Just wanna throw an intro out since im new to this board..

I've had my 996TT for almost a year now. I use this car a secondary "fun" car.. When I first got it at 69k there was an audible whine coming from the transmission at freeway speeds in 6th.. So I changed the fluid and the noise went away. However, about 2k later on the new fluid (Lubo moly 75w-90 GL-5) on decel ONLY in 5th i can hear this whine again. I was doing some reading and some said to check fluid level because 5th is in the top of the trans. So I added about half a quart (about as much as I could get in there) and the whine is still audible in 5th gear decel only.
This is what my drain plug magnet caught on the flush


any ideas? TIA
Here is a pic

 

not unusual to see that type of metal collection . isse it all the time. as for gear whine it could be improper backlash spacing or axle bearing whine

i dont know about this gear oil your using rec. is mobil 1 75/90

 

thanks for the reply

I was thinking about making the switch to Delvac 75/90.. I plan on taking apart the box soon because I have a issue with 1st gear pop out. Slow rolling it goes into gear fine(and stays in on hard accel/decel which leads me to believe the gear itself is fine) However, stopped at a light engaging first its hard to move the collar. Might be a bad syncro.. I did the Detent from G box and it fixed it for a little bit..

But I digress.. Interesting how the noise went away after the flush, but now is back only in 5th on decel.. I dont believe the box has ever been taken apart how does Improper backlash spacing happen?

 

it can happen. 1st gear popout is unusual. if its hard getting into gear its likley a syncro gone bad

 

Would axle bearing whine be present in all gears accel/ decel? How would backlash spacing fall out of tolerance if the trans has never been opened?

thanks again

 

my bet/guess is just worn bearing,.(s) . happens to us ALL "sooner" or "later".

agree of never really heard of 1st popout but who knows, if the synchs rounded enough. anythings possible. GL w it. its gonna have to get opened. its time. sorry to say.

 

Is it common for carrier bearings or pinion bearing to fail? 72k seems young..

Definitely gonna get opened, kinda spit balling to see what others have encountered/ know what to expect

thanks again guys

 

its not uncommon for axle bearings to wear of the car has been lowered without proper drop links camber adjustment etc. it sounds more like a syncro but only way to know is to open the case

 

That makes sense, but in my case if I were to put the clutch in and "coast" the noise would still be apparent if it was the axle bearing(s) right?

This noise is only heard in 5th decel and I can change the "tone" of it through the rpms.. After typing this I am starting to think its the carrier bearing(s)..

 

pinion thrust or both.

here's a bit of info that may help. usually it's the pinion bearing that goes first and whines in any gear, you'll hear it. but more prevalent in higher gears was my experience.

http://rennlist.com/forums/996-turbo...gone-info.html

.http://www.gboxweb.com/996shimtip.html

 

Yeah mine was doing that along with a stripped out 5-6 shifter. I've heard it's the pinion bearing that usually causes that. My pinion bearing was replaced along with some other parts by Brian Copans.

PS is that just some light tint in unique headlights? Looks good. I've been thinking about doing that myself. Can I get a few more pics? Thanks -Wade

 

Thanks for the reply's guys, I got some things to go off of now when I pop open the box.

Ursoboosted Ill snap some pics tomorrow for ya. It is just a tint over the head lights( protects from rock chips/ pitting in the canyons as well as aesthetics)

 

This may be helpful.

https://www.6speedonline.com/forums/...ear-specs.html

Later, Steve

 

I understand that Delvac is recommended by many, but have you looked at the viscosity charts for Delvac? MUCH thicker when cold, causing notchiness in the shifting mechanism. Have researched and am leaning towards Motul 300 75w90 since it is VERY similar in viscosity to the stock fluid and is a GL-5. Motul is high quality full synthetic, so I would presume this would be a good bet. Anyone else have an opinion on this particular fluid? Wish I could but the Shell fluid in 1L containers, but 45 bucks a litre for stock fluid is absurd when you need 6 for the front diff/tranny flush.... Damn!

 

Price a new tranny/diff or two diffs...

My Boxster has nearly 300K miles on its 5-speed and it gets the stuff the dealer gets from PCNA. My Turbo's tranny -- replaced at around 30K miles wtih a factory sourced tranny (selector shaft leak) -- gets the stuff the dealer gets from PCNA and has accumulated around 110K miles. Still shifts just fine and makes no noise whatever.

It is not worth the risk to me to use my cars as test mules to find cheaper alternatives to the factory recommended fluids.

Besides, sometimes I get the fluid at a discount, if the dealer has some left over from warranty work.