New 996 Owner - Synchro Ring DIY

Hi Everyone, Last week I brought home a 105k mile 996 (1999 911)! I�ll post more pictures later today as my phone is currently having issues uploading photos. I bought the car sight unseen, near Los Angeles, knowing it had some mechanical issues and little (no) maintenance history. I paid a very reasonable price due to the nature of the problems and lack of docs, but, now the fun begins! Some major issues with the car: - 3rd gear mild occasional grinding - 4th gear issue (bad grinding). The shifter allows entry into 4th with the clutch pedal depressed. With the shifter in 4th, I try to release the clutch pedal and as I do so, grinding starts, the gear pops out. I basically skip to 5th gear when driving. Some minor service items that I will attend to as well: -Brakes squeak occasionally (front pad replacement needed) -Parking brake needs too much force to engage. -Rattle coming from behind dash + foam bits in the cabin air vents -Exhaust seems low, likely need new motor mounts -Deferred maintenance... IMS bearing change, chain guides etc etc I haven't been under the car yet, but, the car runs well, good power, turns well. Really a high quality example - I never understood why the 996 got so much flak it is such a solid car. So the near immediate dilemma is that I'm torn between getting a used trans, or, doing the synchro replacement myself. Can you guys provide some info on the cost & difficulty in doing a DIY synchro replacement (assuming I just need to replace the 3rd and 4th)? I consider myself a semi-competent at-home Porsche mechanic. I had a 1978 911 many years back and I currently own a 91' 928 .. I have done quite a bit of work on it (torque tube rebuild, intake refresh, etc etc) so I'm thinking a synchro job is something I can tackle. Any advice, resources etc would be really nice. Thank you in advance. Mike

Hmmm, were the two boys in there when you opened the Frunk? As for the syncro question, there are a couple recent threads dealing with Tranny issues. If you're a competent mechanic with some experience in manual transmissions it may not be out of the question assuming you've got the proper tools and maybe a shop press...

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LOL ... no, they're mine. They wanted to inspect the hood to make sure that there was no engine ... Confirmed. I found these threads the other day after some digging: https://rennlist.com/forums/996-foru...ent-diy-2.html https://rennlist.com/forums/996-foru...y-project.html Are there some others? I'm also thinking of getting the shop manual, but, does it address synchro replacement in detail? Mike

Ha! They look like they're loving it!!! Yup, those are the threads! I have no idea re: the shop manual, but I would imagine that everything is in there - The real Porsche maunal(s) cost well over $1k and probably closer to 2k. The Bentley manual is supposed to be very good, but I'm not sure how far they get into the transmission(s). Good luck - and if you wind up doing the work yourself, please document it!

Since the tail pipes are low first, change the engine mounts and see if the shifting improves. Sounds strange to a new 996 owner but there is a direct relation to poor shifting and sagging mounts.

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Thanks - got new Rein mounts on order earlier in the week and they should be here today.

Unless you have some very good shop tools and a massive press, I would not tackle this job DIY. Has been done DIY but a lot of problems crop up. This is epic https://rennlist.com/forums/996-foru...ement-diy.html I would send it off to GBox for a synchro refresh http://www.gboxweb.com/index.html

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Thanks for the suggestion! Tools and presses aren't a problem, its mostly a time issue. I like doing the work, and, would rather do it myself. Swapping a trans is quicker. Can you provide some threads/posts where "a lot of problems crop up"? I'd like to see what they are. Thanks, Mike

Read the thread I posted. And wow...you have a 30 ton press at your disposal? See that thread for some of the tips and problems.

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Thanks, that's the thread I originally posted. I have access to a machine/engineering shop with a variety of presses and tools. I don't know what the ratings on this shops various presses are but I'm fairly confident they have one that can handle this - they rebuild airplane engines as their main business. Mike

Finally got under the car today. First thing I saw is that the engine area appears to be free of wet oil. There are spots where it looks like some seals need to be replaced, but, overall, nothing too bad. At the transmission though - different story. It looks like gear oil is coming out in a fairly healthy manner from several areas. In fact, one of gear linkages looks fairly soaked. So the trans is likely low on oil, and, in need of new seals. Does the oil on the linkage indicate a problem with the actual linkage, or, inside the trans? Next step is to figure out if the linkage is healthy... time to do some research on how to test linkage... any advice here would be welcome Why is it soaked at the linkage and not at the housing? Another shot...

