shifting issues
 

Sometimes the shifting in my 1987 911 Turbo is smooth going from first to second and third to fourth and sometimes it is not. The same applies to going from second to first. The consensus on this site is to check the shift linkage going to the transmission. I have looked at the shift coupler and there is some play in it. I can turn it left and right and up and down a little. How much play in that assembly is acceptable? I am guessing none and that I need a new couple assembly. It also appears that I have a transmission fluid leak around the shaft that enters the transmission from the shift linkage. In order to fix the leak do I have to remove the transmission? All help is appreciated.

Hmm. I thought the G50 Coupler was pretty solid compared to the OEM 915. Are you sure it is not the bushing/s at the shifter?

I would check there first.

My buddies 87 also leaked there not sure how he fixed it, sorry can't help.

I would also check the transmission mounts and engine mounts. I had inconsistent shifting from worn-out mounts on both, once replace the issue was resolved. (Not sure if this would apply to a G50 transmission).

'87 turbo still ran a 930 4spd gearbox, very similar in many ways to the 915. The turbo was the last car to get a G50 variant. Didn't happen until the 964 chassis.

I had shifting issues and after replacing the side plate on the transaxle that holds the cable, and just about every other cable part finally got it right. It is the most finicky adjustment and then all of a sudden its perfect. Had thoughts of bad synchros and every kind of advice and a fianl cable adjustment made it right. Whew. Before doing anything costly work on the cable and all it's associated parts and try adjusting first. Hopefully you get lucky like I did.

The coupler is supposed to have a small amount of "play," but diagnosis is usually done by visual inspection of the bushings (2). If the bushings are all there (no crumbs inside the rubber boot or lying on the bottom of the tunnel), and do not show cracking or deterioration you should be OK.

Your shift rod seal leak is a tricky one that requires a huge amount of patience. You do not have to remove the trans from the car, but you should have access from underneath (either using a lift, or a jack with jack stands, etc.). CAUTION: ALWAYS BE SURE THAT THE CAR IS STABLE AND CANNOT FALL WHEN WORKING UNDER IT. AFTER THE JACK STANDS ARE IN POSITION ALWAYS LEAVE THE FLOOR JACK UNDER THE CAR FOR AN EXTRA LAYER OF PROTECTION!!!

After you expose the leaking seal you will have to make a tool to remove it. You do not want to scar/scratch the surrounding aluminum as you remove the seal, so a normal screwdriver will not work. I ground a shallow hook into the tip of a long, very thin shaft screwdriver, and kept modifying it until I could grab the seal and, by prying against a small piece of wood, loosen the seal (it will be very tight).

Shifting difficulty. Have you considered changing your oil type/make? I have found over many years of working with these cars that Kendall 80w/90 "DINO" NS-MP gear oil will deliver the best shifting characteristics. You do not want to use synthetic oil in your gear box, so call around your area and see if you can find the Kendall gear oil. FYI; Kendall also makes synthetic gear oil, do not use that. Replacing gear oil is the easiest "fix" there is, and the cheapest!

Finally, what's the history regarding your clutch?

The clutch seems to be in good shape.

I will check the rest of the suggestions this coming weekend and I will looking for that oil too.

Thanks everyone for the input!