct anything that I have may missed. Maybe we can put an end to these threads...

Edit: Thanks to Eric for this:shake:
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I have disassembled and 85 Corvette transmission to go back in my 91 Silverado. When I removed the Corvette servo I found a broke spring and the apply rod is in pieces. Can you tell me what caused this. I don't want to rebuild it and the same thing happen again. Thanks for any help.
 
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