Gear grind when trying to go into reverse / 2nd in cold
#1
Gear grind when trying to go into reverse / 2nd in cold
2009 997.2 6MT
Recently changed trans fluid to Mobilube from sun coast and used exactly three bottles. RL and all 997 groups mentioned needing exactly three, but when finishing the job, I had only a few drops come out of the drain hole, and very slowly, at that.
The car now grinds when trying to go into reverse or second gear when stationary and even moving unless I let the car warm up for 1-2 minutes.
Once warm, shifting is great. I did experience some normal 1-2 notchy shifting before the fluid change, but not this. This is a full on grind as if I don’t even have the clutch engaged.
Do you think there wasn’t enough fluid added? Can I choose any normal 75w90 trans fluid to add until a significant amount of oil drains out, or should I order more mobilube from sun coast?
Recently changed trans fluid to Mobilube from sun coast and used exactly three bottles. RL and all 997 groups mentioned needing exactly three, but when finishing the job, I had only a few drops come out of the drain hole, and very slowly, at that.
The car now grinds when trying to go into reverse or second gear when stationary and even moving unless I let the car warm up for 1-2 minutes.
Once warm, shifting is great. I did experience some normal 1-2 notchy shifting before the fluid change, but not this. This is a full on grind as if I don’t even have the clutch engaged.
Do you think there wasn’t enough fluid added? Can I choose any normal 75w90 trans fluid to add until a significant amount of oil drains out, or should I order more mobilube from sun coast?
#2
Rennlist Member
Did you save the old fluid to be able to check for metal particles? And maybe even to do a used oil analysis?
I would (over) buy more PTX to do another drain and refill. Or, at least. to add more to see if it changes the bad behavior.
Had you experienced any possible clutch related bad behavior prior to this? Is it possible the clutch hydraulic circuit needs to be bled?
I would (over) buy more PTX to do another drain and refill. Or, at least. to add more to see if it changes the bad behavior.
Had you experienced any possible clutch related bad behavior prior to this? Is it possible the clutch hydraulic circuit needs to be bled?
#3
RL Community Team
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Did you use the correct fill level hole? There are two holes with plugs up there and you need to use the lower of the two. If you didn't lose any oil when filling, you should have 1"-2" of oil left in the last bottle of the three.
#4
Yes, we used the correct hole. We used the funnel method and some oil was stuck in the hose (gravity limitation) at the end of the procedure, but the bottles were empty.
I believe one of my choices is to find a 75w90 gear oil locally at an auto parts store and take it somewhere to be topped off, but I’m not sure if the 5-10 grinds that occurred have generated metal shavings that require draining.
The other is to buy 4L PTX, wait a week plus for ground shipping, then take it somewhere for a full drain and fill.
Thoughts? Thanks guys.
also to the poster above I didn’t save any oil but it was shifting without grinding and looked physically fine.
#5
RL Community Team
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I've never heard of this from using PTX. Almost sounds like a hydraulics issue. If you put the shifter into 1st before selecting reverse, does it still do it. That's good practice on any manual transmission car as it stops things from spinning because first gear has a synchro and reverse doesn't.
There is no way to get rid of the 1st and 2nd gear catch in a 997 when cold - they all do it because a different synchro material is used for those 2 gears than the other 4.
There is no way to get rid of the 1st and 2nd gear catch in a 997 when cold - they all do it because a different synchro material is used for those 2 gears than the other 4.
#6
RL Community Team
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2009 C2S 193K miles
I never heard of this... that it got worse after a fill with PTX. I highly doubt not having a complete fill would do that. I have filled mine with exactly three liters of the stuff a few times with not issues, only improvement. Now I buy 4 liters and that extra bottle, I use up over time. I change it every 30K miles or so. I would not top off with any oil, even a good one. I am just paranoid about the additive packages working well together.
BTW, using the top fill hole won't cause problems... a tech did it to mine one time.
I don't have an answer... very odd. Let it work through before you spend any more money.