My 928 has a new partner

Iv'e got one of each too!

Hi Everyone, So, after some deliberation, I decided to source a low mileage used transmission. It should be arriving late next week. I'll be taking the original one apart to see what needs to be fixed, but, I'd rather be able to drive the car while I rebuild so I went ahead and got a used one from what I hope is a reputable source. Removed the transmission yesterday. Took about 3.5 hours - its not that bad of a job. Last year I did a torque tube rebuild on my 928 where I had to drop the trans and that was a more difficult job... the 928 trans drop takes maybe about twice as long as compared to the 996. What sucks on the 996, is that even with dropping the engine onto the cross-member, that top transmission bolt is a real pain-in-the .... Some photos below; I'm going to figure out what I need to replace and what I don't. I'd rather not replace stuff that still has life left as I like doing these jobs and would rather not waste stuff. Anyhow, how does this clutch look? I'm not sure what a worn versus good 996 clutch should look like... Also, I have a parts list going on pelican - I would be interested in what else needs to be replaced: Part Number: 997-101-212-01-M17 Price: $13.75 Qty: 1 Description: Flywheel Seal, 996 Carrera 2/4 (1999-04) Part Number: PEL-TOL-T136 Price: $8.85 Qty: 1 Description: Clutch Alignment Tool Part Number: 999-073-092-02-M260 Price: $1.75 Qty: 8 Description: Flywheel Bolt - Crankshaft to Flywheel (10 X 50 mm) Part Number: 900-067-131-03-M260 Price: $0.50 Qty: 6 Description: Bolt - Flywheel to Clutch Pressure Plate (8 X 16 mm) Part Number: 996-116-087-01-M100 Price: $42.75 Qty: 1 Description: Guide Tube for Clutch Release Bearing Brand: Genuine Porsche Part Number: 996-301-805-00-M204 Price: $7.25 Qty: 1 Description: Main Shaft Seal Brand: Kaco Part Number: 012-141-751-C-M1002 Price: $2.75 Qty: 1 Description: Pivot Piece for Clutch Release Lever Brand: Genuine Part Number: 996-116-743-00-M100 Price: $2.50 Qty: 1 Description: Sealing Washer for Clutch Release Lever Part Number: 996-116-080-04-M38 Price: $101.50 Qty: 1 Description: Clutch Release Bearing Brand: Sachs Part Number: 4200-080-050-M38 Price: $7.50 Qty: 1 Description: Clutch Disc Spline Grease - SACHS High Performance Part Number: 996-116-741-00-M100 Price: $10.75 Qty: 1 Description: Retaining Spring for Clutch Release Lever Pivot Trans after some cleaning. Is this clutch too far gone?

That clutch looks about half worn, maybe a little more. Since you do all your work, reinstalling it is not a terrible choice. I would at least reline the disk or get a new one and install a new release bearing. The pressure plate looks normal for a used clutch. Too far is when the rivets dig into the flywheel or pressure plate. By the way, a release bearing from a '97 Audi A4 is the same as the one for the 996 (I've used it on my own car) but at a fraction of the cost (doesn't have the Porsche badge premium) Next time if you need to remove the torque tube on the 928, the transmission doesn't need to come out, Just disconnect the transmission mounts and push the transmission back a few inches and the front will clear the bell housing. The parking brake cables will need to be disconnected from the rear cross member too.

Do yourself a favor and source parts from someone other than Pelican - you'll probably save a few hundred $$. www.warehouse33.com is a good one (though the site navigation kind of sucks...) and he gives Rennlist users 10% discount. There are plenty of others out there as well - Pelican is convenient, but some of the prices are just silly. Good luck

928sRus is a vendor that can get ANY Porsche part for ANY model. They specialize in 928s but they can get others at a much better price than pretty much any other Porsche parts vendor. Roger the owner is a very straight up guy, as honest as they come, highly respected in the 928 community. He is an old fashioned vendor so their website needs major overhaul but don't let that scare you. Send him an email with the parts you need or just simply call him.

