zildjian4life218

Any ideas where to start looking? Sounds like it's coming from the trans. It's a 2004 4l80e, hd2 with a 3600 stall yank converter. It started after I topped off the fluid. I noticed the converter stopped locking up and checked the fluid and it was just below the low side of the hash marks. Put a couple quarts in and the fluid line is just above the hash mark on the stick and converter locks up great again. Next morning started making this noise. Seems to only happen when cold. Still shifts great. Maybe this weekend if I have time I'll drop the pan and inspect the fluid and also measure the pan rail to the dip stick.
https://youtu.be/LKADfcldMZ4
https://youtu.be/perohFSAT6k

Jake's Performance

iTrader: (2)

Fluid level is critical. You may have cooked the clutch in the converter and it's metal on metal making the noise.

zildjian4life218

I dropped the pan and there is no signs of metal chunks. Just clutch material. This fluid has maybe 1000-1500 miles on it.

Jays_SSZ28

iTrader: (2)

Break the filter open, theres usually more in there than the pan.

madmann26

Mine has whined in 1st since it was rebuilt in Feb.

Some say it's the straight cut gears. It's never given me an issue so I just drive it. It IS annoying sometimes but meh.....whatever.

zildjian4life218

Mine does it in 1st, 2nd and sometimes 3rd. Usually very briefly though. I thought the straight cut gears were only found in very heavy duty applications? My trans came out of a 1ton express van. Wouldn't think that it would have them.

Jays_SSZ28

iTrader: (2)

The 1997 4L80E in my 1992 454 dually came out of a 3500HD tow truck and had a brake on the tail housing. It doesn't have straight cut gears and it whines in 1st to 2nd. Not like the video though.
I think you caught a worn clutch just in time to rebuild it before metal gets all in everything.

zildjian4life218

Also I went through the datalog last night and noticed the temps hit 215 at one point....

zildjian4life218

So I measured the dipstick. The top hole on the dipstick for the full mark is about 3/8" below the rail. So I definitely had the fluid too low. Using the 1/4" above the rail recommendations I should be filling it to 5/8" above the full mark...... Oops

zildjian4life218

So yesterday I sat down and decided to change out the filter and flush out the fluid and see if that fixed it. If it didn't I was at the point of pulling the vehicle off the road for the year.

So after 2.5 gallons of fluid and a fresh filter it no longer makes any noises.... I let it idle and get up to temp in my driveway, ran it through the gears and filled the fluid,took it for an easy cruise around the block and topped off the fluid again. Did a couple spirited pulls and no noises. Took it out first thing this morning when it was cold, no noises. Not sure what was going on but I'm hoping it's fixed. At least for the rest of the year and then I can deal with anything else over winter