I recently bought an 04 6mt with no engine and good body to swap out my engine/trans from my 06 with a banged up body into it. After the swap i've got noises coming from my trans that weren't there before. It doesn't make the sound right away, it seems to take about 20-30 minutes of driving, and once you put it in reverse it stops for some time(or at least limits the sound enough to where its not audible enough to confirm). Also, while i can't make a direct connection to this yet, it seems like it can be triggered by a long hard right hand corner. The sound seems to be worse in forward facing gears as well, and the tone changes from gear to gear. I wasn't able to upload the video due to file type and can't convert while i'm at work, but here is a google link to the video i took of it happening, i think it gets the sound of what's going on fairly well. Trans noises (https://drive.google.com/file/d/1Xhm...ew?usp=sharing)

The transmission does have 145k miles(mostly highway), but never gave this issue before and was not even disconnected from the engine during the swap. The ONLY things that changed during the swap was a short throw shifter and replacing fluid with Redline GL4 75-85 (which i did confirm after hearing the sound is at proper level). I can't really wrap my head around how anything could have changed/went back moving the the transmission(while connected to the engine) 6 feet to the left... This swap has ran me dry for both energy and money and really hoping there's something happening that i'm overlooking that doesn't require replacing the trans.

Also engine is bone stock, fyi.

If anyone has any thoughts of things to try or certain information i missed that i need to gather for better troubleshooting let me know. Thanks to anyone that chimes in.

 

First check the fluid level, remember the vehicle needs to be LEVEL when checking the transmission, if you're using jackstands it needs to be up on all 4. If level looks good then drain the gear oil out into a very clean container and inspect it for any shavings, that way you can pump it back in when you're done if it's good.

Everything feels like it's shifting fine though?

 

So the first thing i checked was fluid level when i heard the sound, it was overfilled so i let it flow out of the fill plug until it stopped. Was jacked up on all 4 and as level as it could get without using a leveler. 30min test drive showed the same results.

Shifting feels absolutely normal.

 

Firstly gearboxes are noisy, I don't necessarily know that there's anything WRONG with it. The only sound I'd be concerned with at all is the "ticking" in 3rd gear, I would also jack up the rear of the vehicle and spin the wheels by hand to see if there's any noise associated with the axle/driveshaft spinning.

Can you hear it once the weather seal and console are reinstalled?

 

Yes you can definitely hear it through when everything is installed, just pulled it all to get better audio from it. It's not just a noisy gearbox sound, the video from my phone likely doesn't relay how loud it gets. The ticking in 3rd is also heard in all other gears (sans 6th), it just changes tone with each gear, forward gears being louder with 3rd being the loudest. When its at its worst i can feel it through the shifter as well, not jarring, but there's a noticeable vibration that's felt.

 

And this was your existing transmission that did not have this problem BEFORE the new engine correct?

 

That is correct, it was my daily for the last 6 years and worked perfectly. Did not disconnect from engine when doing the swap, pulled engine and trans together and slid back in together.