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Thanks! I'm on the fence with the clutch replacement, but, I'm leaning towards replacement. Really cool tip on the release bearing! I just bought one from LuK for < $20. Thank You! The TT job was interesting as I had the tapered driver shaft (which, apparently is longer and weaker), and, when I pushed the trans back, the shaft at the front never even came close to coming out of the bell housing .Then I tried to un-bolt the front bell housing, but, I couldn't get at that top, drivers side, bolt. So, the path of least resistance was drop the trans. I'm still thinking of a way to get at that front bell housing bolt LOL.

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Will do! I use pelican for the project tutorials and for their project list tracking. I tend to spread my money around to a few vendors as well.

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Thanks for this as well! I called Roger a bunch when I was going through my 928. Really really helpful, can't say enough good things. I didn't know he provides 911 stuff... I'll start shopping with him as well for my 911 needs. Mike

Got a look at the IMS and RMS and then Cleaning and more cleaning today. The RMS was leaking (thin bead of wetness around the seal) so I pulled it and will replace. The IMS area looked ok - nothing wet. The oil from the RMS spread out all over but there were no wet spots near the IMS. I have a few days to decide what to do about the IMS bearing, but as of today, I leaning towards leaving it alone. In general, I'm torn on this IMS thing... I'd rather replace it with a double row part, but the only reasonable alternative (cost wise) is the pelican parts kit with a single row bearing. I don't think a bearing needs to be > $100 at the most. Not sure what to do? Suggestions welcome... Also, to the right and above the trans is this thingy below - its spewing some oil and I'm not sure what it is. What is it, and what do I need to fix?

Edit: See following post - I'd rather not focus on the IMS solutions here, but, I will be replacing it with what I believe is best. Hi Everyone, After thinking about this IMS thing more and more, I've decided to replace the IMS bearing. But, I am going to try source my own double-row bearing. If that proves difficult, I will purchase the pelican parts IMS kit. So I went looking for a suitable bearing with the following requirements: - 5204 2rs (sealed) - Double Row - Steel cage (temperature 150C) - ABEC 3 (or higher) - is this really needed? Is ABEC 1 ok? - 10000 rpms - dynamic load rating of 5000 lbs Does anyone know any sources? I'm found the following on Amazon: Amazon Amazon Not sure about the above... Getting quotes in from other manufacturers as well. Mike

Beware letting this become yet another IMSB thread which will derail your thoughtful Postings. We have been deep into the diy IMSB story many times. It does not always end well because there is more to the issue than the spec of the bearing. As a bench mark I suggest you consider the kits offered by RND. That story will end well. http://rndengines.com/roller-bearing-ims-retrofit-kit/

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Yes! You're right and thanks - no more IMS talk here and I will solve this and put in the solution that I think is best. In any case, this car will have a new IMS bearing installed this week. From this point forward, I will focus on transmission issues Regards, Mike

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Thank you for the praise, I agree the current website does suck but I'm fixing that right now with a totally brand new website. I'm testing the new one, just trying to get all the bugs fixed on it before it goes live. -Jason

Jason, While you are in there fixing the Warehouse 33 web site, Here's a problem to fix. I bought some parts from Warehouse 33 over the weekend . When I try to connect to your site via Firefox ,I am blocked ! "The owner of www.warehouse33auto.com has configured their website improperly. To protect your information from being stolen, Firefox has not connected to this website." This may just cut into your sales?

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Hmmm that's strange I just tested it on Firefox on my PC and seems to work for me. Maybe you have a Warehouse 33 blocker? Was it from an MAC or PC? The new website will be a completely new site and on Rackspace servers so speed should be better too. And thank you for your business, I think your parts will arrive tomorrow. -Jason

Blazing Fast delivery, the correct parts and 10% off too .Thank you Jason !

