Patent Application
20120115673
1. Field of the Invention
The present invention relates generally to automatic transmissions, and more specifically to output shaft endplay adjustment method for GM automatic transmission 700r4/4l60e family.
2. Description of Related Art
Since GM first introduced the four speed automatic overdrive in the Corvette in 1982, the 700R4/4L60E family had many failures. It is understood that any reference hereinafter to the 4L60E/700R4 transmissions includes the 700R4/4L60E family from 1982 to present. The factory made improvements every year along with the aftermarket transmission improvement industry. But there are still a few problems remaining to be overcome. One of a few remaining failures is related to the excessive output shaft endplay occurred in GM 700r4/4l60e automatic transmission from 1982 to present.
The output shaft carries the drive train assembly this is called after assembly the “output shaft stack-up height”. The output drive train assembly wears quickly due to the output shaft placing thrust forces into the entire drive train all the way from rear thru to the front of the transmission. As the drive train wears the “drive train stack height” shortens from wear. As the stack height shortens the output shaft endplay increases.
If the output shaft endplay is excessive the shaft can contact the input shaft & restrict oil flow to the output shaft gear train causing failure. Excess endplay also causes ramming forces that can send damage thru out the transmission. On the 700r4 the excess endplay causes erratic shifting from the governor.
The factory has no published endplay adjustment for the output shaft endplay. During overhaul a method in needed to properly adjust output endplay. To make adjustments requires removing the entire output shaft gear train assembly to place a shim behind the ring gear. This existing repair procedure increases assembly time, making adjustments time consuming.
Even though the new factory transmission has the endplay preset between the rear planetary hub & the raised stop at the orifice. As the rear differential moves vertically over varying road surfaces the vertical motion changes to horizontal motion in the drive shaft. Thrust is transferred into the rear output shaft from the drive shaft. The thrust forces pass thru the [stack-up] gear train, then into the input drum, into the stator housing, into the front pump ending into the case. These causes wear throughout the transmission. On the output shaft this wear decreases the [stack-up] height; this in turn causes excess output shaft endplay.
There is no invention in the prior art that addresses these problems. Therefore, there exists a need to have an invention that provides a simple, easy, and time saving method/device to adjust the output shaft endplay for GM 700r4/4l60e family automatic transmission.
One object of the invention is to provide a simple, easy, and time saving method to adjust the output shaft endplay for GM 700r4/4l60e family automatic transmission.
A further object of the invention is to provide a method to adjust output shaft endplay without removing the entire output shaft gear train assembly.
Yet a further object of the invention is to provide a method which does not require disassembly of the stack-up, thus is time saving.
Yet a further object of the invention is to provide a method that can control thrust and prevent reoccurring endplay adjustments from wear.
One embodiment of adjusting the output shaft endplay without thrust control according to the present invention comprises placing special shims and a snap ring between the end of the rear planetary ring gear hub and the output shaft outer most oiling orifice which is the ring gear hub stop. This method does not require removing entire output shaft gear train assembly or disassembling the stack-up, and thus is more efficient than the existing repair method. This method can be used on all 700R4-4L60E-4L70-present. The shims & snap ring are placed on the output shaft between the output stop & the ring rear hub.
One embodiment of adjusting the output shaft endplay with thrust control according to the present invention comprises placing @Torrington bearing between the transmission case and the output shaft. The preferred method is using the @Torrington bearing for easy adjustment with no thrust loads placed inside the transmission. For the 700r 1982 thru 1993, the method requires a thrust plate, @Torrington bearing, split shaft collar. For the 1993 to present needs only @Torrington bearing, split collar, shims.
The more important features of the invention have thus been outlined in order that the more detailed description that follows may be better understood and in order that the present contribution to the art may better be appreciated. Additional features of the invention will be described hereinafter and will form the subject matter of the claims that follow.
Before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
The foregoing has outlined, rather broadly, the preferred feature of the present invention so that those skilled in the art may better understand the detailed description of the invention that follows. Additional features of the invention will be described hereinafter that form the subject of the claims of the invention. Those skilled in the art should appreciate that they can readily use the disclosed conception and specific embodiment as a basis for designing or modifying other structures for carrying out the same purposes of the present invention and that such other structures do not depart from the spirit and scope of the invention in its broadest form.
Other aspects, features, and advantages of the present invention will become more fully apparent from the following detailed description, the appended claim, and the accompanying drawings in which similar elements are given similar reference numerals.
The following detailed description is of the best currently contemplated modes of carrying out exemplary embodiments of the invention. The description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention, since the scope of the invention is best defined by the appended claims.
Referring to
Partial of the transmission before and after assembling using the first embodiment is illustrated in
The preferred method to adjust endplay is to use a @ Torrington thrust bearing between the transmission case and output shaft. This will prevent reoccurring endplay adjustments from wear.
The embodiment comprises: installing output shaft components with output shaft, installing thrust plate into rear of case, then installing on the output shaft the @Torrington bearing with feeler gage 0.010 to 0.020 thousands between bearing and thrust plate; pushing Torrington bearing and feeler gage into case tightly with one hand and pulling output shaft outward; installing split collar; removing feeler gage; installing spacer plate between case and tail housing; sealing with rtv sealer; and checking endplay.
Referring to
Partial of the transmission after assembled by the second and/or third embodiment is illustrated in
To make the invention manufacture steel washers to go over the output shaft to be placed against the output shaft ring gear thrust stop.
While there have been shown and described and pointed out the fundamental novel features of the invention as applied to the preferred embodiments, it will be understood that the foregoing is considered as illustrative only of the principles of the invention and not intended to be exhaustive or to limit the invention to the precise forms disclosed. Obvious modifications or variations are possible in light of the above teachings. The embodiments discussed were chosen and described to provide the best illustration of the principles of the invention and its practical application to enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are entitled.
This patent application claims the benefit of U.S. Provisional Application No. 61/409,231 filed on Nov. 2, 2010 the disclosure of which is incorporated herein by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 61409231 | Nov 2010 | US |
