There is a squealing noise (like a bicycle brake) when turning the car in low speeds; I believe that it comes from the ZF transaxle (diff). The ZF shifts like butter and I’m using Castrol TAF-X 75W-90 oil. Anyone with a clue?
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I had a bit of a whine.Kind of scrubbing, Turned out to be a rear pad rivet touching the rotor. Definatly take off your wheels and check your brakes. If your ZF is squeiling....it must be serious...check your u joints for wear...
Yes. Check that the wheels are torqued tight.
If they are loose, that means the rotors are loose also and will wobble, like the wheels in a turn and squeak or squeel.
If they are loose, that means the rotors are loose also and will wobble, like the wheels in a turn and squeak or squeel.
quote:Originally posted by PanteraDoug:
Yes. Check that the wheels are torqued tight.
If they are loose, that means the rotors are loose also and will wobble, like the wheels in a turn and squeak or squeel.
No, it is not from the wheels or brakes!
The reason I don't belive it is in the ZF is because it is full of oil.I would suspect a ZF problem to be "clunking". If you have a squeel, I suspect somthing dry. I would do a wheel off inspection, Also try turning the tires with them off the ground and see if you can make it happen. Try to rock the wheel up and down to check for bearing play. It is trying to tell you something. Does it do it both right and left?
quote:Originally posted by Fredrik Gustavsson:quote:Originally posted by PanteraDoug:
Yes. Check that the wheels are torqued tight.
If they are loose, that means the rotors are loose also and will wobble, like the wheels in a turn and squeak or squeel.
No, it is not from the wheels or brakes!
Well Fredfrik if you can't find it a bunch of us will have to jump a plane and come and visit.
Do you have a sauna, plenty of beer, and plenty of attractive single female companionship for us?
We won't stay long. A couple of months should do it.
quote:Well Fredfrik if you can't find it a bunch of us will have to jump a plane and come and visit.
Do you have a sauna, plenty of beer, and plenty of attractive single female companionship for us?
We won't stay long. A couple of months should do it
They don't have to be single,but beer a must.Should be no trouble finding the problem.
quote:There is a squealing noise
Is your neighbor's cat perhaps missing?
Have you tried lifting rear wheels off the ground, locking one wheel and trying to turn the other,this will get the differential working and simulate what happens with tight turns at low speeds. It could be that the plates in the diff are very worn and that there is no locking taking place hence the squelling as the clutch plates are worn in the diff itself. The diff does very little work when under normal road conditions as corners are not tight enough to work it. the gears and CWP are not affected hence no problem with the rest of the box.
I think I know what it is now. This is a common problem on rear axles with LSD (limited slip diff) when using the wrong type of oil. It can be solved by using an oil with LS additive to get the friction at the diff right, but for the Pantera that has a transaxle it can be problem with shifting when using LS oil.
I found this conversation on the internet that explains it:
Dave
Thanks for your answer. I don't understand why you recommend the 75W90NS instead of the regular 75W90 gear oil.Your net site has the following statement:
"75W90NS - recommended for manual transmissions and non-limited-slip transaxles that recommend 90 WT oils. Can be used in racing limited-slip units to increase lockup and reduce wheel spin. Street-driven rear-wheel drive cars should use regular Red Line 75W90 or 80W140"
Can you help me understand why you have advised the opposite to this?
I recommend the 75W90NS in the Pantera because the gear lube is being used to lubricate both the transmission and the differential. The NS fluid doesn't have friction modifiers so isn't too slippery for the synchros and will allow good shiftability. The note that you sent and underlined is specifically relating to rear differentials, not transaxles. If the transaxle uses a clutch type limited slip and excess chatter occurs when making a slow tight turn, then a slight amount of friction modifier could be added to the NS to reduce this, being aware that too much can effect the shiftability. The 75W90 contains 5% friction modifier and this could be too much for some synchros.
