Rear Differential Fluid

Not a big deal, but I'd recommend just using the nozzle on the bottle and skip the pump. Seems cleaner and less of a hassle that way. In the past I used a pump but only because I was using a 1 GAL jug w/o nozzle of gear oil that required it. In the future I'm planning on just using the 1 QT bottles w/nozzle.

 

I was thinking a piece of poly tubing attached to the bottle, like a 75-90w IV.

 

I have the shudder on the turn also - 09 4-cyl with LSD button. 195k mi. will try change with additives... I also have larger diam tires on there. Could tha hurt diff from more torque?

 

Do you mean the rear differential lock button? The Tacomas that came with actual mechanical limited slip differentials don't have a button for it. You have a TRD OR or TRD Sport?

Either way, additives are not needed for the rear diff lock or the non-LSD diffs. Won't hurt anything to use them but it won't solve anything either

 

2009+ trucks came with an open differential.
They had Auto-LSD. It uses the brakes as a LSD.
Additives won’t hurt it, but I see no reason that they would help it either.

 

Actually it is possible to have the LSD and a Locker in the same differential case. My 2005 Jeep Rubicon most certainly has a geared LSD and an air locker:



Alas, Toyota did not provide such a thing for the Tacoma.

 

I have this rear :

Thoughts on the fluid or additive I should use? It's an 09 base model but has these:

 

2009+ trucks all had an open differential.
The brakes were used to simulate a mechanical LSD.
You do not need any additives.
A lot of fluids will have the additives already in them. You can still use the fluid, the additives won’t help any, but they won’t hurt it either.

 

So when I accel hard from a stop making a turn and I hear a chattering or bumping in the rear end, that is my brakes?

 

It could be in the read end, but the noise isn’t caused by the clutch packs.
Your differential doesn’t have clutch packs to chatter.
I’d have to be there and experience the noise myself to help further.
I’ve never heard of the AutoLSD chattering, bumping maybe. Because the brake are pulsed when AutoLSD is active.

 

you have a bad U joint? mine use to clunk and bang found chunks missing from my caps

 

If I had to call it, I would say this does sound like a bumping. I will also check the u-joints. Great advice and thank you. I should also point out that when I turn off auto LSD I don't hear the noise.

 

Then I’d would say it the brakes.
Sounds good and normal too me.

 

No. That's either the rear diff fluid degraded or the rear diff on the way out mechanically. Try replacing the fluid with something thicker (like 85W90 non-synthetic or 75W140 synthetic) and see if the chatter goes away.

The drained old fluid can also give evidence of mechanical failure, if you see pieces of metal come out or if the fluid looks like a shiny metal slurry. Had the rear diff fail mechanically with two people in my Toyota off-road club. Not sure about the root cause, but replacement third members or even complete axle assemblies are reasonably affordable from salvage yards shown on Car-part.com.

If the brakes engage for VSC or traction control, you'll hear the ABS module making weird noises. For your trim, the ABS module is in the engine bay, in front of the firewall on the passenger side.