Just got the trans installed this weekend and am noticing a sorta high pitch looping scraping sound. it's only when its locked and in OD. Everything shifts smooth and lockup goes in and out smooth and pulls super hard under acceleration. The sound goes away as soon as i let off the skinny pedal and seem louder when under a slight load. I have no carpet in the cab just bare metal floor so i can hear everything. With the windows cracked or the radio on i can not hear it its that quite.

in the video below i engage the lock up at second 24 and the noise starts then. Before that it was in OD but not locked.



sorry no exciting videos until i get this figured out

 

Looks like a nice ride in that truck, i think i'm getting motion sickness!

i couldn't hear anything but the motor. other than your paranoid noise, how do you like the new tranny?

any pictures of the install?

 

wow what a teaser video.

Your not paranoid, your making excuses to not take it out of valet and FLOOR IT.

HAHAHHAHAHA did anyone else notice theres no keys in the ignition.

I honestly don't hear anything Zach... All i hear is the engine and that goofy squeek monster that lives in your steering.

 

well here in PA we don't have the money to fix the roads right . they throw piles of cold asphalt in the craters in the road and let the traffic flatten it out.

Love it, there is no comparison to the 518 with a slipping converter.

 

There is a key in the ignition you just can't see it. it's hidden in there very deep (one of the previous owners dumb moves).

there really is a noise that is noticeable when Locked in OD. If you compare the first 5 or 6 seconds to the rest you can sorta hear it.

i also have to do some more adjustments on the T.V. cables to get full travel before i let it rip.

 

the ride is just as bad in my truck, i have to hold my coffee cup and use my hand to balance out the ride. if i put it in the cup holder its destined for the floor!

 

So what your saying is when you in OD with the converter unlocked you hear a noise, right?

Sounds to me, funny right, like your OD gears are a little noisey. Especially if it has straight cut gears. When your locked up and putting all that torque through there the noise really comes through.

 

when the converter is locked and in OD i hear it. As soon as i unlock it the converter or let off the skinny pedal it goes away. I don't hear it when locked in 3rd just OD locked.

 

Is it speed related? Does it change pitch as your speed goes up?

Might be nothing to worry about, probably normal considering all the torque your putting into there. Mine makes noises too, I don't worry about it anymore.

 

most noticeable around 55-60. The pitch does not change only the intensity when under a load. for say when i am locked around 55-60 and going up a slight incline it will become more noticeable. as soon as i pull it out of lockup it stops.

 

When I installed the 47RH in mine, I too heard a similar sound under similar conditions. It was more a 'gurgling' sound where yours in the video sounds like the straight-cut gears mentioned previously. Mine turned out to be the transmission dipstick tube touching/vibrating under load against the pinch weld on the firewall. My only guess why they would make the sound in lockup only is, well, the lockup converter itself, as it does really 'lock up' the input shaft, so the motor torques over just enough to rub, where in o/d only the converter still does slip, so the motor doesn't torque over as far? It makes contact there after the install due to the lockup converter bellhousing adaper is about 1 inch thicker, therefore relocating the dipstick tube back the same inch. I just carefully bent the tube down a bit(don't bend too much at once or it will kink/flatten out!! Trust me...) and then knocked the double-layered pinch weld back a bit for clearance. Voila! No more noise! :-) Hope yours is the same, good luck!