« on: Feb 21, 2015, 10:18:58 AM »
Interesting, i would like to hear Aisin's stance on it as there's so much internet hearsay out there on this subject. I found one thread where a dealer was putting 10W-30 in these transmissions, and other threads saying that the gl-5 was a typo blah blah blah....
The challenge i have is if i even want to run gl-5 gear lube in the trans, its damn near impossible to find stuff without the limited slip additive in it at the stores.
As for the dual cases i run full synthetic either mobil 1 or castrol syntec 75-140 and fill up the front case and let it soak through.
Putting 10w-30 in a transmission almost sounds criminal. Motor oil and gear oil are not at all the same in formulation. The pressure loads that rotating gears have require different additives than a combustion engine does. That dealership would be off my list!
When my dual adapter bearing blew up I put a bunch of motor oil in the t-case to get it home the. Had it towed in to the shop for repairs. It was so hot that I just wanted volume.
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1989 4Runner: Dual Ultimate (Inchworm front & Marlin 4.70 rear), Marlin Twin Stick, 1200-lb clutch, 4.88 R&P, Aussie Front, Detroit rear, 30-spline Longs, Long hub gears, ARP hub and knuckle studs & 35x12.50 Cooper STT PRO tires. Marlin rear bumper & sliders. FROR front bumper. SAS with Alcan springs & Rancho 9000XL shocks. Budbuilt Bolt-on traction bar. Custom Interior Cage by Those Guys Rod and Customs.
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