LSD Diff question

I have an 05 TRD sport (supposedly)and Im thinking that my rear diff is not a limited slip or has worn out or something but I dont really know how to test it other than to go do a burnout.
When its raining I get a lot of my passenger side rear wheel spinning when taking off with a little too much throttle.
It seems like one time in the rain I could feel it kind of bounce back and forth between rear wheels fighting for traction but mostly feels the same as my 91 did with an open diff. It has never felt like both rear wheels were locked up but Ive never driven anything other than with an open diff.

Heres a picture.

 

never changed the fluid. its on the to-do list but Im not sure what kind to get. Will the LSD additive hurt a regular diff?

I figured it would spin one wheel and then kick in but I've never experienced any "kicking in" you know... Unless its just really transparent to the driver.

 

is that a sticker? what does it say?

 

Is it possible that the LSD effectiveness could return with a fluid change?

 

The sticker is worn out and you cant tell what was printed on there.

 

I dont see how it could not be a trd sport model since it had the hood and color matched everything, bilsteins and outlet in the bed. Unless 05's were just weird with the models.
Is there a vin checker that denotes sr5, trd, etc?

 

The sticker say use LSD oil only

 

Only the Sports have the fake hood scoop... Hood Scoop, 2005-2008, then it is a LSD and add the LSD modifier. How could you have gone 6 years and not changed the oil? Wow, what a great truck for not brealing down... right?

 

So the LSD additive wouldn't hurt an open diff would it? Im going to go ahead and change the fluid this weekend. Im sure its nasty in there.

 

I've had the truck for 6 months.

 

Is that not the fact Christian... do other models other than a Sport come with it, huh?

 

That little sticker is the same size/shape/proportions as the one on mine that says ONLY LSD OIL, except rotated 90 degrees. Just an observation, take with it what you will.

 

Well then, it may have been serviced then...

 

Do Sport hoods only fit on Sport models?

 

The fake Hood Scoop is HOW you can tell if it is a SPORT. DERPMAN

 

nope. Sold mine for a regular hood. so theres plenty of non sport models rocking the scoop.

 

Should be seeing this. I know your diff is dirty and weathered, but i'm not really seeing the sticker. Keep in mind vehicles sometimes do odd things, I don't have a TRD but do have the LSD. Just an option to keep in mind. Also I don't see that the Additive would hurt the open diff. So to be safe you could just add it.

 

Im pretty sure that the LSD oil only sticker is on the the SR5's even if they don't have the LSD

 

You can jack up the back end to see if it is still strong. If your limited slip is still working well you can spin the tie on one side and it will spin the other in the same direction, an open diff will spin the other tire in the opposite direction. Other than that looking in the diff will tell you for sure or taking the vin to the dealer may be able to determine but I am not too sure. Good luck with it though. JOE>