Peace
Bruce in Philly (now Atlanta)
I never heard of this... that it got worse after a fill with PTX. I highly doubt not having a complete fill would do that. I have filled mine with exactly three liters of the stuff a few times with not issues, only improvement. Now I buy 4 liters and that extra bottle, I use up over time. I change it every 30K miles or so. I would not top off with any oil, even a good one. I am just paranoid about the additive packages working well together.
BTW, using the top fill hole won't cause problems... a tech did it to mine one time.
I don't have an answer... very odd. Let it work through before you spend any more money.
Peace
Bruce in Philly (now Atlanta)
#7
2009 C2S 193K miles
I never heard of this... that it got worse after a fill with PTX. I highly doubt not having a complete fill would do that. I have filled mine with exactly three liters of the stuff a few times with not issues, only improvement. Now I buy 4 liters and that extra bottle, I use up over time. I change it every 30K miles or so. I would not top off with any oil, even a good one. I am just paranoid about the additive packages working well together.
BTW, using the top fill hole won't cause problems... a tech did it to mine one time.
I don't have an answer... very odd. Let it work through before you spend any more money.
Peace
Bruce in Philly (now Atlanta)
I never heard of this... that it got worse after a fill with PTX. I highly doubt not having a complete fill would do that. I have filled mine with exactly three liters of the stuff a few times with not issues, only improvement. Now I buy 4 liters and that extra bottle, I use up over time. I change it every 30K miles or so. I would not top off with any oil, even a good one. I am just paranoid about the additive packages working well together.
BTW, using the top fill hole won't cause problems... a tech did it to mine one time.
I don't have an answer... very odd. Let it work through before you spend any more money.
Peace
Bruce in Philly (now Atlanta)
It’s so odd that it was fine before and now I get a horrible grind after. It’s really only when cold, once it warms up, it’s perfectly fine.
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#8
Rennlist Member
You think it’s safe to drive? You wouldn’t buy more PTX and either add until it streams out the fill hole or complete another drain and fill with at least 3.3 liters?
It’s so odd that it was fine before and now I get a horrible grind after. It’s really only when cold, once it warms up, it’s perfectly fine.
It’s so odd that it was fine before and now I get a horrible grind after. It’s really only when cold, once it warms up, it’s perfectly fine.
If grinding persists, I wouldn't be driving it until repaired.
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PatrickBateman (11-26-2023)
#9
The dilemma is I understand warming up the car can cause bore score, even though I have a 997.2 DFI car.
I didn’t get the grind when the temp outside was warm (70) but did when it was 34 out.
#10
Rennlist Member
The grind doesn’t occur if I warm up the car for 90-120 seconds before driving off, though I do at times need to double clutch into second and depress the clutch a few times to get into first (also at times) until the oil is at 175 degrees..
The dilemma is I understand warming up the car can cause bore score, even though I have a 997.2 DFI car.
I didn’t get the grind when the temp outside was warm (70) but did when it was 34 out.
The dilemma is I understand warming up the car can cause bore score, even though I have a 997.2 DFI car.
I didn’t get the grind when the temp outside was warm (70) but did when it was 34 out.
My transmission was replaced when the car had 25K miles but overall Manual transmissions haven't had many issues.
Ferrari's are notorious for grinding until they are warmed up. I dealt with this issue on my 308 for years. And 1978-1983 Porsche 911sc's had huge issues with transmission syncros and they needed replacing early on.
For now, since the issue is new and only happening in cold weather, my take would be to drive car in 1st gear around neighborhood until cars warmed up and or double clutch into 2nd. But whatever you do don't let it grind.
See how things progress. Maybe do another transmission fluid change this winter and see how that works out.
I have read that in some rare cases the syncros can be an issue in the 997 tranny. I have no idea why my transmission was replced but shows on the Carfax at 25K miles. My car now has 107K.
Is your reverse gear grinding also going away after car is warmed up? If thats the case back into garage after returning and car is warmed up.
Last edited by groovzilla; 11-26-2023 at 04:12 PM.
