Originally Posted By: ghortat
Originally Posted By: zeng
Most modern GL5 today meets ASTM D130-12 Copper Strip Test 1a or 1b , among other things with the inclusion of metal deactivators in its additive system.
http://www.ptplab.net/upfile/201402/19/154823776.pdf
It's an indication of copper/brass friendliness , and I would consider any present day GL5 with ASTM D130-12 Copper Strip Test 1a or 1b ratings, as safe for present day yellow metals.
I would bypass a GL4 and consider the use of a GL5 with D130 1a/1b rating.
Note: ASTM D130-12 Copper Strip Test ratings 1a or 1b being part of requirements of MT1 / J2360.
The said ENEOS meets the following :
PERFORMANCE LEVEL
API Service GL 5 / MT-1, SAE J2360 (MIL-PRF-2105E )
ZF TE-ML 02,05, 07, MAN 341SL, 342SL, 3343 SL
Scania STO 1:0 (box), Mack GO-G, MB 235.0
http://www.eneos-oil.eu/products/gearoils/58-75w90eneospremiumgear-valtomu-olaj
http://drivelinenews.com/axle-insights/api-category-gl-4-not-the-right-choice-for-modern-equipment/
So , you are well and good.
I would normally agree but the thing is that my car is manufactured in 2008 and the aforementioned MTL GL-4 like MT-90 or Ford X5-MT have been fully tested and they work without causing any problem to the transmission whatsoever. So we cannot claim that GL-4 oils are NOT the right choice.
I am not sure of anybody here claiming a GL4 oil is NOT the right choice for applications that call for GL4.
Having said this, it doesn't mean an appropriate oil like Eneos in question is not suitable and thus cannot be used in applications that calls for GL4.
Originally Posted By: ghortat
The proper question would be whether SOME GL-5, when they meet specific conditions, could be used for SPECIFIC, synchonized transmissions which originally call for GL-4 oil.
Assuming Eneos' performance level claim are real, it's GL5 performance level claim is insignificant in our context. It supposedly has, not only SAE J2360 approval but OEM approvals of several reputable manufacturers. Without going further into specific details, I would venture to guess these approvals are inclusive of synchronised transmissions.
Originally Posted By: ghortat
ANyhow, besides the J2360 passed indication which this oil carries, there is a logical leap here. Its excellent resistance for wear, corrosion, foaming and Oxidation compared to a GL-4 may be true but that does not mean that it wont cause MORE harm to the synchros than for example MT-90. The yellow metal safe indication does NOT mean that it wont cause more harm to the synchros. The one does not necessarily contradicts the other.I dont know how can we ever be sure unless we used such a product or tested it for similar case/application.
Basing on your logic, neither does it mean that a GL4 would cause LESS harm to a synchro than a J2360.The argument is moot.
Btw, automotive gear oils can be tested for J2360 approval or any of above mentioned OEM approvals.Though the same cannot be said for GL4 , IIRC.
Originally Posted By: ghortat
Comparing their viscocity based on 75w90 GL-4 chemical compound since they seemed alike, make me believe that corrosion effects had to be similar.
Corrosion effects caused by this Eneos vis-a-vis a GL4 is a non-issue, unlike a GL5 of 15 to 20 years ago.
Inadequate operating viscosity would not cause corrosion effects on copper/brass synchros , however it generates unwarranted irreversible component wear in transmission bearings and gears, and occasionally synchros.
