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Old 07-25-2012, 12:13 AM   #1
74baggedbug
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Clatter/rattle

What could be causing my motor to clatter/rattle when it goes into 4th gear.. I've pulled the valve covers and nothing loose. It's when I'm driving normal and go into 4th but if I'm getting on it it won't rattle at all.. Some1 told me its due to the rpms dropping to low but I'm lost. thanks for any advice/tips
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Old 07-25-2012, 01:33 AM   #2
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Re: Clatter/rattle

ttt
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Old 07-25-2012, 05:48 AM   #3
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Re: Clatter/rattle

most likely low rpm is the cause.... what rear gear do you have?
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Old 07-25-2012, 09:39 AM   #4
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Re: Clatter/rattle

Detonation! What's your timing set at?
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Old 07-25-2012, 11:24 AM   #5
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Re: Clatter/rattle

i would also say your letting your r.p.m.'s get to low, and your timing may be a little to advanced....try to shift so when you go into forth your rpm is still above 1000 rpm....
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Old 07-26-2012, 02:54 AM   #6
74baggedbug
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Re: Clatter/rattle

Don't know what size gear the truck has it was that way when I bought it.. I'll double check the timing .. Can't keep the rpm's up its a automatic ... Thanks for the tips
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Old 07-26-2012, 03:42 AM   #7
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Re: Clatter/rattle

Loose torque converter bolts,,, when your accelerating or decelerating the bolts are anchored to the flex plate,,, when your cruising the bolts are banging back and forth in the flex plate holes.
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Old 07-28-2012, 02:24 AM   #8
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Re: Clatter/rattle

So,,,,have you figured it out yet???
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Old 07-28-2012, 05:47 PM   #9
74baggedbug
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Re: Clatter/rattle

No I've been stuck out here at work working a lot of OT but now I have a bad missing/idle problem so 1st I gotta figure that out and go from there... I'm pretty sure the idle is related to carb/fuel ... I'll tear into it maybe tomorrow night or monday thanks
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Old 07-28-2012, 11:35 PM   #10
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Re: Clatter/rattle

Bad missing idle could also be too much timing. An easy check is to remove and plug the vacuum hose to your distributor.
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Old 08-04-2012, 07:41 AM   #11
74baggedbug
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Re: Clatter/rattle

Update: had the carb rebuilt and timing checked/set, so she's puring like a kitten now.. Also rewired the alt to charge properly.. Double checked the torque converter bolts as they were tight... Ran it by buddy's shop and we took it for a spin and he said the same things a few of y'all said and it's the RPM's are dropping to low when it goes into OD... Time for some 3.73 or some 4.10's thanks for all the help
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