1999 GMC Sierra Hard shifting

1999 GMC SIERRA
153,000 MILES • 6 CYL • 4WD • AUTOMATIC
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SEMPERFISH76
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The tachometer in my truck quit working a while back, and ever since the truck seems to shift hard from park to drive or reverse, as well as occasionally jerking at cruising speed. I had a buddy check the codes showing up, indicated a bad camshaft position sensor. I replaced it and it seemed to relieve some of the jerking at higher speeds, although not completely. Also, the tachometer is still inoperable & truck still shifts hard from park to drive & reverse. Any ideas? The transmission seems to be ok fluid wise & all, no leaks. I'm thinking there has to be some kind of sensor from the transmission or motor to the tach or vice versa. Any help would be appreciated!
Aug 17, 2008 at 12:39 PM
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MASTERTECHTIM
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i know the tachometer ignition feed is from the transmission fuse. make sure the transmission fuse, i think its fuse 20, is getting power when key is in run position. also you need to check for transmission codes, usually they will not turn on the check engine light but will be in history, get back to me with the codes if you can.
Aug 19, 2008 at 7:28 PM