Gear whine/bearing noise

[rspinks]

I have a noise in the engine of my ’01 ETH that sounds like gear whine, or perhaps like a bearing/bushing that is in the process of going dry. It’s a medium pitch wooo-wooo-wooo sound at idle with a very distinct tone that I can hear from 40’ away with the engine idling. If you rev the engine off idle it sounds sort of like a roots type supercharger. I think I can just barely detect this tone on other ETH's, but it’s not nearly as noticeable as my truck and you certainly can’t hear it from 40’ off.



I got a mechanic’s stethoscope on the weekend and the noise seems to be coming from the top drivers side of the gear cover on the front of the engine. It can also be heard through the valve cover on the very front of the engine, but it seems to be originating from the gear cover. It’s not coming from the VP44.



Any thoughts on this? The truck seems to run fine, although I only got 176/520 on a Mustang dyno and get 14-17mpg unloaded. I only have 7000mi so I wasn’t too concerned about the power/mileage numbers. I don’t have the manual yet so I’m not sure what’s under the top right corner of the gear cover looking from the front of the engine.



Thanks,



Rich

 

[rubberneck]

DUDE, now that you mention it, i had the same exact noise when mine was new. I remember asking a buddy with the same truck if his did it, it didnt or at least he claimed it didnt. i just got used to it after a while, it really wasnt that bad. So i went out to listen to the truck to see if it was still there, and it aint. Maybe its just all the new gears in the gear covers needing to "run in" for a while. I wouldnt worry about it unless it gets worse, give it some time.

 

[rspinks]

Thanks Rubberneck, hopefully it is just the gears wearing in. Do you know what your mileage was when your noise stopped, or how many miles do you have now?

 

[rubberneck]

rspinks, i now have 22000 miles on the truck, and as stupid as it sounds, i actually had to go start the truck to see if the noise was still there, and it wasn't. I had asked a few people about it and everyone said to heck with it, drive it, and so I did. I just kind of tuned it out and forgot about it, not to mention, between the increased noise of the 4" exhaust and the B1 turbo, i just didnt pay attention to the gear whine anymore.

 

[rspinks]

I see from your sig that you have some serious bombing going on. Perhaps a straightpipe will help me by masking the noise for now, and an EZ will help to shorten the breakin period.

 

[rubberneck]

Originally posted by rspinks

I see from your sig that you have some serious bombing going on. Perhaps a straightpipe will help me by masking the noise for now, and an EZ will help to shorten the breakin period.

Now you're talking, bomb the heck out of it and drive it like you stole it. My truck has seen its share of smoke shows and sideways corners. Something sweet about powersliding a 7200 pound 20 foot long monster EZ will get you started, that was my first bomb at 90 miles on the odo, it just goes down hill from there

 

[rspinks]

I figured you would agree, most everyone on the TDR seems quite supportive of bombing. I'm still enjoying the power of the stock HO, having driven a 318 powered '94 3/4t for 5 years. The EZ may be added soon however, especially considering the Calgary Dyno Stampede is coming up and I'd like to get some numbers with and w/o the EZ.



I think I'll take it to the Stealer to get the noise on file, then to Cummins for an honest opinion on what's causing it. If there is no concerns then bombs away.



Thanks again Rubberneck.