Newly rebuilt 46RE auto trans. built myself. about 4k miles since rebuild has been running super strong. altho im Starting to get a pretty noticeable whine coming from 2nd and 3rd driving gears. The clearest way i can explain this is it sounds like theres a lack of fluid flow. Heres why. Lets say im doing 50mph the whine is very noticable. however if i switch the gear shift lever to the neutral position you hear the whine go away and it starts to sound like fluid being pushed thru trans - dampening the gear noise. i could be wrong but does anyone know why this would happen? at slow speeds i can hear what sounds like an unbalanced tire. altho the tire isnt the source in this case. it makes a noise per rotation of the tire. as if something was rubbing against a surface of something else in one particular spot. kind of like that noise you hear when your brake pads are being worn down to the metal. I dont know how else to describe it. but anyways as my speed increases so does the noise. at low speeds 5-10 mph its very quiet almost not noticable. but up in 2nd 3rd gear increasing speeds the noise goes from a low pitch scrape to a medium pitched whine. i can try to upload a video but cant be promised.

thanks for any tips in advance.

 

Might be tempted to drop the pan, and see what's on the magnet......

 

Are you sure it's the tranny and not the pinion bearing back on the rear axle?

 

pionion bearing on rear axle? It sounds like its coming from the Torque Converter where engine meets transmission. i dropped the pan and found the magnet had a thick ammount of molecular metal shavings. nothing too big. so i cleaned it and the pan. but i also just rebuilt this about 5k miles ago so i assume the shavings could have just contiued flushing out of the small areas it was trapped from before. im not getting any strange shifting, it shifts fast and smooth. i re ajusted my bands and it still whines. what should i be checking for on the pinion bearing at the rear axle? is that part if the back of the transmission or is it accesable without dropping trans again?

 

is this what youre refering to as the Rear differential ? if so, i think the fluiid has never been changed. is it worth throwing a new one in there or just changing the oil?

 

Change the fluid. If it ain't broke, don't fix it. Check for play while you have it up on stands.

 

come to think of it I've been reading some other threads on here and I'm thinking my T/C blew up. At one point during the first 100 miles of rebuild i had some bad shuttering. that smoothed out after fluid started to flow ( most likely due to eliminating that stock check line with the ball & spring) anyway. so no more shuttering but the whining noise comes from the bellhousing. what would cause a new TC to blow up so fast? I found copious amounts of small metal shavings on the magnet. I bought a heavy duty T/C from Advanced auto parts. it was very heavy and much thicker than the one I pulled out while rebuilding. what's the next step I should ensue? i imagine ill probably have to take my exhaust off, drop transmission and replace the brand new T/C with less than 4k on it. I really don't recall hearing this noise in the first 1k miles. just sucks to think i have to drop this thing again and screw with more heavy parts and containers of trans fluid. filters and all that.

another question though, that's got me thinking. - This van will push 100 mph strong and healthy. no slipping of gears and has very smooth shifts. how could an exploded TC support all that torque and stay working? the noise literally vanishes! with the gear in " neutral " position even with the fact that i am traveling at 60-70 mph.... as soon as I put it back in drive gear it starts whining. i also noticed that the noise is dampened with strong acceleration. from 20-50mph. even from 50-70. strong acceleration will dampen the noise. is this in indicator that my TC may in fact be fine but not getting enough fluid ? then again i cant explain the metal shavings in my pan on magnet either... hmmm.

also what about the converter bolts to flex plate? I feel like when installing them last time they were very tough to screw in vs a normal bolt. is this normal? i hope i didnt rethread them at an angle. i backed them out multiple times and tried finding that " better fit " but with each attempt they were still very tight like the thread size wasn't equal to the bolts being used or something like that. either way they went in and its holding up. guess ill find out soon when i drop it.

MY rear differential seems fine too. i gave it a good solid wiggle from all angles and there is zero play.

 

When did you find the metal shavings? Before or after the rebuild?

 

heres a video i uploaded on youtube. hit a few bumps and have some fishing poles rattling so ignore those loud noises. the main noise im trying to get across is that medium pitch whine that comes in at about 20mph. i also take the car from drive to neutral while still traveling 35mph. notice how the noise pretty much vanishes and then comes back when put back into Drive gear.

 

Sounds like a failing bearing, or a band that is too tight.