Regards, Dave
Red Line Oil
I found this conversation on the internet that explains it:
Dave
Thanks for your answer. I don't understand why you recommend the 75W90NS instead of the regular 75W90 gear oil.Your net site has the following statement:
"75W90NS - recommended for manual transmissions and non-limited-slip transaxles that recommend 90 WT oils. Can be used in racing limited-slip units to increase lockup and reduce wheel spin. Street-driven rear-wheel drive cars should use regular Red Line 75W90 or 80W140"
Can you help me understand why you have advised the opposite to this?
I recommend the 75W90NS in the Pantera because the gear lube is being used to lubricate both the transmission and the differential. The NS fluid doesn't have friction modifiers so isn't too slippery for the synchros and will allow good shiftability. The note that you sent and underlined is specifically relating to rear differentials, not transaxles. If the transaxle uses a clutch type limited slip and excess chatter occurs when making a slow tight turn, then a slight amount of friction modifier could be added to the NS to reduce this, being aware that too much can effect the shiftability. The 75W90 contains 5% friction modifier and this could be too much for some synchros.
Regards, Dave
Red Line Oil
quote:Originally posted by Fredrik Gustavsson:
I think I know what it is now. This is a common problem on rear axles with LSD (limited slip diff) when using the wrong type of oil. It can be solved by using an oil with LS additive to get the friction at the diff right, but for the Pantera that has a transaxle it can be problem with shifting when using LS oil.
I found this conversation on the internet that explains it:
Dave
Thanks for your answer. I don't understand why you recommend the 75W90NS instead of the regular 75W90 gear oil.Your net site has the following statement:
"75W90NS - recommended for manual transmissions and non-limited-slip transaxles that recommend 90 WT oils. Can be used in racing limited-slip units to increase lockup and reduce wheel spin. Street-driven rear-wheel drive cars should use regular Red Line 75W90 or 80W140"
Can you help me understand why you have advised the opposite to this?
I recommend the 75W90NS in the Pantera because the gear lube is being used to lubricate both the transmission and the differential. The NS fluid doesn't have friction modifiers so isn't too slippery for the synchros and will allow good shiftability. The note that you sent and underlined is specifically relating to rear differentials, not transaxles. If the transaxle uses a clutch type limited slip and excess chatter occurs when making a slow tight turn, then a slight amount of friction modifier could be added to the NS to reduce this, being aware that too much can effect the shiftability. The 75W90 contains 5% friction modifier and this could be too much for some synchros.
Regards, Dave
Red Line Oil
Fredrik, we already have our 'plane tickets. Was it the two months?
quote:Originally posted by PaulF:
Have you tried lifting rear wheels off the ground, locking one wheel and trying to turn the other,this will get the differential working and simulate what happens with tight turns at low speeds. It could be that the plates in the diff are very worn and that there is no locking taking place hence the squelling as the clutch plates are worn in the diff itself. The diff does very little work when under normal road conditions as corners are not tight enough to work it. the gears and CWP are not affected hence no problem with the rest of the box.
Today I lifted one side of the car and tried to rotate the rear wheel that was in the air. With gearbox in neutral I can turn the wheel easily, when in first gear I can hardly turn it at all and in fifth gear it’s easier. When both rear wheels are in the air and the gearbox in neutral I can turn each wheel independently of each other very easy and in first gear when turning one wheel the other turn in opposite direction.
That sounds good. so you know that the diff is locking fine, and the clutch plates arn't slipping.
quote:Originally posted by PaulF:
That sounds good. so you know that the diff is locking fine, and the clutch plates arn't slipping.
Paul I have rewritten the previous post because I made a mistake when testing yesterday. I can say that the parking brake was involved!
Fredrik, With the gearbox in neutral, the handbrake off, raise both the back wheels off the ground. Turn one wheel, what happens to the other?? it should turn in the same direction as the one you are trying to turn. Next, stop one wheel from turning, by wedging a block of wood or something under the tyre. Now try to turn the other one again. Does it turn easily? It should not turn easily, it should however turn if you grip it tightly and apply a good force, because you are overcoming the locking of the plates in the diff. If it does turn easily you have no locking in the diff, and the other wheel will turn in the opposite direction, because of the action of the sun and planet gears,when you remove the block. mail me at following address if you need more help.[URL=paul@flemingpaul.wanadoo.co.uk