996 gear selection

[mtm81]

In normal driving , everyday motoring , my gear selection is fine if a little notchy when cold (normal)

However when the car Is hot and I've come to a standstill (traffic, parking etc) if I go from neutral to get another gear (usually first second or reverse) if wont go in.. Feels smooth not stiff but feels like there is a flex right at the point of engaging the gear and it won't go..

Sometimes I can 'slam' it in, and others if I turn off the car it will then go in ok..

Pumping the pedal does nothing..

I've narrowed it down in my mind to three possibilities:

1) air in system - it had a new clutch a few thousand miles ago when I bought the car so think there maybe a poor bleed in there , or one of the cylinders is going?

2) gear linkage ?

3) gearbox mount - I occasionally do get a clunk so I think even if this isn't the issue - my mount may still need to be swapped..

Should say the car is 996 3.6 02 model with 72k on the clock

Any thoughts would be most welcome!

[Loren]

When was the last time you did a brake/clutch fluid flush and re-fill?

You should be able to check the linkage under the car - look for bent parts.

While you are there check the transmission mounts - a badly broken mount can cause shifting problems too.

[JasonStern]

Do you have a short shift kit installed? It should be easy to tell as the stock 996 shifter has diesel big rig lengthed throws. If so, it might also be worth lifting the center console and verifying that the shift cables are properly calibrated. You might need to contact the kit manufacturer to acquire the alignment tool to correct. But, even without the alignment tool, you should be able to at least see whether one of the cables is binding/causing excessive tension. Short shift kits also make it much more difficult to shift when inclement weather causes the transmission oil to become very cold, but that would be more of a winter problem.

[mtm81]

Hi,

No I don't have a short shift installed - all standard.

[JFP in PA]

When was the last time the gear oil was changed, and what brand/type of oil is in the gear box?

[bzguy]

What gear box oil is recommended ?

[JFP in PA]

What gear box oil is recommended ?

Porsche uses a unique full synthetic gear oil that is made for them to their specs, which no other manufacturer use. Several aftermareket oil companies have admitted that they do not have a match for it. Several of our customers have experimented with several aftermarket brands, but always went back to the OEM stuff due to excessive noise, and poor shifting problems. As soon as the OEM stuff was back in the car, the problems went away.

I'm sure someone will chime in here and tell us they have used brand X or Y and not had problems, but that has not been our experience, and we change a lot of gear oil.

[bzguy]

Thank you for your reply JFP in PA.

I suppose the only place where you can get this OEM stuff is @ Porsche dealer ?!

[Loren]

Thank you for your reply JFP in PA.

I suppose the only place where you can get this OEM stuff is @ Porsche dealer ?!

In Belgium you can get many Porsche OEM parts from Carnewal.com

[Silver_TT]

Just to elaborate on what JFP is saying, those customers that used aftermarket gear oils and went back to the OEM to eliminate problems were very lucky. Using non-OEM gear oils that are otherwise viewed favorably outside the Porsche world (Redline, Royal Purple, etc) in these gearboxes can do permanent damage to the gears, synchros and other metal-on-metal components of these gearboxes. If you talk to Stan at Gbox he will tell you do not to use anything but the OEM gear oil or you're asking for trouble. For the price of the damage this can do, it's shocking to me that more Porsche owners aren't aware of it.

[Rapewta]

I changed the gear oil 15K miles ago with Mobil 1, Synthetic gear lubricant LS. 75W-90.

Not sure if it is on any list of approved gear oils but the tranny is quiet and shifts are smooth.

I don't track the 99 C2 6sp coupe.

[Gary S K Lee]

im recently having rough gear changes problem...when is the ideal mileage to have the transmission oil changed?? my clock is at 80,000 km's.

[JFP in PA]

im recently having rough gear changes problem...when is the ideal mileage to have the transmission oil changed?? my clock is at 80,000 km's.

You did not mention your year and model, but Porsche suggest 90,000 miles (`145,000Km) for manual gear box oil changes; that said, more realistically I would be doing it sooner at around 40,000 miles. As you are at 80,000 Km, or about 49,000 miles, you are in the window for a change. Strongly suggest refilling the gearbox with the OEM lube, as it is a rather unique full synthetic product which works very well.

[hi8ha]

"Porsche uses a unique full synthetic gear oil that is made for them to their specs, which no other manufacturer use."

How about Mobil Delvac 75w-90? Isn't the transmission oil the same as the gear oil?

[Gary S K Lee]

im recently having rough gear changes problem...when is the ideal mileage to have the transmission oil changed?? my clock is at 80,000 km's.

You did not mention your year and model, but Porsche suggest 90,000 miles (`145,000Km) for manual gear box oil changes; that said, more realistically I would be doing it sooner at around 40,000 miles. As you are at 80,000 Km, or about 49,000 miles, you are in the window for a change. Strongly suggest refilling the gearbox with the OEM lube, as it is a rather unique full synthetic product which works very well.

mine's a 02 C4S with tiptronic tran...guess it's about time to change oil.

[bzguy]

Thank you for your reply JFP in PA.

I suppose the only place where you can get this OEM stuff is @ Porsche dealer ?!

In Belgium you can get many Porsche OEM parts from Carnewal.com

Thank you Loren ; Carnewal didn't have it at that time, but managed to get oil from teile.com (in Poland), the exact Porsche OEM stuff, but cheaper than from Porsche :)

Edited March 9, 2014 by bzguy

[JFP in PA]

"Porsche uses a unique full synthetic gear oil that is made for them to their specs, which no other manufacturer use."

How about Mobil Delvac 75w-90? Isn't the transmission oil the same as the gear oil?

Depends upon the model and year, some do but others do not. And in this case, it's a Tiptronic.

[hi8ha]

"...if I go from neutral to get another gear (usually first second or reverse)"... "... had a new clutch a few thousand miles ago...". These comments made me think it was a manual.

[JFP in PA]

"...if I go from neutral to get another gear (usually first second or reverse)"... "... had a new clutch a few thousand miles ago...". These comments made me think it was a manual.

You are mixing posters and time frames, today's poster said:

"mine's a 02 C4S with tiptronic tran...guess it's about time to change oil."

[hi8ha]

Oops, sorry.

Thanks