Pinion Gear Failure
#18
But this is not down to stripping of the gear…. It’s down to lining of the case breaking up and getting in between… causing the wear.
In the case of the revisions CW&P solutions… the concern there IS down to more load being put though a smaller than stock contact patch as the new set has more teeth but smaller area + the added power and significant torque … so there worry is that they might strip.
In the case of the revisions CW&P solutions… the concern there IS down to more load being put though a smaller than stock contact patch as the new set has more teeth but smaller area + the added power and significant torque … so there worry is that they might strip.
#19
That spalling doesn't look pretty - it looks worse than Warwick's pinion gear teeth. And you say you didn't find any metal filings in the oil. If you didn't, I'll bet that the case hardening has been ground up to dust and distributed through the whole transmission & bearings ....
How many km on the gearbox and what lubricant have you been using?
How many km on the gearbox and what lubricant have you been using?
Seems this gearbox really is the weak point in the car, no wonder Porsche are telling all their dealers to destroy them once replaced
Last edited by O5C4R; 07-18-2021 at 08:58 PM.
#21
Yes, that thing would be destroyed in short order.
__________________
2016 GT4-R
Rick DeMan
DeMan Motorsport
Upper Nyack, NY
845 727 3070
Porsche Sales & Service
Porsche Race services and parts
www.DeManMotorsport.com
2016 GT4-R
Rick DeMan
DeMan Motorsport
Upper Nyack, NY
845 727 3070
Porsche Sales & Service
Porsche Race services and parts
www.DeManMotorsport.com
#22
I realized I never answered this: it's a high pitched whine that increases with road speed (not RPM), and modulates with throttle application (kind of sounds like morse code when you apply partial throttle). We drained the trans oil earlier this year and didn't see anything metallic, so in the absence of anything explicitly pointing towards material failure we filled it back up and it's been running fine since.
Just for further information, the car has made this same noise since before I owned it; I drove it for a weekend when it had around 32,000 miles and it made the exact same sound. And when we had it apart to drop in the new 2-5 ratios + LSD, nothing looking wrong with the R&P. Still, given that I'm now putting more power through the trans with the 4.5L (and since we're seeing pinion failures with stock engines), I'm very likely going to get this replaced sometime in the near future purely as a preventative measure (plus not having that annoying sound will be a major plus).
Just for further information, the car has made this same noise since before I owned it; I drove it for a weekend when it had around 32,000 miles and it made the exact same sound. And when we had it apart to drop in the new 2-5 ratios + LSD, nothing looking wrong with the R&P. Still, given that I'm now putting more power through the trans with the 4.5L (and since we're seeing pinion failures with stock engines), I'm very likely going to get this replaced sometime in the near future purely as a preventative measure (plus not having that annoying sound will be a major plus).
#23
So unfortunately I am doing research for my 981 failed pinion gear , started with a noise (whine) between 2000 -3000 rpm with slight load on engine. My GT4 only has 32k mikes but has allot of track days.
So what options do I have ? Has anyone changed their gear ratios while it was apart? Cost for new gearbox ? Thanks
So what options do I have ? Has anyone changed their gear ratios while it was apart? Cost for new gearbox ? Thanks
#24
Rick,
My 981 Cayman has joined the ranks of failed pinion gear, my shop 9Automation reached out to you for suggestions. I am also considering changing gear ratio while its out. You have excellent reviews on your 4.5 L and your exclusive gear set must compensate for torque.
Appreciate your feedback ,
Thanks,
Bill Thompson
My 981 Cayman has joined the ranks of failed pinion gear, my shop 9Automation reached out to you for suggestions. I am also considering changing gear ratio while its out. You have excellent reviews on your 4.5 L and your exclusive gear set must compensate for torque.
Appreciate your feedback ,
Thanks,
Bill Thompson
#25
Rick,
My 981 Cayman has joined the ranks of failed pinion gear, my shop 9Automation reached out to you for suggestions. I am also considering changing gear ratio while its out. You have excellent reviews on your 4.5 L and your exclusive gear set must compensate for torque.
Appreciate your feedback ,
Thanks,
Bill Thompson
My 981 Cayman has joined the ranks of failed pinion gear, my shop 9Automation reached out to you for suggestions. I am also considering changing gear ratio while its out. You have excellent reviews on your 4.5 L and your exclusive gear set must compensate for torque.
Appreciate your feedback ,
Thanks,
Bill Thompson
Unfortunately the ring and pinion is not available anywhere and once it goes there is not much alternative. A used R&P might show up sometime but rarely.
We stock used GT4 transmissions that have been inspected and ready for short gearing. We could offer you a small trade in credit for yours towards a re-geared ready to go GT4 trans.
