So I went to change the front and rear gear oil and I used quaker 75/90 synthetic gear oil.....will this type of oil be ok????? Or will it harm the ATV

 

HUGE mistake. Drain both ends now.

Use the special Polaris fluid in the front and Castrol Syntec 5w50 oil in the rear.

You may have to change the front a couple of times now. ALL traces of the 90 weight must be removed from the front so the 4wd will work correctly.

 

The front diff uses AWD Hillary fluid and the back uses tranny fluid. I use sthythetic chain case oil for the tranny. 90 Weight gear goes in neither.
Only Polaris with the locking hubs 2003 and down, use gear oil in the front diff.

 

my bad...glad I didn't drive it!!! I guess its off to the polaris dealer I go this week!!!

 

There is no separate rear diff on the SP500, its more like a tranny/rear diff, all in one combo. Thats why the rear takes no gear oil.

 

If you don't have access to the correct Polaris fluid for the front 5w20 synthetic motor oil will work for a while with no damage to anything.