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Old 12-29-2015, 10:08 PM   #1
Super_Dave
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Wiper question...

My Forrest Gump question to end the year with...

I have noticed that my wipers really slow down when I am idling and work great once I get the rpm's up. So, not being that well versed in the overall wiper system, it seems it runs, to some extent, on a vacuum of some sort, rather than 100% electrical.

If my assumption is correct, can the wipers be made to work only on electrical and eliminate the vacuum?

Forrest Gump
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Old 12-29-2015, 10:25 PM   #2
ray_mcavoy
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Re: Wiper question...

The wipers in these trucks are 100% electric.

What you are experiencing is most likely a voltage drop due to the alternator not producing as much power at lower engine speeds. You can confirm this by hooking up a voltmeter if your truck doesn't have one already. If that's the case you'll want to give the charging system a thorough check and repair or upgrade as necessary.
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Old 12-29-2015, 10:33 PM   #3
4 Wheelin Fudpucker
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Re: Wiper question...

Last vacuum wipers were in 72.
I also ran another ground wire to the wiper motor
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Old 12-30-2015, 09:09 AM   #4
gmachinz
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Re: Wiper question...

I've had good experiences running the main motor power through a relay and powering the relay off the main firewall junction along with a better case grounding wire too.
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Old 12-30-2015, 05:12 PM   #5
Super_Dave
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Re: Wiper question...

Thanks guys.

My mama always said working on these trucks is like a box of chocolates... you never know what you're gonna to get.

Forrest
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Old 12-30-2015, 10:03 PM   #6
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Re: Wiper question...

If you go out and open the box (hood), and look at the chocolates (wiper motor), then extrapolate next time, we can call you Dave in the future...
We're all Forrest over and over. I find that when I'm sure that something isn't the problem, and don't need to look at that bit it's the time to look at that again on the next pass. Or, when the problem isn't solved, its probably the part you're sure isn't the problem.

Last edited by franken; 12-30-2015 at 10:11 PM.
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