Limited slip / LS Mobil 1 fluid

[chrisd0729]

Damn, just finished swapping gear oil in my 77 with stock 9" rear and noticed the bottles are stamped LS And have limited slip friction modifiers included. Feel like an idiot, didn't even look for this at first and not sure if I need it.

1. how do I know if I need the friction modifier's?

2. If I don't need them, do I need to drain and refill again? Pumping this fluid out was a b!tch !

 

[bmc69]

If you don't have an LS, the presence of the friction modifier will have zero effect on anything.

 

[B RON CO]

Hi, X2. To tell if you have limited slip or open rear, jack up your rear axle and put it on jackstands. When you are in neutral spin a rear tire by hand. If the other tire spins the same way you have limited slip. If it spins the opposite way you have an open rear. You could also de-code your vin but a PO may have made changes. Good luck

 

[Nickm1024cobra]

Damn, just finished swapping gear oil in my 77 with stock 9" rear and noticed the bottles are stamped LS And have limited slip friction modifiers included. Feel like an idiot, didn't even look for this at first and not sure if I need it.

1. how do I know if I need the friction modifier's?

2. If I don't need them, do I need to drain and refill again? Pumping this fluid out was a b!tch !

Just leave it in there. Its not going to hurt anything.

 

[blubuckaroo]

It won't hurt a thing. I've seen the stuff used in transmissions and sometimes even in transfer cases.