Tranny noise, help diagnosing please? Video link inside

[22lbChevelle]

Hello,

Background: Tranny was rebuilt by the go to guy in the seattle area back in 2006. Since finishing the megasquirt project in August I havent gone WOT because I dont have the alky installed and the tune isnt perfect for high boost. I'd say no more than 75% throttle and 10psi.

I was driving to my grandpa's after work and pulled over to test the launch control feature, I was building roughly 5psi on the spark cut and letting off, not actually launching the car. I did this for about minutes then I drove on down the road. Got about a mile out and the tranny started making a buzzing noise so I drove it home.

SO, here are the symptoms:

I can start the engine, warm it up, and there will be no noise.

The second I put it in gear I get a buzzing sound that is coming from the front of the tranny. Here is a link to a video I took this morning:

transmission fail - YouTube

If I put the tranny in neutral it will stop making noise. If I throw it in reverse the noise comes back right away, and it takes about a full second to get into gear.. If I put it into drive again, the noise changes pitch a little bit and it takes a second to get into gear.

On my drive home after the noise initially started, it didnt seem to make the noise or have any problems on the highway but once I slowed and got into the lower gears it came back.

Also, it may help to know that the converter lockup quit working 2 days before this happened.


So do any tranny gurus know what this might be? From my research it sounds like the pressure reg? Any chance it is the torque converter? Will I harm the engine if I drive it roughly 20 miles to my new apartment with a garage where I can pull the tranny out?

Thanks and let me know what more info I can provide!

 

[22lbChevelle]

Anyone able to watch the video and get an idea of what the problem might be?

I want to make sure that the converter isnt gunna balloon and ruin my engine's thrust bearing.

 

[SSedan64]

Sounds like a bad Bearing or Roller Clutch, possibly OD roller clutch.
Chart may help diagnose >> Transmission Shifting

 

[22lbChevelle]

Thanks SSedan64.

Is this something that I should not try driving on? I am moving and would like to make one last drive to the new place where I am gunna upgrade to a 4l80e this winter.

I pulled the pan last night and there are no parts laying in it, only the usual dust layer some tiny chunks. The I would describe the chunks as heavier than normal clutch wear, they didnt seem magnetic when I picked some up on my finger and place my finger on a magnet.

 

[SSedan64]

I can't say for sure if it would cause any more damage, if you do choose to drive it be very gentle.
Maybe one of the Trans Gurus will give a listen & more Info.
How far do you have to drive?

 

[22lbChevelle]

I have to go about 15 miles. I am optomistic about it because on the way home after hearing the noise it was mostly highway miles and I didnt hear the noise until I got below about 25 MPH. The cruise to the new garage is just about all highway driving.

 

[22lbChevelle]

For the sake of not leaving this thread without an end, I made the 20 minute drive to the new place. No problems what so ever. It only seems to be making a grinding noise when putting it into reverse.

Now on to the 4l80e build!