pszikla

Last year the transmission/differential started to make some noise and I'm fairly certain that it is the differential.
Symptoms are lot's of gear noise "off load" (foot off of gas pedal but in gear)
Some gear noise when coasting in neutral.

opinions needed on sensible and least expensive solution..........

1)Change transmission for
a) fully rebuilt
b) take a chance with transmission from junkyard

2)Have transmission stripped down and change ring, pinion and bearings in diff.

Thanks in advance
Pete

1999Porsche911

How about changing the fluid first? Run it on a lift and identify exactly where the noise is coming from? Many noises, like a tooth ache, appear to be coming from one area yet end up being something else. Many times, a dragging brake shoe on the rear drum can transmit noise to under the car.

washington dc porsche

Option 2 Have your tranny rebuilt.

Paul 996

May I suggest working with a reputable shop that can undertake Option2 but with the caveat that open it up and assess what is needed and what it will cost. At that point you can decide if Option 1A is a better move.

Depending on how much/how little is worn/damaged you may be better off just fixing what is broken. But if it is a mess in there just move on.

2cents

pszikla

a friend suggested draining the oil and then putting in fresh oil along with one quart of Lucas heavy duty oil stabilizer to see if this would quiet the gear noise. I realize that that is obviously not a permanent fix, but it might delay the inevitable repair cost until the economy gets better.

Doug Donsbach

I'd be very careful about mixing lubricants like that. You just don't know what happens when the mix gets beaten up by the transmission - it might turn into an aerated mess leaving you with less lubrication than you had before.

Dave!

I remember seeing a demonstration of lucas oil stabilizer at high rpm where the stuff just turned into a dense foam that got flung around everywhere. Apparently this makes things sound smooth but does more harm than good.

I can't be 100% on this because I don't have the link, but I'm pretty sure it came from Bob is the Oil Guy.

Edit: Found it - http://www.bobistheoilguy.com/images/lucas/lucas.htm
It's not a perfectly scientific study but you can get the idea.

pszikla

Thanks guys!
Very interesting demo on that "Bob, the oil guy" site!!
Pete

pszikla

hey everyone!
Just an update................my baby's in with my indy and we crack open the transmission/differential tomorrow.
I'll let you know the damage in a few days!!

p.s.
different subject.........he was rebuilding a 2003 engine from a C4S with a cracked cylinder wall.
We talked IMS mod while my transmission is out and he said that he has HAD ONLY ONE car in with IMS failure in last 3 years. Although I was not encouraged by the cracked cylinder wall, it seems that we mostly mention IMS here and only one makes me feel a lot better!!
This indy is largest in eastern Canada and is extremely busy all of the time.

va122

Dude, PM smsarcheticts he has a GT3 diff he's selling, you can send it to Guard and get upgraded internals or have your shop put the cup clutch pack. You'll never have thought your car could handle like that.