mann777

Hi, need some inputs, Just want to know whether a change from stock OEM Toyota LSD gear oil to Mobil1 would make difference.

I also would like to switch over to synthetics in my diffs and transfer case and I have a couple of questions.

1. Do any of the drain or fill plugs have gaskets that need to be replaced? I know few Toyota models had "crush" gaskets on all the drain and fill plugs on both diffs, the transfer case and the transmission.

1. Are any difference to the Gear performance other than what Toyota delivers or Mobil advertises.
2. Now coming to the Manufacturers Toyota product is GL-5 SAE 75w-90. This is what the rear differential calls for.Check and Replace is Every 30,000miles. But Mobil1 is 5000 miles. I know Blue Purple specs are the closest to Toyotas, wanted your point of view.

3. Now coming to Mobil1 makes the GL-5 SAE 75w-90 but not the single viscosity SAE 90. Any suggestions on the synthetic version for the rear diff? Is the 75w-90 compatible with the rear diff?

4. What type/brand of LSD additive (friction modifier) or is it pre-mixed in the OEM ones ( toyota LSd oil) Is it the Hypoid gear oil for limited slip differentials API GL-5

I have heard of some toyota SUV who have got the change done to Synthetics have got slight moan out of rear diffs. And only on persistence the dealers have added pre-additives. This silences the whole groan coming out of rear diffs when in tight turns.
I plan to do it myself, but B4 i do then I need some heads up on these issues.

thanks

mansito

Not sure if my answer will help with your Mobil1 question. I just got my GX470 a month ago, and I have not yet looked into replacing the differential oil. But I've use RedLine Oil in my other cars with very good results. You can call RedLine customer service. They will connect you to an oil engineer. You can talk to the engineer, and he will tell you the best oil for your particular needs. I've used their oils in my cars' manual transmissions and differentials, and I've been very happy

jditom

I have switched my GX and Landcruiser to M1 75/90W for all diffs and t-case. I have not noticed any difference. It is just piece of mind.

The T-case uses allen bolts so I bought the same ones from my Toyota dealer to put on my diffs. Allens are so much easier to get off then those shallow nuts.

mann777

Was there any gasket or "O" ring inner side for replacement.

jditom

I believe all of them had some type of metal crush ring. I believe the front diff was larger and copper. Any Toyota dealer will have them on the hand.