Changing g50 Tranny Oil - Plug locations

glee911 · 03-02-2004, 06:53 PM

I am attempting my first transmission oil change on my '87 Carrera. Can someone help with the location of the drain plug? I noticed a 17mm drain plug on the bottom on the the car near the back of the engine - is this the correct one. In Wanye's book he mentioned a 19mm drain plug?

Also where exactly is the fill plug. Didn't really notice anything on the left side of the transmission. Thanks everyone.

Eric Coffey · 03-02-2004, 10:37 PM

Hmmmm, the fill and drain plugs should both be 10mm (requiring a 10mm male allen wrench) for your G50. If you are sure the drain plug is 17mm, it was probably replaced with an earlier one at some point. Anyhow, the fill plug is located high up on the left side. Just crawl under there with a light, you'll see it. access is a little cramped, but you should be able to get a 1/2 drive up there with a 2-3" extension and a 10mm allen socket. As always, remove/loosen the fill plug first before you drain it. That will insure you are not stuck with a empty, un-fill-able gearbox. Have fun!

glee911 · 03-03-2004, 04:25 AM

Thanks Eric. Time for a closer look.

Wavey · 03-03-2004, 04:48 AM

Yep, definitely loosen the fill plug first, they can be a real bear, to the point where you'll be glad to pay someone else to do it. I nearly broke my elbow on the shop floor (seriously) when mine finally let go.

KTL · 03-03-2004, 05:44 AM

Quote:

Originally posted by Wavey
...............I nearly broke my elbow on the shop floor (seriously) when mine finally let go.

Same here. Smacked my elbow on the engine harder than any time I can remember. Seriously thought I broke it.

So when you reinstall the fill plug, torque it to the recommended spec. with a torque wrench. Don't gorilla tighten it. I think the spec. is 30 lb-ft.

Clearance was kinda tight and I had to resort to a 10mm hex key. If you choose to go that route, i'd suggest slipping a piece of pipe over the key to get a little extra leverage. But don't beat on it. Trans. case is aluminum alloy and you could damage the female threads in the case?

real550A · real550A's Garage

Is it just me, or is 30 ft/lbs an astronomical torque on an inanimate fill plug?
With 35 years of truck, racecar, airplane, and heavy equipment experience, I've never had one fall out after tightening finger tight and turning 1/2 turn (or so) with a wrench. (ie. 7-10 lbs.)
There is no reason I can see for that much torque, and they come out easier the next time.

KTL · 03-03-2004, 06:22 AM

I was going by memory and it turns out the 30 I mentioned is the Nm spec., not lb-ft. So the correct value is 22 lb-ft according to the Carrera/US Turbo spec. book. Still not astronomical though........

Thanks for the correction.

993.986. · 03-03-2004, 07:39 AM

On my 87 there were some hoses that run right by the fill plug, I used a 4" extension with a 10mm hex socket to get around those with no problem. I used a torque wrench to button things up and was surprised at how fast it clicked, I would have probably over-tightened for sure without it. Good luck
BTW when I was down there I noticed an opening in the trans case and I could see what looks like the edge of the flywheel (teeth), is that supposed to be there?

kepperly · kepperly's Garage

I can see mine also but I,ve been afraid to ask!

Keith Epperly 87 slant nose turbo look carrera cabriolet

real550A · real550A's Garage

You're right, Kevin.
Astronomical might have been the wrong word. I just tend to not over tighten fill plugs for the reasons mentioned above. They're usually not subjected to high pressures or excessive vibrations that would cause them to "walk" out.

KTL · 03-03-2004, 09:05 AM

Understood Mike. I'm glad there's guys like you out there that know the "feel" of tightness. Seems that all the used cars i've owned have been previously serviced by Hercules and gorillas. I guess I can't complain too much though. As a kid, I was known to overtighten everything I could put a tool on.

Lester & Keith,

That opening is there on mine too. Probably a good thing to have because that hole could alert you to a leaky flywheel seal pretty quickly. There's actually a few moreplaces on the trans. where you can get a look inside the bellhousing. One place is up top where a rectangular rubber cap (about 1-1/2" x 3") covers an inspection hole. #26 below

HarryD · 10:19 AM

To change the direction of this thread a bit: What is the view on using a bit of anti-seize on the plugs to make them easier to remove next time?