Redline MTL eller MT 90

[Torbjorn968]

Sökt igenom forumet om info om Växellådsolja. Redline verkar favoriten, frågan är bara om det är MTL eller MT 90 som skall användas? MTL verkar vara en 70 W 80 olja och 90 en tjockare olja. Om jag förstått saken rätt är 75 W 90 specificerat av Porsche så MT-90?

Från redlines site:

http://www.redlineoil.com/content/files ... 20Info.pdf" onclick="window.open(this.href);return false;

RED LINE MTL® and MT-90 are designed to provide
excellent protection and improved shiftability for manual
transmissions and transaxles. MTL and MT-90 have
cured the problem of hard shifting in numerous
transmissions which have notoriously difficult shifting.
The secret to their success is two-fold. First, they have
the appropriate coefficient of friction for most manual
transmission synchronizers. Many gear oils, engine oils,
and ATFs are too slippery for proper synchro
engagement. Secondly, the viscosity characteristics of
MTL and MT-90 allow proper shifting over the entire temperature
range which the transmission will experience.
The synthetic base oils used have a very high viscosity
index which provides relatively constant viscosity as
temperature changes. MTL is a low 75W, almost a 70W,
at very low temperatures and a high 80W, nearly an
85W, at elevated temperatures, providing adequate
viscosity to prevent wear and deaden gear noise. MT-90
is a thicker 75W90 version of MTL. The shear stability
and oxidation stability of these products are excellent,
thus the physical characteristics of Red Line MTL and
MT-90 will change little with use.
Red Line MTL is classified as a 75W/80W gear lubricant
satisfying the API Service requirements of GL-3 and
GL-4. MTL also satisfies motor oil viscosities SAE
5W/10W/30, and the viscosity requirements for ATFs.
MT-90 is a 75W90 GL-4 and also satisfies motor oil
viscosities SAE 10W/15W/40. The additive chemistry
used is non-corrosive, so even though they will provide
GL-4 performance, they will not corrode synchros or
bushings. Because of its low corrosivity, Red Line MTL
and MT-90 could also be used in transmissions requiring
GL-1 or GL-3 lubricants. Seal compatibility is designed to
be similar to petroleum-based lubricants.
BENEFIT SUMMARY
• Eliminates notchy shifting
• Designed for manual transmissions and transaxles
• Perfect synchronizer coefficient of friction
• Enables high-speed downshifting
• Excellent shifting even when cold • Eliminates gear whine and rattle at high temperatures
• High-performance gear protection
• Non-corrosive toward synchronizers
• Satisfies manual transmissions and transaxles requiring
motor oils, or GL-1, GL-3, or GL-4 gear oils
IMPROVES SHIFTING
Red Line MTL and MT-90 are able to improve shifting in
most manual transmissions and transaxles. They
provide a relatively constant viscosity as temperature
changes and provides the proper coefficient of friction to
allow synchronizer engagement. Most gear oils are very
viscous at lower temperatures. This higher viscosity
requires increased shift effort to move the synchronizer
gears with the shift fork and to squeeze the oil from
between the synchronizer cone and the mating surface
attached to the gear. Without contact of these two
surfaces, the gear speeds will not be synchronized and
locking of the synchromesh gears will not occur.
Excessive viscosity results in a longer time required to
synchronize before locking occurs.
Viscosity of common lubricants at 0°C (32°F) is
compared with Red Line MTL in the chart below. Note
that the viscosity of ATF and 10W30 motor oil seems to
be adequate. These lubricants are not well suited for
transmission use because of two factors - shear stability
and improper coefficient of friction - which will be
discussed in more detail later. At even lower
temperatures such as -17.7°C (0°F), the differences
between conventional lubricants and Red Line MTL are
even more dramatic. At such a temperature many of
these lubricants would prevent shifting into certain gears,
depending on the design of the transmission.
All oils are slippery, and with most lubricated
components, the slipperier the better, but this is not so
with manual transmissions. The synchronization of
shifting gears requires friction to transfer energy from the
synchronizer, which is locked to the input shaft, to its
mating surface attached to the gear to be locked in as
the drive gear. Few modern transmissions use sliding
gears to change gearing other than for reverse gearing.
Synchromesh transmissions have the gear pairs constantly
in mesh. The drive gear is selected by using the
shift forks to slide a synchronizer ring, which rotates at
the same speed as the input shaft, in contact with the
selected drive gear. Once the drive gear is brought to
the same speed as the input shaft, the locking ring on
the synchro assembly is allowed to slide over and lock
into the drive gear.
The time this process takes depends on how easily the
synchro ring moves and the rate of frictional energy
transfer between the two synchronizer surfaces. Higher
viscosity lubricants slow the sliding of the synchro ring on
the input shaft and require a longer time for the oil to be
squeezed out from between the mating synchronizer
surfaces. After the lubricant is squeezed out, the
coefficient of friction of the lubricant determines the rate
of frictional energy transfer between the two surfaces.
Slippery lubricants such as hypoid gear oils can take too
long to synchronize the gears, which promotes
synchronizer wear. Red Line MTL and MT-90 has a
coefficient of friction which is greater than conventional
oils, allowing a quicker transfer of frictional energy. The
graph below shows the desirable friction curve
demonstrated by Red Line MTL compared to
conventional lubricants. Note how the coefficient of
friction is greater for the MTL than all others except the
motor oil. Some motor oils have an adequate dynamic
coefficient of friction, but most have problems with the
static and low velocity coefficient of friction which can
result in clashing.
Clashing of the gears (actually clashing of the
synchromesh gears, since the drive gears are always in
contact) can occur if excessive shift effort is used in
order to shift the locking ring into place before the
surfaces have achieved equal speed. It may also occur
at the end of a reasonably smooth shift if an instability
exists in the coefficient of friction, causing stick-slip to
occur. In this form of clashing, the ring slides on the
mating synchro gear, but a sudden slippage causes a
grinding of the gears. In order to prevent stick-slip from
occuring and the gear clashing which results, the
coefficient of friction should inflect downward as the
relative speed drops to zero.
1500 1250 1000 750 500 250 0
0.06
0.08
0.10
0.12
0.14
0.16
0.18
80W GL-1
Red Line MTL
80W GL-5
Dexron II
SAE 30 SF Motor Oil
RPM
MTL
Coefficient of Friction, μ
Red Line MTL
80W Gear Oil
ATF
10W30 Motor Oil
0
1000
2000
3000
4000
Viscosity, cP @ 0°C (32°F)
0
10,000
20,000
30,000
40,000
Viscosity, cP @ -18°C (0°F)
80W90 Gear Oil
80W90 Gear Oil
80W Gear Oil
ATF
10W30 Motor Oil
Viscosity
@32°F
Viscosity
@0°F
Red Line MTL

[Henka_E]

Det står inget här om oljan funkar om man har LSD/Torsen diff - hur vet man det?


Och - citat från Redline: "MTL & MT-90 are not for use in differentials with hypoid gears"

Centrumväxeln är ju hypoid, så det borde väl då vara

http://www.redlineoil.com/product.aspx?pid=47&pcid=7

Alltså, 75W90 NS GL-5 Gear Oil, som vi ska köra med? Eller?

[Torbjorn968]

Jag har Quaife diff, skall då inte spela någon roll enligt tidigare ägare. Frågar nu Quaife.

//TL

[Corleone]

Har rett ut detta en gång med Red Lines specialist.

MT 90 is the shit!

[Henka_E]

Hur gick det med det här?

[Torbjorn968]

Quaife sa att vanlig transmissionsolja var det som gällde med deras diffar. Körde MT 90.

//T