J160 gear oil smell ?????

[Drifty200]

Hi guys , new here but not new to the is200 scene ! 
 

i have been having issues diagnosing the problem I’m about to speak about for a while now and I cannot for the life of me figure it out so please can I borrow some of you’re brain cells for this one ! 
 

did single mass conversion , everything working as it should , a few months go by and all of a sudden I get this gear oil smell and smoke coming into cabin , I get the car onto my hoist and check it out , no visable leaks etc . Another few months go by and I’m driving from Sydney to Brisbane and my gear box blows halfway up ( losing every gear besides 5th ) 

 

I get trailered to Brisbane and I found a new gear box with 152k kms and I changed it over with still the same gear oil smell ??? 
 

keep in mind , fly wheel is good , brand new HD clutch , fly and clutch both excedy , 75w - 90 gear oil used , 2.5 litres straight into gear box and no visable leaks ! 
 

hopefully someone here can solve this problem for me lmao thx for reading guys and gals ! 

[bazzle]

Just some off the cuff thoughts...

Gearbox Breather?

Air leak around floor seal?

Overfull gearbox?

Is it that you can smell?

[Drifty200]

Breather is the only thing I havnt checked just yet ! Otherwise no air leak as I got new shift boot rubbers to stop the smell and smoke ( smoke is gone now ) . I doubt it’s over full gearbox as I was pretty spot on with filling it up and also this smell continued right up until my gearbox blew halfway to Brisbane and it blew because it had a leak and ran dry of oil and yeah it’s gear oil that I can smell no doubt 

[2bling]

Rear gearbox oil seal, the tail shaft could be flicking it on to the exhaust causing smoke and smell, only has to be a drop and burning off it stinks. PS its not the diff pinion seal, does the same thing good luck.

[Drifty200]

Update guys , just parked it up after a hard drive in my garage and thought I’d see where it drips on the ground , I’m yet to get the car up in the air due to back injury but wanting to see what ppl think of it 

 

3 slight drips on ground behind where the AC drips down towards back end , almost exact spot as slave cylinder but I’m not losing fluids at my clutch reservoir / filler ???