Vibrating under hood

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Nov 17, 2019 | 03:36 PM

truckermark

Thread Starter

5th Wheeling

Joined: Mar 2017

Posts: 25

Likes: 1

Vibrating under hood

This is what vibrating. As you can see its got a nipple with no line on it. Its on the pass side

Hi. I have a e99 7.3l auto.
I have something vibrating under the hood anytime key is in on pisition. Its pretty loud. Not sure what this is. Any help is appreciated

Nov 17, 2019 | 03:40 PM

AllaboutMPG

Logistics Pro

Joined: Oct 2011

Posts: 3,953

Likes: 120

From: Mcdonough, GA

That's your vacuum pump. If it's running all the time you probably have a leak. Is yours 4wd and do your hubs still work?

Nov 17, 2019 | 04:00 PM

truckermark

Thread Starter

5th Wheeling

Joined: Mar 2017

Posts: 25

Likes: 1

Quote:

Originally Posted by AllaboutMPG

That's your vacuum pump. If it's running all the time you probably have a leak. Is yours 4wd and do your hubs still work?

Yes to 4wd. And i have manual leaver in cab and manual lockers. All work fine. Lockers are a luttle hard to turn though. What does this vaccum control?

Nov 17, 2019 | 09:09 PM

Brian Hanks

Fleet Mechanic

Joined: Apr 2019

Posts: 1,737

Likes: 661

From: South AR

If you have manual locking hubs then your vacuum lines that normally auto lock your hubs are disconnected. Make sure those lines are plugged. Mine had similar issues and previous owner had cut one side and left it hanging and on the other side was just missing. I didn’t know what was going on and one side was locked for several thousand miles before I figured out while on a lift spinning the tire to isolate a noise what was going on and switched to manual hubs and capped off lines. It caused the auto hub that was locked to wear out is the sound I was chasing at the time. You should have a nipple on your hub that you cap off and then the line runs into a bracket up near the wheel well. However yours may have been completely removed back at the pump.