850 transmission mystery noise Topic is solved

snugani · Post by **snugani** » 28 Apr 2026, 19:59

So lately after finally fixing all the things that were making noise on my wagon (muffler, extremely loud fuel pump) etc. I've now noticed a slightly audible whine coming from what I believe is the transmission.

I never paid any attention before because I couldn't hear much over all the other noise, but you can only really hear it with the radio off and the vents off accelerating from a stop. It does change in pitch with the engine, but it doesn't get any louder. I only first noticed it when I had all the windows down and was actively listening for my axle clicking.

I've already done a couple of drain and fills and plan on doing more. It drives and shifts very smoothly for 120k. Now it's driving me crazy because I don't know if it's always made this noise or if it’s a sign of impending doom. If any of you can tell me if this is a normal noise it would be much appreciated

Post by **scot850** » 28 Apr 2026, 23:01

Check the RH front axle carrier bearing has not gone bad on you.

Neil.

snugani · Post by **snugani** » 29 Apr 2026, 05:59

I haven't thought of the carrier bearing, I'll check it. If this noise turns out to be the trans though, is it normal or should I be preparing for some failure in the future?

Post by **scot850** » 29 Apr 2026, 06:47

It is possible. When was the trans last given an oil change?

Neil.

snugani · Post by **snugani** » 29 Apr 2026, 07:13

About 15k miles ago, it looks pretty healthy, a slightly darker red. I'm actually doing another drain and fill today after I change my driver side axle and the seal. The noise is faint, but audible when I listen for it

snugani · Post by **snugani** » 08 May 2026, 11:38

Does anyone have a similar noise? Still hearing it, but it’s not getting any louder. It is present in first and second, until it’s drowned out by engine and road noise. Only really noticeable with radio/fans off

Post by **jreed** » 09 May 2026, 06:29

It's hard to tell from the description what it sounds like. Could you upload an audio or video of the sound?

Post by **Clemens** » 12 May 2026, 22:51

1st gear was a bit whiny on both of my AT 850ies.
The smoothly shifting, frequently drained and refilled AT in my R blew up one spring morning without a warning at 175.000 miles.
You never know what these blackboxes will do next.

snugani · Post by **snugani** » 27 May 2026, 16:20

Here is a video I got of the sound. Sorry for the late reply

Post by **jreed** » 28 May 2026, 05:41

Got it. It does sound like a high pitched whine from the engine or transmission, even when the wheels aren't turning.