Hi guys. Complicated one here, need some help! What would be the best fit SAE grade and oil type (mineral/ synthetic) for the front and rear diffs and transfer for my 4wd v6 2006 4Runner? Here are the conditions:
1. Not looking for fuel economy here, but rather for the longest possible life expectancy of the diffs and transfer.
2.Locality. Climate: up to 100 F or even more in summer - for a month or so, and down to - 10 F in winter, sometimes even colder - but for no longer than 2-3 weeks in total, mostly within 5 to 14 F.
The car is driven in a city located in mountains, daily altitude difference en routes are from 0.5 to 1.5 miles above the sea level = severe conditions as per the manual and higher loads on the diffs and in general.
3. Original manual quotes: for v6 models with multi-mode transmision(my case) front and transfer - 75w90, rear - 90/ 80w / 80w90 depending on the temperature. For instance, v8 models with full time should have 80w90 all over. GL-5.
4. Well-known Toyota revision of 2008 pushes to switch to 75w85 all over. Fuel economy up, who cares about the diffs anymore?
5. Preference as to the SAE grade: gonna stick to the book. Good quality 80w90 may not be available though. If so, what about 75w90 all over? Or what about Castrol 75w140 in the rear and 75w90 for the rest? It potentially protects better due to being thicker, but wouldn't it be too thick and lead to excessive wear? For comparison: typical mineral 80w90's viscocity: 15 cct at 100 C and 150 cct at 40 C, pour point around -25 C. Synthetic Castrol 75w140 - 25 cct at 100 C and 175 cct at 40 C, pour point - 54 C.
6. Available reputable brands: no Amsoil/ Redline stuff here. OEM Toyota 75w90 / 80w90 / 75w85, all are virtually not available as I would have to order from a dealer and then wait for about two months - I don't possess that type patience and that type of loyalty to the dealer. So, the choices really are: Motul (imported from France), Liquimoly (imported from Germany), Mobil1 (made for local region, so not sure if the production standards and formulas are the same with the US/ European products) and Castrol (also local).
7. My model is with open differential. Would it hurt using LSD compatible oils? I know you should do vice versa.
I really would appreciate your help. Thanks!
1. Not looking for fuel economy here, but rather for the longest possible life expectancy of the diffs and transfer.
2.Locality. Climate: up to 100 F or even more in summer - for a month or so, and down to - 10 F in winter, sometimes even colder - but for no longer than 2-3 weeks in total, mostly within 5 to 14 F.
The car is driven in a city located in mountains, daily altitude difference en routes are from 0.5 to 1.5 miles above the sea level = severe conditions as per the manual and higher loads on the diffs and in general.
3. Original manual quotes: for v6 models with multi-mode transmision(my case) front and transfer - 75w90, rear - 90/ 80w / 80w90 depending on the temperature. For instance, v8 models with full time should have 80w90 all over. GL-5.
4. Well-known Toyota revision of 2008 pushes to switch to 75w85 all over. Fuel economy up, who cares about the diffs anymore?
5. Preference as to the SAE grade: gonna stick to the book. Good quality 80w90 may not be available though. If so, what about 75w90 all over? Or what about Castrol 75w140 in the rear and 75w90 for the rest? It potentially protects better due to being thicker, but wouldn't it be too thick and lead to excessive wear? For comparison: typical mineral 80w90's viscocity: 15 cct at 100 C and 150 cct at 40 C, pour point around -25 C. Synthetic Castrol 75w140 - 25 cct at 100 C and 175 cct at 40 C, pour point - 54 C.
6. Available reputable brands: no Amsoil/ Redline stuff here. OEM Toyota 75w90 / 80w90 / 75w85, all are virtually not available as I would have to order from a dealer and then wait for about two months - I don't possess that type patience and that type of loyalty to the dealer. So, the choices really are: Motul (imported from France), Liquimoly (imported from Germany), Mobil1 (made for local region, so not sure if the production standards and formulas are the same with the US/ European products) and Castrol (also local).
7. My model is with open differential. Would it hurt using LSD compatible oils? I know you should do vice versa.
I really would appreciate your help. Thanks!
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