Help with a "knock"
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Joined: Aug 2011
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From: tulsa, Ok
Help with a "knock"
Okay so i picked up a 85 302 FI for 600$ and have been going though the process of fixing things here and there. But I can't seem to figure out what might be causing well, a "knock" or jerk when going between 35-45. Like for instance if i set cruse at 45 once it gets up to speed and lets off it kinda like grabs once it picks back up again. transmission shifts great and its not down shifting or anything. So in short let off the accelerator then jump back on it again there is a notable grab and knock going on..
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From: Virginia
Block the wheels so it won't roll. Turn the keyswitch a little bit so you can put the auto tranny in neutral. Get under the truck and grab the driveshaft and try to turn it. If there is a lot of slop in it, then figure out where it's coming from.
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Joined: Jun 2009
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From: Wagener, SC
Okay so i picked up a 85 302 FI for 600$ and have been going though the process of fixing things here and there. But I can't seem to figure out what might be causing well, a "knock" or jerk when going between 35-45. Like for instance if i set cruse at 45 once it gets up to speed and lets off it kinda like grabs once it picks back up again. transmission shifts great and its not down shifting or anything. So in short let off the accelerator then jump back on it again there is a notable grab and knock going on..
Could be a few things. Bad u-joints, rear end gone sloppy, loose or broken engine and/or transmission mounts.
Does the truck "klunk" when you shift from park to drive, or from park to reverse?
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Joined: Aug 2011
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From: tulsa, Ok
The gears engage fine nothing odd there. Put it in neutral and I can feel some play in the drive shaft. Though this being my first rwd car I am unsure on what is considered normal.
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