Addition Kit Information:
In the 4L60E/65E/70E-700R4 type transmission the 3-4 clutch is contained in the input drum. The clutch is applied when hydraulic fluid moves the 3-4 piston causing
the 3-4 apply ring to engage the clutch. Over the years all these parts have been updated by General Motors. In an automatic transmission it has been proven if
you increase the number of frictions in a clutch set up you can increase the torque handling capability of that particular clutch. One issue with this theory,
to increase the number of frictions the steels must be thinner to get proper clearance. The 3-4 clutch in this transmission does not work well with thin steels
because it is a shifting clutch and the thin steels have an inability to dissipate heat causing the steels to warp, especially in high performance applications.
General Motors went from a five friction setup in 1982 to a seven friction set up with six .097" thick steels in the later model 4L65/70E heavy duty transmissions.
However, in the standard 4L60E transmission up to 2010 model year GM used a six friction setup. This Trutech Performance Module contains the Raybestos
Stage One seven friction, six .097" thick steel clutch components. To install this clutch correctly we have included all the additional factory parts necessary
to achieve proper clutch clearance. All OEM parts included in our Overhaul Module are high quality and meet or exceed factory specification.
At Trutech Performance Transmission we have found the Raybestos Stage One frictions to be an excellent high performance friction. When using a high
performance low slip friction it is necessary to calibrate the shift times to engage the shifting clutches quickly. Because this is necessary we highly
recommend one of our shift modules.
To ensure hydraulic intregrity our Overhaul Module contains the updated steel molded 3-4 pistons. There is one check valve that are very important to 3-4
clutch life. This check valve is the 3rd accumulator check valve. This valve has a direct effect on 3-4 clutch operation. We include this check valve
in all our kits, we consider this low cost insurance.
In this General Motors transmission bushings play a large part in hydraulic intregrity. In a lot of rebuilds, the bushings are not replaced if they "look" good.
Our recommendation is replace all bushings in your overhaul.
In the 4L60E/65E/70E type transmission the band is applied to move the vehicle forward in the 2nd and 4th gear range. In our High Performance Build Modules we use
the Alto extra wide carbon band with heavy duty anchors. When using this extra wide band we strongly recommend replacing the reverse input drum to give the
band a new wear surface. However, the drum can be reused if it has no signs of wear. Replacing the drum is always a good idea but not always necessary
when using the stock width band. Do not reuse the drum if it is discolored from heat or is warped in the band apply area.