Popping out of first gear

Mostly from a cold start but last summer my 99 cab started to have the shifter pop out of first gear. At the lights when I give a bit of gas and let the clutch out it would almost bang out to N. I even started to ensure I went from second gear to first when stopped to ensure I was engaging first gear and the difference from when it happened to didn�t happen was not noticible in how the shifter felt being in the right place. Didn�t happen all the time, but then more and more often. Parked it for the winter (love Canada!) and now at shop for repair. They are saying syncros and transmission work. Last year I had the shop change my parking brake sensor as the top wasn�t closing without the sensor showing the e brake engaged and thought it might be the cables that needed to be accessed during the sensor change may have been adjusted inadvertently but they say as its difficult to get into first gear, this is not the issue. Its the expensive tranny fix. Thoughts? Have had the car for 8 years, no major issues. Thanks!

Sounds like syncros to me. I think the GBox 2nd gear popout detent fix can also fix occasional 1st gear popout, but if it is popping out all the time, I think it won't.

It’s not all the time, still occasional but that it is happening at all is concerning to me. I was thinking that the linkage cables might be out of whack also.

I bought a cab 996 for $8K two years ago to flip that had the exact symptoms....I had read that sometimes just changing the tranny oil with Porsche oil solves that problem but it didn't in my case. I ended up buying a used transmission and replaced the IMS with LN and sold the car at a profit still. I guess my point is....likely you will need to fix tranny. YOu can have GBOX rebuild and you don't have to worry about it EVER or by a used tranny for 1/3 the price and likely wont have to worry about it for 3 years.

This happened to me a few times after I swapped in a short shifter, just like you described. I pulled off the shifter boot and my C-clip had popped out of my linkage leaving only about a 1/3 of it still in the groove. I put everything back together and went through it and snugged it all back down and it hasn't popped out again. Just sharing my incident. Brian

Also replace the trans bushing mount. Its been known to cause issues with first gear shift. I doubt its the issue in this case but a lot cheaper then a rebuild.

I was having occasional first gear pop-out issues several months ago. The G-Box detent fixed it. I was skeptical, but considering the price of a used transmission and all the labor involved, I figured it was worth a shot. First and second gear use the same detent, so the pop-out problem can occur for either gear. Second gear seems to be more common, but on my car it was first gear. In either case, the general consensus is to install the detent before excessive damage develops. Its worth a try, as they are relatively cheap. Follow this thread for detailed instructions. Good luck. Address this NOW before you damage the trans. Scroll all the way through. I added a few photo details at the end of the thread that will be helpful in accessing it. https://rennlist.com/forums/996-foru...ial-diy-2.html

I know it sounds strange but have you replaced the motor mounts? That actually helped my shifting and 1st gear pop out a good bit. It might not help but it's a cheap (from rockauto) and easy replacement that is probably worth doing anyway if you haven't yet. You might be surprised how much it helps.

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I went this route as well, replacing both the motor mounts and transmission mount prior to trying the G-BOX detent in the hopes that the pop-out was resulting from excessive play at the mounts. The mount replacement did reduce the pop-out issue, but it was still happening at least once a week. Installing the G-BOX detent eliminated the pop-out issue; at least in my case. Good luck.

My gut tells me that things are lined up close to the limit on the 1st gear side. Do you have problems with 3rd and 6th? I�d start with a baseline to eliminate the simple stuff first to make sure everything is set up correctly: 1) make sure the cables are properly and rigidly attached at the shifter end and the transmission end 2) align the shifter (green alignment tool is cheap ~$5) 3) make sure the cables and ends are undamaged (I had a 996 where the cable end came off) I suspect the g-box detent, ball bearing fix, cms shift arrestor and the like are reaches for your symptoms, but maybe. They are a bandaid for poorly shimmed gear stacks from the factory. That being said, if you can get the cover off with the transmission in place, the g-box detent (or a ball bearing) are cheap to do and do no harm. That cover was bonded immovable on the one car I tried to do this on with the transmission in place on the car because of the limited room to work. It is easier with the transmission out because you can use a longer tool for leverage. Motor and transmission mounts should be good regardless, if they�re worn, replace them. Others have had good luck addressing shifting issues this way. I can�t wrap my head around why, but that�s just me. Motor mounts are easy, transmission mounts usually require removal and a press, but can be done in place with a special tool from AGA (I have one, but a fellow rennlister rents it out if you don�t - maybe @dporto ). Anything more than that, leave it to the pros. Tearing the gearbox apart is major surgery, and you want to think twice before you tackle it. I�m not sure I�d do it again myself (jury is still out on whether it worked). I think synchros would have symptoms in shifting issues, not popping out of gear.

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This seems to be the best step by step process...start with the easy (and cheap) stuff first.

I did not notice any issues with third or 6th. I agree, would rather go with the easy and cheap stuff before tearing apart the transmission.

Please reply back with your results. I think we all have our theories as to what will solve your problem based on each person's personal experience.

I had similar problem with this, but mine wasn't severe. It was just the shift linkage popping out underneath the car.

Hello everyone, thought I would share an update. 1. Checked all the cables, they were attached properly, and shifter was aligned with the tool. Issue persisted. 2. Gbox detent installed. Shifts like a beauty again. Sweet! No expensive fix required. Thank you all for the suggestions, and direction.

Thanks for feedback. Awesome that you got a solution and can get back to driving it again , without that worry.

Yes, thanks for the update and final conclusion. I hate when a thread gets left unconcluded. And glad your fix was simple and painless !!!

Glad it worked out. That G-box detent is an amazing piece of kit. I'm so glad I didn't have to look at tearing into the transmission. Congrats on a simple solution.