#11
In previous Threads, the grinding going from 1st to 2nd has been discussed while car is warming up. Seems to be somewhat common.
My transmission was replaced when the car had 25K miles but overall Manual transmissions haven't had many issues.
Ferrari's are notorious for grinding until they are warmed up. I dealt with this issue on my 308 for years. And 1978-1983 Porsche 911sc's had huge issues with transmission syncros and they needed replacing early on.
For now, since the issue is new and only happening in cold weather, my take would be to drive car in 1st gear around neighborhood until cars warmed up and or double clutch into 2nd. But whatever you do don't let it grind.
See how things progress. Maybe do another transmission fluid change this winter and see how that works out.
I have read that in some rare cases the syncros can be an issue in the 997 tranny. I have no idea why my transmission was replced but shows on the Carfax at 25K miles. My car now has 107K.
Is your reverse gear grinding also going away after car is warmed up? If thats the case back into garage after returning and car is warmed up.
My transmission was replaced when the car had 25K miles but overall Manual transmissions haven't had many issues.
Ferrari's are notorious for grinding until they are warmed up. I dealt with this issue on my 308 for years. And 1978-1983 Porsche 911sc's had huge issues with transmission syncros and they needed replacing early on.
For now, since the issue is new and only happening in cold weather, my take would be to drive car in 1st gear around neighborhood until cars warmed up and or double clutch into 2nd. But whatever you do don't let it grind.
See how things progress. Maybe do another transmission fluid change this winter and see how that works out.
I have read that in some rare cases the syncros can be an issue in the 997 tranny. I have no idea why my transmission was replced but shows on the Carfax at 25K miles. My car now has 107K.
Is your reverse gear grinding also going away after car is warmed up? If thats the case back into garage after returning and car is warmed up.
Answer to last question is yes, no grinding whatsoever once car is fully warmed up. Drives completely normal.
I am thinking to add some more PTX fluid until I get a steady amount of drops to indicate the gearbox is full. If that doesn’t fix it, I’ll order enough to do another drain and fill as you mentioned.
If that doesn’t work; I might need to move back to SoCal, ha!
Worst case scenario, can you replace synchros without rebuilding trans? Or is this a full rebuild scenario?
#12
Rennlist Member
Answer to last question is yes, no grinding whatsoever once car is fully warmed up. Drives completely normal.
I am thinking to add some more PTX fluid until I get a steady amount of drops to indicate the gearbox is full. If that doesn’t fix it, I’ll order enough to do another drain and fill as you mentioned.
If that doesn’t work; I might need to move back to SoCal, ha!
Worst case scenario, can you replace synchros without rebuilding trans? Or is this a full rebuild scenario?
I am thinking to add some more PTX fluid until I get a steady amount of drops to indicate the gearbox is full. If that doesn’t fix it, I’ll order enough to do another drain and fill as you mentioned.
If that doesn’t work; I might need to move back to SoCal, ha!
Worst case scenario, can you replace synchros without rebuilding trans? Or is this a full rebuild scenario?
But I'm not a "wrench" and someone with more knowledge will chime in.
I have no idea of just syncros can be replaced in the 997 transmission. The early 911sc 915 transmission usually needed 1st & 2nd gear syncros replaced and repair was just replacing those syncros.
I owned lots of 911sc's and dealt with the issue many times.
Good luck going forward and your idea of adding some fluid is good idea. Hopefully it is something simple.
Last edited by groovzilla; 11-26-2023 at 05:39 PM.
#13
RL Community Team
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First, relax.
Order another litter and just add it to the point it drbbles out. Then report back.
It is ok to drive the car.
Peace
Bruce in Philly (now Atlanta)
Order another litter and just add it to the point it drbbles out. Then report back.
It is ok to drive the car.
Peace
Bruce in Philly (now Atlanta)
#14
"The dilemma is I understand warming up the car can cause bore score, even though I have a 997.2 DFI car."
Warming the engine up causes bore score ?
Warming the engine up causes bore score ?
#15
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