Diff problem

[izanagi]

Hi all.
I've a TRD LSD on my Trueno but i think it locks also when i'm turning.
Is it possible that this lsd has been welded ?
Thanks

[jondee86]

If it was welded you would not have any doubt
Normal LSD requires a bit of load on to lock, so doing a
turn with only a light touch on the gas it should work
like an open diff. But do a turn with your foot hard on
the gas it will lock... either skid the inside wheel or if
you have the power, skid both wheels

Cheers... jondee86

[izanagi]

So, my diff is not welded but it's the first time that i drive with a 2 way diff and it's very strange and hard.

Envoyé depuis mon GT-I9100 avec Tapatalk

[jondee86]

(08-23-2014 01:20 AM)izanagi Wrote:  So, my diff is not welded but it's the first time that i drive with a 2 way diff and it's very strange and hard.

Here is what Kaaz has to say about the 1. 1.5 and 2-way LSD's...

As you can see, the 2-way LSD is designed for race cars, and will be a lot
more aggressive in lock-up than the standard Toyota OEM LSD. You will need
to modify your driving habits around town

Cheers... jondee86

[allencr]

Is the TRD LSD's design like a Kaaz with its pinion's having ramps to put different pressure on the clutches: full-half-none, or is it like an OEM/factory &most other LSDs that relies on spring pressure so that that is operating absolutely equal in drive & coast?
Jack up 1 wheel, trans in N, and try turning that wheel. Howzit turn? Seems to be completely locked solid with a little bit of axle spline play to the other wheel on the ground or spins freely or something in between?

[izanagi]

Another problem.
A mecanic specialist in Toyota AE86 has just changed my diff bearings. Pinion and carrier.
I just installed the diff on the car and it's still whining at acceleration and only in 3, 4, 5 gears.
Where could come this whinning noise ?
Rear wheel bearings ?

Envoyé depuis mon GT-I9100 avec Tapatalk

[jondee86]

(08-24-2014 08:05 PM)izanagi Wrote:  Where could come this whinning noise ?
Rear wheel bearings ?

Generally speaking, wheel bearings do not whine... they rumble. A whine
is typically the noise a differential makes when the crown wheel and pinion
are not perfectly matched. If the diff has had new bearings, it is possible
that it is now set up slightly differently (backlash corrected for wear etc)
and the contact patch is not quite in the same place as before.

Depending on how loud the noise is, and if it is there all the time, or only
at certain speeds/rpm's, you could just keep driving it and hope that after
a while the noise gets less. There really is not much else that can be
done. If there was some mechanical problem with the diff, I'm sure your
mechanic would have discovered it while he was replacing the bearings.

Cheers... jondee86

[Ivan141]

If it only makes noise in specific gears that would point to the gearbox as a suspect would it not?

[izanagi]

(08-25-2014 08:58 AM)jondee86 Wrote:  

(08-24-2014 08:05 PM)izanagi Wrote:  Where could come this whinning noise ?
Rear wheel bearings ?

Generally speaking, wheel bearings do not whine... they rumble. A whine
is typically the noise a differential makes when the crown wheel and pinion
are not perfectly matched. If the diff has had new bearings, it is possible
that it is now set up slightly differently (backlash corrected for wear etc)
and the contact patch is not quite in the same place as before.

Depending on how loud the noise is, and if it is there all the time, or only
at certain speeds/rpm's, you could just keep driving it and hope that after
a while the noise gets less. There really is not much else that can be
done. If there was some mechanical problem with the diff, I'm sure your
mechanic would have discovered it while he was replacing the bearings.

Cheers... jondee86

I think that my pinion preload is not enough.
Is it possible that it makes some noise ?

Envoyé depuis mon GT-I9100 avec Tapatalk

[jondee86]

Anything that changes the point of contact between crown wheel and pinion
could potentially lead to a whine from the diff. But if the mechanic replaced
the pinion bearings, I should think that he set the pre-load correctly.

Last time I researched this question (as it comes up regularly) I believe that
I read that the noise is a resonant frequency generated by the teeth of the
pinion striking (contacting) the teeth of the crown wheel. Typically the
noise will be speed related, rising to a maximum at a certain speed, and then
fading away as the speed increases.

In effect, the crown wheel is ringing like a bell under the impact of the
pinion teeth. Settin the pinion depth incorrectly is said to be one possible
cause (contact patch not in the centre of the tooth face).

Cheers... jondee86