991.2 how to shift a cold manual transmission
01-20-2019, 06:03 PM
#46
Rennlist Member
It has been ill advised for decades now to warm your car (any car from any manufacturer) from cold start idle the way you are doing it, as it takes a longer time to get up to temperature with no loads on the engine. The longer the car is grinding away at cold temperatures at idle, the more wear is occurring and, I suspect, the more your oil is getting diluted from water vapor. Not to mention the environmental impact from wasted fuel.
This thread also has me scratching my head at the number of folks that expect their transmissions to be smoothly shifting to 1st during a rolling stop- this puts immense stress on the synchros to spin up to match that engine/transmission speed, and frankly is pretty hard on them. On the rare occasion that I feel it's important to downshift to 1st when I'm not standing still (like when I'll need to instantly get moving again), I do my best to revmatch which is a little awkward on a car that is crawling near a stop. Best to shift into first from a dead stop.
This thread also has me scratching my head at the number of folks that expect their transmissions to be smoothly shifting to 1st during a rolling stop- this puts immense stress on the synchros to spin up to match that engine/transmission speed, and frankly is pretty hard on them. On the rare occasion that I feel it's important to downshift to 1st when I'm not standing still (like when I'll need to instantly get moving again), I do my best to revmatch which is a little awkward on a car that is crawling near a stop. Best to shift into first from a dead stop.
01-20-2019, 07:45 PM
#47
^^ Agree. It’s even listed in many different owners manuals to drive off right away. I drive gingerly and progressively during warmup. Too much RPM will starve the engine of oil. Too little RPM when cold and idling might also starve the engine of oil. You want a healthy oil pressure and a healthy amount of heat, and driving off immediately accomplishes this.
Around my city it regularly goes down to -15, even -25 some nights.
At at these low temps what is the advisable start up procedure ? Genuine ask? Do you at least wait until the start up rpm settles down, or do you still gentle drive off?
As a precaution I plug in a batter tender to the car, but may opt to a battery warmer instead....depending how much longer the cold lasts.
ps. I took my car to the dealer to have them look at the transmission fluid level and cable alignment. Both were found to normal however after my visit the cold whether performance of the cold manual transmission was more than acceptable. Still a little stiff but managable enough to go around. Ike magic my problem went away.
01-20-2019, 10:10 PM
#48
Rennlist Member
I've driven manual transmission cars since I was 15. Some in very cold temps (like -15C). When a manual transmission is cold, your best bet is to up-shift slowly, and double-clutch or heel-toe downshift. End of story. The name of the game is matching engine speed to input shaft speed. This puts the minimum stress on the synchros (if it has them) and gearsets. All cold manual transmissions feel notchy until they warm up. Frankly the 991.2 transmission feels identical in this respect to my former 23 year old 993 and it's G50.
cheers!
cheers!
01-21-2019, 09:41 AM
#49
Rennlist Member
Around my city it regularly goes down to -15, even -25 some nights.
At at these low temps what is the advisable start up procedure ? Genuine ask? Do you at least wait until the start up rpm settles down, or do you still gentle drive off?
As a precaution I plug in a batter tender to the car, but may opt to a battery warmer instead....depending how much longer the cold lasts.
ps. I took my car to the dealer to have them look at the transmission fluid level and cable alignment. Both were found to normal however after my visit the cold whether performance of the cold manual transmission was more than acceptable. Still a little stiff but managable enough to go around. Ike magic my problem went away.
11-20-2021, 03:07 PM
#51
I have the exact same problem as the op with a 991.2 c2s. If the cars not heated up it won't shift into 2nd. I took it to Porsche as it's still got an extended warranty on it with 51km. They say it needs a new transmission. Now just waiting to see if Porsche covers it or if they'll find an excuse not to pay.
11-22-2021, 12:57 PM
#52
Rennlist Member
Originally Posted by machdown;[url=tel:17797462
17797462]I have the exact same problem as the op with a 991.2 c2s. If the cars not heated up it won't shift into 2nd. I took it to Porsche as it's still got an extended warranty on it with 51km. They say it needs a new transmission. Now just waiting to see if Porsche covers it or if they'll find an excuse not to pay.
11-23-2021, 03:54 PM
#53
Does this make sense to anyone. Any advice on what I can say to Porsche to get them to cover it. I feel like range 3 is normal
11-23-2021, 04:19 PM
#54
Rennlist Member
Who knows how far back the cold-weather shifting issues go. My 993 would have that issue from 1st to 2nd. I would apply very light pressure on the shifter to shift gears. You force things, you f**k things up. Luckily I live in a residential area and have a chance to warm the transmission up before heading onto main roads.
My 991.1 shifts well at the above ambient temperature and like butter at higher ambient temperatures. But then I bought the car used with 157 kms or 98 miles on it, so it was basically new and not abused by someone else.
The manual transmission in my BMW E36 coupe had a factory fill of ATF in it. Listed in the manual.
11-23-2021, 11:50 PM
#55
RL Community Team
Rennlist Member
Rennlist Member
You would thinks so right? Porsche says they're not covering it because of over revs in range 3. 38 of them to be exact. None in range 4 5 or 6.
Does this make sense to anyone. Any advice on what I can say to Porsche to get them to cover it. I feel like range 3 is normal
Does this make sense to anyone. Any advice on what I can say to Porsche to get them to cover it. I feel like range 3 is normal
11-24-2021, 07:51 AM
#56
Rennlist Member
Pretty normal stuff as far as stick cars go. Just treat them slow and gentle till warm. When it is very cold out I don’t see an issue with a 2-3 minute warmup. Which is not really excessive and usually by the time I get myself sorted in the car ends up about right.
I haven’t noticed too much of this with my 991.2 but the garage is heated and I haven’t left the car to go ice cold outside much.
Redline fluids have helped in other cars. Not sure I would do that in a modern 911.
I haven’t noticed too much of this with my 991.2 but the garage is heated and I haven’t left the car to go ice cold outside much.
Redline fluids have helped in other cars. Not sure I would do that in a modern 911.
11-24-2021, 06:47 PM
#57
I have to say this is kind of funny. I have a 2019 GTS with a manual trans and 2nd gear can be a problem and I had this same experience with many of the manual trans cars I have had beginning with a 1966 MGB. I have never found a sure fire solution to the problem as shifting up or down into 2nd can be difficult when cold and when hot.
11-24-2021, 07:51 PM
#58
Pretty normal stuff as far as stick cars go. Just treat them slow and gentle till warm. When it is very cold out I don’t see an issue with a 2-3 minute warmup. Which is not really excessive and usually by the time I get myself sorted in the car ends up about right.
I haven’t noticed too much of this with my 991.2 but the garage is heated and I haven’t left the car to go ice cold outside much.
Redline fluids have helped in other cars. Not sure I would do that in a modern 911.
I haven’t noticed too much of this with my 991.2 but the garage is heated and I haven’t left the car to go ice cold outside much.
Redline fluids have helped in other cars. Not sure I would do that in a modern 911.
Here's the report. Seems like it was mostly done by previous owner. I got the car 3 years ago with 26k. I put on about 25k
11-24-2021, 08:00 PM
#59
Three Wheelin'
All manual transmissions do this to some extent when cold ...all my motorcycles are no different ....you let the car roll a bit back or nudge it slightly forward when stopped and when at low rpm you blip the throttle a bit between gears and "feel" your way in ... 
You know .
You know .