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No thank you! -Jason

Hi All, Made some progress on several fronts. - New AOS installed. This job wasn't fun. Even from the transmission tunnel, I struggled to get those crimp-clamps off. Took a couple hours, but, new AOS! - Replaced the IMS bearing. This job wasn't too bad. I took some extra time as I made all my own tools. Pulling the bearing out was tough. It was the double row and it took a lot of wrench force to get it out. Managed to slip the wrench when I was pulling it and got a nice dent in my nose Pictures below. New AOS, man this was a pain... Handmade cam locks. $5 of 4mm metal bar and 30 minutes with the jigsaw. Hardware store bearing puller. A 2" coupler and about $12 worth of solid bolts/washers. Dual row bearing came out with seals intact. Seemed to be in good shape. Bearings all looked good... not sure if I replaced a perfectly good part, but, its nice to have piece of mind. All sealed up with. Some of you may recognize where I got this stuff

Now I am ready to focus on why I started this project in the first place. The transmisson. I've never opened a 911 trans, so I'm not really sure what I'm looking at. Below are photos and I'd much appreciate any helpful descriptions. Some things I noticed: - Not a lot of fluid in the case < 1 quart for sure. - Very very silvery colored fluid. - The magnet was caked in slivery metal. I took as many photos as I thought would be useful, but, I'm having a hard time telling what's worn... the symptoms were 4th making an awful racket when I engaged the clutch. Which is 4th gear below, and, how do I tell if something is wrong? Trans opened up. Very silvery fluid - not sure what to make of this... gears and more gears...

If you are above avg DIY and only replacing the 3rd 4th syncro you can do the job without the heavy press. I just completed the same job on my race trans and have repaired many. Disassembly is not hard, But take pictures of the shift fork layout beforehand. Start by removing all the shift forks by removing the roll pins and the lockout plate. Remove all the retaining bolts on the drive plate. To remove the gear stacks heat the case by the pinion bearing and with a brass hammer drive the gear stacks out as a unit by "Tapping, Hammering" in the pinion gear and input shaft Its slow work but it will come out, Heat is your friend. As far as I know, no one yet has devised a tool to get the front input shaft bearing off and it has to come off to get the input shaft separated from the drive plate. I always sacrifice the bearing by cutting off the outer race with a cutoff wheel. After the stacks are separated you can press the inner race, spacer and 3/4 syncro hub off by pressing from the 4th gear with a bearing splitter. Reverse order to reassemble.

OP, There are 2 or 3 epic threads on this task-one recent . That's all. Did you find them? The skills and knowledge required are way beyond the average diy guy. It would be wonderful if someone would video dgmark next time he rebuilds a transmission.AS time & miles accumulate ,the need for this work will grow.

As an add on 3/4 is the 1st gear set in the input shaft closest to the ring gear housing, Is your noise only when the gear is engaged or also in neutral?

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dgmark, Thanks! I really appreciate you helping me with this really good info. I'm going to need all the help I can get This job will definitely push my skill set, but, that's the point! How else does one build-up a skill set other than by doing? Documenting the shift fork layout now and will remove the lockout plate tonight. Regards, Mike

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No noises in neutral. With the clutch pedal all the way in, I can get it into 4th, then, when I start letting off the clutch pedal (just barely starting to grip), the grinding gets pretty bad and the gear pops out.

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Hi, Yes, I saw those threads, they're quite good. There's even a pretty good video I found (not for a 996 trans, rather for a 930): You Tube Thanks, Mike

If it is not holding 4th gear it is either not engaging fully or not holding after engagement. My guess would be a problem with the Syncro hub as the synco ( Brass Portion) is out of the equation after the gear is engaged. Your probably going to have to replace the hub assembly but also change the 3rd fourth syncro rings when you are in there. Take a good look at the dog teeth attached to the gear and make shure none are missing, from what I can see in your picture they look good. The hub is about $265. Syncros $140 each and the bearing about 275.

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Thanks dgmark, When you write "hub assembly", do you mean the part that is sandwiched by the 3rd and 4th syncro rings? http://www.autohausaz.com/search/pro...ysCxoCMLjw_wcB Is 996 304 041 01 the part number the I'd be looking into? Mike

Start looking really closely at the shifting forks too. Compare them to each other and from one side to the other too. The one/s that look different will be the worn ones BUT you have a severely worn bearing in there that you haven't yet found. It will be obvious when you see it. Check the bearing races that stayed in the case too. The one that made the lots of noise will be in a really bad shape. I've done a few transmissions before but not a 996 one yet. However, they all more or less work the same way.