I noticed a new leak under the car, strawberry colored fluid was slowly dripping out of this skinny tube connecting to the transmission. It appears that the fastener can be hand tightened, but should I worry about a rotten o-ring inside or something?

 

That's your speedometer cable.

 

The driven gear housing has an outer and an inner seal. The silver, bullet-shaped piece in the following link is what you need:

http://www.transmissioncenter.net/sp...____va.htm#350

Also check post #1 of the following:

https://www.thirdgen.org/forums/tran...ve-driven.html

JamesC

 

Thanks for the links and clarification.

So is this new gear housing installed via the leaky end, i.e. unscrew tube and remove old one and replace or do I have to remove shift boot and take everything out from above?

 

Unscrew the cable from the housing as in the above pic. Remove the small bolt and clip that hold the housing in place, then gently pry the housing out. You'll lose some fluid. Check at the bottom of post #1 of the link I posted above. Douse the new housing in trans fluid, carefully transfer the old gear into the new housing so as to not tear the internal seal and slap everything back together.

JamesC

 

Excellent, my last obvious silly question is, since I'm already seeing reddish fluid coming out, this particular transmission uses ATF and not gear oil due to the color. So is Dexron II or equivalent alright to use when dousing the new housing prior to installation?

 

Now there's a can of worms:

https://www.thirdgen.org/forums/tran...ything-we.html

I use Mobil 1 ATF in my 85.

JamesC

 

Lube for the T5 is the subject of many heated debates... Some documents suggest gear oil for non-world class T5's, and ATF for world class T5's. Yet other documentation suggests ATF for both. If you drain the fluid (I wouldn't) just take note if it's ATF or gear oil and replace it with the same. I ran Mobil 1 synthetic gear oil in my NWC T5, and I've run cheap ATF in my world class T5's. I noticed a considerable improvement by running Pennzoil Synchromesh in the world class T5's in the Mustangs. The synthetics make them shift like butter.

I'd pull the speedometer gear adapter out of the trans and inspect the O-ring. It shouldn't leak much if any fluid, but I'd put a drain pan under there just in case. If the O-ring is bad, pick up a new one from the parts store. You may not need to replace the adapter.

The spiral groove cut into the speedometer gear stem is supposed to carry any errant fluid BACK inside the transmission while keeping the parts lubricated. While you've got it apart you might want to clean out the groove if it's not clean and clear. If the groove is blocked it won't do it's job. All that said, an occasional drip from the speedometer cable isn't the end of the world, and I would consider it completely normal. Judging from the fact that the aluminum shield on the cable is clean and shiny, it's not leaking very bad.

 

Finally got around to replacing the driven gear, and leak has stopped. The old gear had a rotten O ring, and gummy dirt stuck inside. Thanks for the assistance!