996.2 GT3 twitchy on the highway, please help.
#31
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Still need clarification on what is happening when the car gets squirrelly. Is it during hard acceleration at high speed? Is it hard braking at high speed? Straight or turning? Is it simply cruising at 180 kph that the car feels unsettled?
#32
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When you are using the engine as a brake, yes, but how often do you use a $25K transaxle as a brake on public roads?
Still need clarification on what is happening when the car gets squirrelly. Is it during hard acceleration at high speed? Is it hard braking at high speed? Straight or turning? Is it simply cruising at 180 kph that the car feels unsettled?
Still need clarification on what is happening when the car gets squirrelly. Is it during hard acceleration at high speed? Is it hard braking at high speed? Straight or turning? Is it simply cruising at 180 kph that the car feels unsettled?
Furthermore, the clunk I was referring to was the OP's, not yours
Oh and a broken spider gear will cause the rear end to jump sideways, similar to what the OP stated.
#33
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Also the LSD can affect braking in a straight line. That said, Johan any new news? My suggestion at this point:
- Check the front shocks - remove them, pull the springs, look for leaks, see how they compress.
- Check tie rods, steering rack, and ball joints.
- Make sure your tires are good
- Do a nut & bolt in the front
- Check the rear LSD: Jack the rear, car in neutral, have someone prevent one side from turning, Get a torque wrench on the other side, and see where that side breaks away - more details somewhere
#34
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Also the LSD can affect braking in a straight line. That said, Johan any new news? My suggestion at this point:
- Check the front shocks - remove them, pull the springs, look for leaks, see how they compress.
- Check tie rods, steering rack, and ball joints.
- Make sure your tires are good
- Do a nut & bolt in the front
- Check the rear LSD: Jack the rear, car in neutral, have someone prevent one side from turning, Get a torque wrench on the other side, and see where that side breaks away - more details somewhere
You could also check the shocks in the car (ADAC in Germany is able test this)
The rear tires must be the "same". If they are different (age) the car is not driving straight beyond 120 km/h. I had this with some Pirelli tires
@Ray: Any more details on the LSD check method ?
Thomas
#36
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Thanks for all the advice guys. I am currently under lock down in my home. As soon as we are allowed to go out again I will take the GT3 to my technician for some diagnostics. At least I now have a list of possible causes to investigate.
- toe links rear
- all bushings
- shocks
- sway bar (pre tension)
- LSD ; I will flush the gearboxoil to be safe
- toe links rear
- all bushings
- shocks
- sway bar (pre tension)
- LSD ; I will flush the gearboxoil to be safe
#37
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I am locked down in Honduras...
Anyway: I would also suggest:
Anyway: I would also suggest:
- Check tie rods, steering rack, and ball joints.
- Make sure your tires are good
- Do a nut & bolt in the front
- Check the rear LSD: Jack the rear, car in neutral, have someone prevent one side from turning, Get a torque wrench on the other side, and see where that side breaks away - more details somewhere
#40
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Also the LSD can affect braking in a straight line. That said, Johan any new news? My suggestion at this point:
- Check the front shocks - remove them, pull the springs, look for leaks, see how they compress.
- Check tie rods, steering rack, and ball joints.
- Make sure your tires are good
- Do a nut & bolt in the front
- Check the rear LSD: Jack the rear, car in neutral, have someone prevent one side from turning, Get a torque wrench on the other side, and see where that side breaks away - more details somewhere
. Some posters have stated a worn LSD's symptoms are twitchy handling braking or accelerating in a turn. Those were my symptoms. The worn LSD would have to slip-lock-slip-lock in a fraction of a second to degrading handling in that manner.
i.e. a worn or damaged LSD doesn't necessarily become the same as an open differential and have no effect on handling, the bad LSD could actually degrade handling
Further evidence of unusual or unexpected bad LSD symptoms...one poster here states that his LSD is long worn out and does not affect handling...Maybe his is worn such that it does act as an open diff
Last edited by black04; 03-19-2020 at 07:41 PM.
#41
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Can anyone give any input on when the shocks typically fail or need to be replaced?
IE do most fail around 25K miles or 16 years
or 50K miles or 16 years
75K miles?
thanks
IE do most fail around 25K miles or 16 years
or 50K miles or 16 years
75K miles?
thanks
#42
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This is not to be a thorough test of the assembly, but rather will provide some small amount of information. I am aware that to properly evaluate the LSD, it would be removed.
It occurs to me that a static LSD test might be meaningless in general.
As far as this car's specific LSD, there could be damage or damage and wear causing the LSD to lock-slip-lock-slip in less than a second, causing straight-line twitchiness.
i.e. a worn or damaged LSD doesn't necessarily become the same as an open differential and have no effect on handling. The damaged LSD could hurt handling in a turn or straight-line
Furthermore, regarding the poster that states that his LSD is long worn out...Maybe his is worn such that it does act as an open diff...whereas mine and other's worn LSD degraded handling with the slip-lock-slip syndrome
As far as this car's specific LSD, there could be damage or damage and wear causing the LSD to lock-slip-lock-slip in less than a second, causing straight-line twitchiness.
i.e. a worn or damaged LSD doesn't necessarily become the same as an open differential and have no effect on handling. The damaged LSD could hurt handling in a turn or straight-line
Furthermore, regarding the poster that states that his LSD is long worn out...Maybe his is worn such that it does act as an open diff...whereas mine and other's worn LSD degraded handling with the slip-lock-slip syndrome
#43
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DUDE...I literarally did the same thing as you did.
Just got my 997 4S yesterday and spinned out today on highway, hitting a puddle in heavy rain.
Luckily I didn't hit anything other than scuffing my right front wheel. Hopefully the car is fine.
I ordered the Ohlins R/T coilovers for my car since the rear right absorber has gone bad. (car is 2008, 104k miles) I heard that OEM Bilstein absorbers tend to leak at around this mileage/age.
I wonder if something is losened in the steering system of your car?
Just got my 997 4S yesterday and spinned out today on highway, hitting a puddle in heavy rain.
Luckily I didn't hit anything other than scuffing my right front wheel. Hopefully the car is fine.
I ordered the Ohlins R/T coilovers for my car since the rear right absorber has gone bad. (car is 2008, 104k miles) I heard that OEM Bilstein absorbers tend to leak at around this mileage/age.
I wonder if something is losened in the steering system of your car?
#44
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#45
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Elephant Racing makes a set of thrust bearings: https://www.elephantracing.com/911/c...t-bearing-kit/
However, the open roller bearing can't last long once dirt gets in there.
This link is not the one I remember, but looks similar. Instead of a roller bearing it uses what looks like Delrin (a slippery version of nylon) sandwiched between stainless steel washers. Dirt is less likely to degrade these, in my opinion.
https://www.splparts.com/products/sw...t-washers.html
However, the open roller bearing can't last long once dirt gets in there.
This link is not the one I remember, but looks similar. Instead of a roller bearing it uses what looks like Delrin (a slippery version of nylon) sandwiched between stainless steel washers. Dirt is less likely to degrade these, in my opinion.
https://www.splparts.com/products/sw...t-washers.html
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JJT (03-20-2020)