I just found an old posting, actually from the predecessor to this site, about transmission shift adjustment. It was written by CDNSARGUY. He was good, I'd say on a par with anyone we have here. For unknown reasons he refused to move over to OB when this site was formed. I'll paste the entire post in here since it isn't too long.
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cdnsarguy
Member
Loc: Neepawa, Manitoba Canada
Re: Tranny Might be going out......... [Re:
pdxman]
#1400595 - 09/25/03 07:05 AM
I would ensure the manual shift cable is adjusted correctly and check engine for any vacuum leaks which could effect the VRV operation.
This info for later models if you have hard linkage not cable just loosen applicable bolts and adjust.
Automatic Transmission Shift Cable Adjustment
1 From inside the vehicle, place the select lever in drive. Hang a three pound weight on the selector lever ( six pack still full)
2 Raise vehicle on jack stands or hoist. (I'd block well and scramble under)
3 Remove shift cable from the transmission lever ball stud.
4 Pull down the lock tab on the shift cable body.
5 Position transmission lever in (D)drive position. This is three detents from the front-most lever position with the first position counting as one.
6 Connect the cable and end fitting to the transmission lever ball stud.
7 Push up on the lock tab to lock the cable in the correctly adjusted position.
8 Remove jack stands and lower vehicle from hoist. Remove three pound weight from column shift select lever.
9 After making adjustment, check for Park enguagment. Check the transmission control lever in all detent positions with the engine running to make sure correct detent/transmission actions. Readjust if necessary.
CAUTION:
Under no circumstances will it be permissible to adjust the cable in any position other than D for the C6.
Now all should be ok if it is in PARK and everything else works, remove blocks. (drink warm beer)
Notice:
These instructions are also applicable to the E40D, however the shift lever must be in OD (overdrive) for the E40D transmission.
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I hope this helps you.