Difficult shifting G50 transmission.

[Gotmike+911]

I have an ‘88 911. It’s difficult to shift into 2nd gear and feels like it’s slightly “nicking” a gear when shifting into 3rd gear.
I just had the clutch replaced, so it’s not a clutch issue. I experienced the same shifting issues before and after the new clutch.
Does anyone out there know what’s going on?

[Gdixon]

Change trans fluid. I changed mine recently after 48 years! It wasn’t bad before but greatly improved now.

[toddinmd]

sounds like the 3rd gear syncro is going. Diffinetly change the gear lube, that will make a difference in shifting. Also when you drain (or whoever does) make sure to strain the fluid as it comes out to make sure there's not broken bits.

When shifting to 3rd you could try to double clutch to see if that helps.

[Tom]

sounds like the 3rd gear syncro is going. Diffinetly change the gear lube, that will make a difference in shifting. Also when you drain (or whoever does) make sure to strain the fluid as it comes out to make sure there's not broken bits.

When shifting to 3rd you could try to double clutch to see if that helps.

Agreed.

That said, in my '85 (915 transmission) a long time ago, I had one crunchy gear. The car was under a warranty contract that came with the car when I bought it, so my mechanic at the time (Bob Grigsby, one of the greats) opened it up and discovered the shifter fork inside was bent. The warranty covered it, so he put in a new shifter fork, and the transmission shifted like new again. The G50 may be less prone to that (I don't know), but it's another possibility. If new fluid and clutch don't help, you probably need to look inside unfortunately. Kevin Gross, aka @Catellus Engineering, is our resident transmission rebuilder.

[Gotmike+911]

There's a lot of ambiguity about best type of oil for the '88 911. Service manual reads the correct oil to be SAE grade 20W50. Furthermore, synthetic oil is not recommended by the manufacturer. I'm currently using Valvoline VR1 SAE 20W50.
Anybody have an oil you like better...and why? Thx!

[Catellus Engineering]

Usually when you have difficulty shifting into second or third gears, and the others are fine, it's simply a matter of worn synchros. You definitely want to correct the issue before you experience a lot more "nicking" because that's a sign you are wearing the gears' engagement teeth, which starts to get expensive.

[Catellus Engineering]

Thanks. I had the shifter fork replaced with the clutch and had the gear lube changed a couple years ago (there was nothing in the old gear oil). Any suggestions for the a mechanic in the San Diego area?

Great if you're able to find someone local. But don't be put off by distance: it's easy and not horribly expensive to ship your transmission to a gearbox specialist who will do the job right.

[Tom]

Thanks. I had the shifter fork replaced with the clutch and had the gear lube changed a couple years ago (there was nothing in the old gear oil). Any suggestions for the a mechanic in the San Diego area?

Great if you're able to find someone local. But don't be put off by distance: it's easy and not horribly expensive to ship your transmission to a gearbox specialist who will do the job right.

To Kevin's point, I shipped my 951 transmission to him and was super happy with his work. He kept me updated, only replaced the parts that needed replacing, gave me the option on replacing so-so parts, gave me all the old parts back, and just generally did the kind of job you only get from someone who knows these particular transmissions inside and out. There may be someone great near you too (Southern California in general must have its share) but to me it's the kind of job worth finding the right person, even if not local.