Please Call the shop
845 727 3070
#26
Condolences for your loss. If this is the right "part", $9,456.46?
https://www.getporschesilverspringpa...g2LWdhcw%3D%3D
https://www.getporschesilverspringpa...g2LWdhcw%3D%3D
#27
I didn’t see this thread the first time, but now that it’s bumped I will offer my two cents. A decade ago when we were running 987.2 cars in Grand Am and World Challenge this was always the mode of failure. Most teams kept a complete spare gearbox in the trailer just in case.
In many instances it’s just wear and tear and the first thing to wear out. However there are a couple things one must be careful about to avoid prematurely suffering this fate.
1. oil change intervals. If you track your car you can’t do it according to the book. Even if you aren’t racing, you are heating the oil up more, causing it to break down more quickly. For years I’ve told people to change their gear oil after every 2-3 weekends of DEs. That’s maybe 10-15 hours of track time. In race cars we change them after every event.
2. gearbox cooling. Porsche saw the light and started adding a cooler as standard with 981. For a dedicated track car, I still don’t consider that adequate. Get an aftermarket supplemental cooler like BGB makes.
on that same topic, is the LSD. 987 gearboxes rarely had one from the factory. All these cars you guys have run them stock. That generates more heat. Add my lsd or other high friction aftermarket lsd, and that’s even more heat. Given that the ring and pinion is the most poorly lubricated section of the gearbox it would be hard to over cool it.
the good news is that even though it’s 6 years later there’s still good availability of takeout 3rd gear recall gearboxes floating around for cheap. At one point there were several dealers dumping them for $1000 each. Tear it down, and replace the wonky 3rd gear and you’re good to go.
In closing I have one final comment. An incompetent mechanic who doesn’t properly install a replacement LSD can also cause this. Ring and pinion settings are done to tolerances of 0.01mm. If a shop just throws some new bearings on an LSD and drops it in there without setting preload and backlash this is the result. If they tell you they can install an LSD for a few hours labor they likely aren’t doing it right. Low bidders are low bidders for a reason.
In many instances it’s just wear and tear and the first thing to wear out. However there are a couple things one must be careful about to avoid prematurely suffering this fate.
1. oil change intervals. If you track your car you can’t do it according to the book. Even if you aren’t racing, you are heating the oil up more, causing it to break down more quickly. For years I’ve told people to change their gear oil after every 2-3 weekends of DEs. That’s maybe 10-15 hours of track time. In race cars we change them after every event.
2. gearbox cooling. Porsche saw the light and started adding a cooler as standard with 981. For a dedicated track car, I still don’t consider that adequate. Get an aftermarket supplemental cooler like BGB makes.
on that same topic, is the LSD. 987 gearboxes rarely had one from the factory. All these cars you guys have run them stock. That generates more heat. Add my lsd or other high friction aftermarket lsd, and that’s even more heat. Given that the ring and pinion is the most poorly lubricated section of the gearbox it would be hard to over cool it.
the good news is that even though it’s 6 years later there’s still good availability of takeout 3rd gear recall gearboxes floating around for cheap. At one point there were several dealers dumping them for $1000 each. Tear it down, and replace the wonky 3rd gear and you’re good to go.
In closing I have one final comment. An incompetent mechanic who doesn’t properly install a replacement LSD can also cause this. Ring and pinion settings are done to tolerances of 0.01mm. If a shop just throws some new bearings on an LSD and drops it in there without setting preload and backlash this is the result. If they tell you they can install an LSD for a few hours labor they likely aren’t doing it right. Low bidders are low bidders for a reason.
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#28
GTgears,
Thanks for the good info I will inquire with John at BGB on the supplemental cooler.
It's not a cheap repair , are than any other factors to this failure? driving style ? torque on the pinion ?
How are these 4.5L replacement engines not causing failures ?
Thanks for the good info I will inquire with John at BGB on the supplemental cooler.
It's not a cheap repair , are than any other factors to this failure? driving style ? torque on the pinion ?
How are these 4.5L replacement engines not causing failures ?
#29
The original source of these gearboxes was the Euro market Audi A4 TDi. They were designed for a high torque application and the first 987 boxes even had the auto Union Audi 4 rings.
With 987.2 they made a new case casting for the DFi engine bolt pattern and from then on out they all had the Porsche trademark triangle P on them. At the same time they actually beefed up the size of the ring.
Power never has been or will be the limiting factor on these gearboxes. Guys in South Africa use them in 917 replicas with twin turbo audi sixes making nearly double the “big” GT4 engines US vendors build.
With 987.2 they made a new case casting for the DFi engine bolt pattern and from then on out they all had the Porsche trademark triangle P on them. At the same time they actually beefed up the size of the ring.
Power never has been or will be the limiting factor on these gearboxes. Guys in South Africa use them in 917 replicas with twin turbo audi sixes making nearly double the “big” GT4 engines US vendors build.