For a while now I've heard a vibration or rumble in the engine bay. Engine runs smooth. Only leak I have is the front cover and its not much of a leak. Thought maybe the turbo, but took off the tubes, and reached in and found no side to side play.... and from what I read turbo squeal, not vibrate. I was even ready to buy a new turbo, but then I thought I better find out what this noise is first. Would hate to find out my crank was going or something serious after spending money on a turbo.

Noise comes & goes... not a continuous noise. Thinking maybe power steering pump, but no play or leaks... although I reached thru wheel well, and thought the hose was vibrating more than it should, just sitting there idling.

Thought about torque converter, but it was replaced like 40k ago. But noise still sounds up in engine bay to me.

I'll try to get a video of sound tomorrow

Any thoughts ?

 

Vacuum pump


Remove your drive belt and spin all the accessories idler pulleys, they seem to be the most common noise generators

Jack up the front axle and check your front tires for out of round from ply separation

 

Remove belt and spin all pulleys.
start it up and see if bottom pulley runs true. If it wiggles at all then balancer is shot. Get a melling oil pump while in there if not done. Just four more bolts. Check water pump shaft and fan clutch for any play.

​​​​​​Check flex plate on trans and TC bolts.

 

Flex plate sounds pretty plausible to me. They are known bust between the mounting holes.

 

Or a weak belt tensioner.

 

Has a new belt tensioner, I replaced that when I replaced most of the a/c units.
Took off the belt yesterday, and vibration was still there.
Took cover off flex plate housing, and couldn't see anything that looked cracked, etc. But it seemed to me, that was where vibration was coming from.
So I took it to A1 Transmission in Royston,GA to let them see what they could find. He was a bit perplexed with the vibration too. Maybe torque converter, but we'll just have to see. They replaced my tranny about 50,000 miles ago. Was a 90+ mile drive, all the while wondering will it blow up before I get there in this crazy Atlanta traffic Another 10 miles I'd have been at Sous's house... Will just have to wait and see.
Oh... took it to local diesel shop Tuesday. Asked about costs for front cover seal or whatever is leaking in front of engine. And the vibration issue. Two weeks for an appointment.... maybe 3 weeks for repairs after that. Geezzz
But then he lost my business when he said they've have to pull engine to replace the front seal, etc.... uh... I don't think that is necessary.

 

The ‘front seal’ is the LPOP and harmonic balancer.

But, to reseal the front cover requires oil pan to come off and that does mean engine R&R.

Cracked flex plate can make HELLACIOUS noise. It can be a low grumble that resembles loose main bearings or a high pitched growl/roar that is nearly deafening. You can’t see this problem until removing TC (transmission). Can’t really say I’ve observed one causing a vibration though...

Is there rubber poking out of harmonic balancer? Does it look round/true when it spins?

 

You were very close to us and we likely passed you going the other way to meet John in Okieland in Commerce.

We used to go to Royston for Chinese takeout before Hartwell was lucky enough to have a place open up. Drive safe Bill, people are crazy on the roads and more so during the holidays.

 

The ‘front seal’ is the LPOP and harmonic balancer. But, to reseal the front cover requires oil pan to come off and that does mean engine R&R. ugh....

Cracked flex plate can make HELLACIOUS noise. It can be a low grumble that resembles loose main bearings or a high pitched growl/roar that is nearly deafening. More or less what I meant... lets not talk main bearings.... geezzz

Is there rubber poking out of harmonic balancer? Does it look round/true when it spins? It looked fine to me

Guess I'll know more when they pull tranny

 

Got my truck back from A1 Transmission. Bad Flex Plate and replaced Torque Converter. Vibration is gone.... everything seems to shift smoother, firmer... maybe this has been a slow long time problem that finally got bad enough to know something was wrong.

On to the next project...

 

Enjoy the truck!

 

Glad to hear that’s ‘all it was’. Not a ‘cheap’ fix, but easily diagnosed and a solid repair. I hope they didn’t treat you too bad!!

 

Well.... I'm hoping the old Gal will last another 200,000 miles or 10 + years. By then I'll be approaching 85, and the kids will probably be trying to take my keys away !

 

I have heard that a taser, or pepper spray works wonders...remember the best defense is a good offense. I like Offence

cheers