hello all I want to do a dif oil change as well as trans oil change but I do not know how to find out if I have a lsd so I can use SAE 90 ,or w/o I will use 80w90
can any of you help me? and how good is royal purple? getting the car ready for sale so need to get it done ASAP .

thank you for all of your time and help.

 

No verts came with LSD AFAIK.

 

Only Turbos came with LSD, from the Sticky of options.

Still in doubt? try this:
Jack up the back end enough to freely spin a tire, then spin a tire.

IF:

If the opposite tire spins in the same direction, you have a limited slip differential.


If the opposite tire spins in the opposite direction, you have an open rear end.

 

thank you and how is RP?

 

^Do what Ryan123 said first.


These cars are old, maybe your lucky and at some point in the last 20 years someone swapped a lsd rear end into it.

 

see if the filler nut on the back of the Differential has a tag that says:use LSD type fluid only".
The spinning tire method is good too,.

 

^ That will be a nice treat and make someones day.

 

That information is not correct; the correct information (found in the Stickies) is that the following models had LSD:

86-88 GXL
87-91 Turbo
88 GTU
89-90 GTUs (however not the 89-90 GTU)

It is true that U.S.-spec convertibles did not have LSD.

 

make sure to let go of e-brake before spinning rear tires >.>.....

"89-90 GTUs (however not the 89-90 GTU)"
am i retarded, or is that a typo? cause it sounds like it's contradicting itself.

i'm stuck with an unlucky 89 GXL with no lsd either >.< cheap mazda bastards, woulda traded AAS for lsd any day...

 

You are retarded (although possibly only mildly).
The GTUs and GTU are two different models.

 

yup, that went right over my head, thanks