it is no 4wd button in a rav4 .... its a center diff lock button wich applies 50/50 power distrubution to the front rear.... should not be pressed unless stuck somewhere.....
aslong as the vehicle is under guaranty by toyota, use toyota fluids... guaranty people sometimes requests a sample of the oil and wont warranty the work if found to be other oils.... same with parts if they are related too the fault (only applies if the aftermarked part is in relation with the fault)
In the USA, the 4WD unit is in the rear diff. It holds the engaging clutch packs that engage electronically. The transfer case is just that, the gearing to bring a PTO shaft to the rear. You will notice the transfer case oil is almost always cleaner to spotlessly clean because nothing is really happening in there but static power transfer. At least that is how i understood it. I may be wrong at least on nothing happening much in the transfer case, but most of the 4WD drive stuff is happening in the rear diff with solenoids.
They can sample my ATF oil all they want. I can dump my WS ATF oil out 100 miles after picking it up new from the dealer and as long as I add WS comparable ATF. See sampling of specs below that Redline D6 is comparable to. Here in the USA I am protected by the Magnuson-Moss Warranty Act. Or gear oil as you stated above . I run Redline there too, but when I get my boat I might switch to Amsoil Severe Gear because I can get it right down the road. I will use ATF as my example since I have used this example many times and I can use aftermarket oil cooler as an example too.
Below are all the ATF fluids that my favorite ATF oil Redline D6 is comparable to. The law states ( paraphrasing) that if Toyota says the warranty of the tranny is only good if I run their oil, they have to supply it for FREE when I want to change it during the warranty period. And it is up to them to prove that the fluid (in my case) Redline D6 caused the warranty failure. It happens so little that they would never take it to court, because any good attorney would find a good petroleum fluid engineer and all they would have to say is they were running Redline D6 when the failure happened and that fluid engineer would want to check the D6 that came out of the car and make sure it had it's additive package in it and if it did he would always side with the Redline in this case or say...Amsoil Signature Series ATF. Both far superior ATFs. Redline D6 is group 4/5 Ester based full synthetic ATF then the semi-synthetic group 2/3 crap Toyota WS is. Read about base stocks at my link. A far superior base stock and add a far superior additive package with the Redline or Amsoil vs Toyota WS and other OEM ATFs, with the exception of Hyundai/Kia SP4-M that is a group 4/5 Ester based OEM oil that is an excellent high end ATF.
Understanding the Differences in Base Oil Groups
I am still in the beginnings of my research, but it looks as if an external ATF aftermarket cooler if install with "best practices" would be safe to install on a warranted new car/truck under the Magnuson-Moss Act. I have checked with 4 Toyota dealers so far and 2 said they would honor the trans failure without question if the cooler had proper sized lines that were the shortest possible, long hose radius turns as not to restrict flow and the right diameter hose. ( a pro install or factory quality install even if the owner did it) The 2 others would defer to Toyota, because they did not know how to handle it.
Remember it is up to Toyota to prove basically in the court of law why it failed, they can't defer it for ME or the owner to prove Toyota is wrong in denying the warranty claim. All burden is on them. So it happens so rarely they just fix it, it just is not worth fighting. Plus any good attorney can get experts to prove the failure is in the failure averages. High end "bouquet" AFT is far superior then OEM ATF, and a properly installed after market cooler keeps the temp down. Both pushing failure rates down by a high margin.
At least here in the USA there is a weird dogma about warranty and using ONLY the manufactures products on forums like this one. The minute you bring up the Magnuson-Moss Warranty Act you would not believe how the conversation changes at the dealership with people that know the law. A complete 180 deg change. The others who "don't know, what they don't know" keep following the company warranty dogma line to scare you to buy their product. I bet 90% of the people believe they have to use substandard ATF's like WS to keep the warranty.
MORE TECHNICAL INFORMATION
Synthetic D6 ATF is a lower viscosity version of the D4ATF and is designed for better fuel efficiency in CAFE testing. Dexron VI requires a different approach to a conventional ATF formulation. Rather than beginning with a 7.5 cSt fluid and allowing a viscosity loss in use to drop to 5.5 cSt, the Dexron VI fluid requires a starting viscosity of less than 6.4 and a final drop to no less than 5.5 cSt. Red Line D6 will drop to no less than 6.1 cSt. Since the final viscosity after use of these fluids are similar, Dexron VI fluids can be used where Dexron III fluids
were previously recommended (with the exception of some manual transmission applications, our customers report).
D6 ATF also provides significantly improved gear protection and will provide a GL-4 level of gear protection. The balanced frictional characteristics provide smooth and consistent shifts for extended drain intervals. The superior stability compared to petroleum ATFs allows high-temperature operation without varnishing valves and clutches which leads to transmission failure.
Popular product and application crossover:
Dexron® VI (GM #88861003), Mercon® SP, Mercon® LV, Mercon®, Dexron® III '99 on automatic applications
BMW - Dexron® VI - BMW #83 22 0 432 807, 83 22 0 397 114
('06 on 6L45E X3, 6L809E, '07 on 3 Series, '08 on 1 Series with GM GA6L45R 6 speed automatic)
Ford Mercon® SP - XT-6-QSP
(Torque Shift 5-speed Automatic 5R110W, '03 on 6.0 liter diesel trucks, 2005-09 V-10, ZF 6HP26 6R60/6R75)
Ford Mercon® LV - XT-10-QLV
('08- Focus, '09- F-150, F-250SD, Expedition, Navigator 6R80)
Honda/Acura DW-1, Acura ATF Type 3.0
Mercedes Fuchs/Mobil/Shell 3353, MB Sheet 236.12 (NAG-2, 722.9,
7 speed transmission - MB # A001 989 45 03 10)
Mercedes Mobil/Shell ATF 134, Fuchs/Titan 4134 (MB Sheet 236.14 NAG-2, 722.9 7G-Tronic supersedes 3353, MB # 001 989 68 03 10)
Mercedes - Dexron® VI MB Sheet 236.41 (722.550 8 speed
ML Class hybrid type 164.195)
Mitsubishi Dia Queen ATF-J2, Mitsubishi # 4040610, 4031610
Mitsubishi SP-IV - Hyundai SP-IV - Kia SPH-IV
NissanMatic S
Toyota/Lexus WS, AW-1 - JWS 3324, NWS09638
(VW/Audi 0C8 8 speed # G 055 540, SAAB '03 on 9-3 6 speed # 93 165 147, Volvo # 31 256 774, 31 256 775)
ZF Lifeguard 6 & 6 Plus - Shell M1375.4
('02 on 6 & 7 Series, '06 on 3, 5 Series and X5 with ZF 6 speed automatic BMW# 83 22 0 142 516, 83 22 0 144 137, 83 22 0 406 929, VW/AUDI # G 055 005, G 055 162 )
ZF Lifeguard 8 - Shell M-L12108
(BMW # 83 22 2 152 426 and VW/AUDI # G 060 162)
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