New USA made Corvette servo piston kit with a longer Servo Pin for the GM 700R4, 4L60, 4L60E, 4L65E, 4L70E, 4L75E THM700-R4 MD8
This package includes a longer than stock servo pin to get your band adjusted to the right clearance. It's almost more important to get the right clearance as it is to change to the Corvette servo. If you push in on your servo cover, you'll notice that it moves in around 1/8"-1/4". This is way too much travel, it should be closer to 1/16".
This servo is a must for any performance, towing, RV, or off-road transmission, but would be a nice upgrade for any 700-R4 or 4L60E.
Right away you'll notice faster and firmer 1-2 shifts and even slightly better 2-3. Also, since the servo isn't traveling as far before it applies the band, the 1-2 and even the 3-4 shift will be much quicker.
This servo will give your transmission 50% more apply pressure, just what you need to keep from burning your transmission up under heavy load situations.
This servo is easy to install and can be done with the transmission in the vehicle.
The kit comes with all of the necessary seals for installation including the outer cover o-ring.
This servo works in all makes of this transmission. GM, Cadillac, Chevrolet, GMC, Pontiac, Oldsmobile, Hummer, Isuzu, Saab, including:
- Astro Van 1985-2005
- Avalanche 2002-2008
- Blazer 1982-2005
- Bravada 1991-2004
- Brougham 1994-1997
- Camaro 1982-2002
- Canyon 2004-2012
- Caprice 1982-1996 (With optional 700R4)
- Colorado 1994-2012
- Corvette 1982-2005
- Custom Cruiser Wagon 1991-1992 (With optional 700R4)
- Envoy - XUV - Denali 2001-2010
- Firebird and Trans Am 1983-2002
- Fleetwood 1994-1997
- GTO 2004-2006
- Hummer H2 2003-2007
- Hummer H3 2006-2011
- Impala SS 1994-1996
- Isuzu Ascender 2003-2009
- Isuzu Hombre 1996-2000
- Isuzu Pickup, I280, I350, I290, I370 2006-2009
- Rainier 2004-2007
- Roadmaster 1992-1996
- SAAB 9-7 2005-2009
- Safari Van 1985-2005
- Sierra Pickup 1982-2013
- Silverado Pickup 1982-2013
- SSR 2003-2007
- Suburban 1982-2013
- Syclone 1991-1993
- Tahoe 1993-2013
- Trailblazer 2001-2009
- Typhoon 1991-1993
- GMC and Chevy Van 1983-2013
- Yukon 1993-2013
Industry Part Number: K77895
OEM Exchange # 8642079, 8673039, 8647351
These transmissions are part of the Turbo-Hydramatic series and are also known as: 700R4, 4L60, 700-R4, TH700-R4, MD8, THM700R4, THM700-R4, 4L60E, 4L60-E, 4L65E, 4L65-E, 4L70E, 4L70-E, 4L75E, 4L75-E, M30, M32, M70
Frequently Asked Questions
1. Why buy the servo with the longer pin?
After a short amount of time, by 30k miles or so, the band has been broken in and the servo travel has increased a lot. Too much servo travel can cause a delay in shifting, a longer 1-2 and 3-4 shift. It can be a slide-and-bump into gear. By 100k or more miles, the band is wearing out and then you are at the point where the servo almost can't travel far enough, and once it is beyond the travel of the servo, it will burn up the transmission.
You can test your current travel now. Just get under it and with a pry bar, push in on the cover of your servo. If it goes in more than 1/8", you definitely want the longer pin. The optimum range is closer to down around 1/16"+ or so (.070 – .090).