Oddjob

This is all that is listed in the Service Information document for the 997 Cups for torque specs:




There are some critical nuts/bolts not listed here. Diff cover (same as casing nut?), shaft/gear mounting plate, slave cylinder, bell to engine case, etc.

Are there other more detailed service documents available, giving more information and torque specs?

ORBIT

Hello , What do you want to know about the gearbox? I have been building these since the first sequential in the 2004 996 RSR. Happy to share the information. I always have a few here for rebuild. Not a complicated gearbox to work on but there are a few tools you need. One of the biggest problems is when third gear breaks.
Rodger@orbitracing.com

Oddjob

Thanks Rodger,

Hopefully no broken gears...

I've got a rough 4-5th shift, going both up and down. It occasionally won't upshift into 5th, and also at times won't downshift into 4th - kicks back and stays in the current gear. Problem is only between 4 &5th, no issues with any of the other gear changes. The issue is getting worse, more frequent, and gets worse when hot (later in the race/session). Not sure if it just needs the dog rings replaced, or other issues (maybe the selector barrel?). Also, the neutral/reverse lock doesn't work - it doesn't lock, stuck in the open position. Want to figure out what's not right there.

So planning to open up to inspect.

Also, trans came with a short 4th gear 1.474, and I want to return it to the stock 1.400 ratio.

Not intending on replacing bearings or the R/P.

Looks like there is a tool for reinstalling reverse gear & slider - references it in the service document but no pictures, so not clear what it is or does. And the cut away housing needs to be installed when adjusting the reverse selector fork?

Any other special tools required to unstack and reassemble the shafts?

No specific sealant for the casing flanges is called out in the manual, says "sealing compound". I'm assuming something like a loctite 574 is ok?

Oddjob

Belated follow up to this.

I'm posting some pics of the teardown for anyone interested.

And I want to give a big thanks to Rodger at Orbit for reaching out on this. We had a long phone call talking thru some the specifics of this transmission. His time and insight were invaluable. And also Matt at Guard for offering his support and sending out parts same day. Awesome service.

Car was back on track a week and half ago, and the transmission worked, no explosions. In the end, replacing the 5th gear dog ring and the 5-6 selector/claw collar fixed my 4-5th shifting issue.


















5th, 6th & reverse















1st-4th gear sets



Existing Guard LSD


'



5th Gear Dog Ring



Replacing existing 1.474 Holinger 4th gear with taller stock ratio 1.400 Guard set.