Differential oil

Hi im new here. Just had a question on diff oils . I called my toyota parts today to find out what diff oil to use in my 2008 tacoma l 4x4 long bed with lsd diff. They told me gl5 75 w 140 full synthetic. The question is does that sound right and do i need to add a friction modifier to the synthetic. Was thinking of using mobil 1 or royal purple. Having a issue of a rumbling at sharp turns. And have read on here that i need a bottle or 2 of additive.

 

I've been running the 75/140 in my diff. Hopefully someone will chime in about additive for yours..

This "rumbling" when you turn... have you ever lubed your driveshaft u-joints?

 

Is 2008 a real hydraulic LSD or is it the electronic simulated lsd?
In my 2005, I ran Valvoline 80W-90 high performance. No additive. Never had noise from the LSD.

 

Does it have an LSD sticker on the diff next to the fill hole? I don't remember when they changed from mechanical LSD to electronic, if you have friction plates (old style) I would use dino oil in it with the modifier ( just my PO).
If its old style and your getting a rumbling in corners, it might be that someone changed the oil and didn't use the additive, some jugs say its in the oil but don't believe it, use seperate additive.
When your done changing oil find a parking lot and do 6 or 7 figured eights to work the additive into the plates.

 

Some 2008's got true mechanical LSD's but not all of them. It's best to check for the sticker, option sheet from dealership or check to see which direction the wheels spin when up in the air.

In colder climates our specs for LSD diffs is: Hypoid gear oil for Limited-slip differential API GL-5 SAE 80W-90

If you live in a warmer climate and/or tow use the 75w140. Most synthetic gear oils don't require additional LSD additives.

I personally would use what your local dealership suggests.

 

I've used AmsOil Synthetic in a Ford limited slip differential which has the friction plates, I used a friction modifier. It word fine. This was awhile ago, friction modifier may no longer be needed with AmsOil, check their website.

 

Yes it has the lsd sticker on the rear end. I went ahead and called 3 different dillerships here in ga , all three said they use full synthetic gl5 75 w140 . So i ordered 3 quarts of moble 1 today off ebay fom pep boys for 10.75 a quart. Going to see how that reacts when i get it changed if it still acting up ill get a thing or 2 of the additive to add to it,and try that.

 

And to be sure you have LSD...

https://www.youtube.com/watch?v=T0DeTzQWNBQ

 

Per Toyota Tech Tip Bulletin #0078-11 regarding Limited Slip Differentials (LSD):

"The use of aftermarket LSD fluids or additives as a substitute for Toyota Genuine Differential Gear Oil LX 75W85 API GL-5 may result in damage to the internal differential components, and will contaminate the LSD clutch packs."
"When performing rear differential service on vehicle equipped with a mechanical LSD, be sure to use Toyota Genuine Differential Gear Oil LX 75W85 API GL-5 -- P/N 08885-02606."

To clarify, LSD-type rear diffs are NOT to be confused with a LOCKING diff, which does not use friction clutches but rather an electric solenoid actuator to "lock" both rear wheels together.

Now, I'll be the first to admit that OEMs almost always recommend their own house brands when it comes to fluids and lubricants. And, this stuff they recommend here is VERY expensive.
(Check your dealer.) But I have yet to find an exact equivalent that I can recommend to customers that does not pose some risk potential. I have seen Tacos come into the shop with differential "chatter", and without exception it was because the owner had allowed a different brand or type of lube to be used by him/herself or by his independent mechanic or lube shop.

So what say you, Taco owners? Can you vouch for a specific brand or type of diff lube that has worked for you in your LSD without any annoying or damaging results?

 

When I worked at an independent we used to use the AC Delco friction modifier on 05-06 Tundras and 05-08 Tacomas. Standard bulk 75w90 with a single additive with no issues for the 7 years I was there.



Now that I'm a dealer tech I only recommend OEM. It's less headaches.