Originally Posted by bly109

Most high quality synthetics already have the additive in them.

Originally Posted by fireresqjeep

The dealer told my wife the same thing when she took the jeep in for a recall. They checked everything and went thru my maintenance log and noticed it was due for the diff. fluid change. They said they would be happy to do it and would only cost around $250! Luckily she remembered i had already bought the fluids and planned on doing it on the next oil change. If you do do it yourself make sure you get the additive for the rear-end which is only available thru the dealer as far as i know. It will cost between $4 and $10 depending on the mark up. Also the plugs have magnets on them to catch any metal shavings from normal wear. If you do notice any large shavings you may want to take the cover off and inspect your gears.

Originally Posted by Mark Doiron

I have a Lim Slip Diff. Is that the additive you're talking about? Or is there yet another additive? I just passed 15K miles, so I'm preparing to change my fluids.

Originally Posted by toad

OK..changing the diff fluid out is something you can do yourself ... Basically, you take off the diff covers, drain out the fluid, clean it out pretty good as well as cleaning the covers, put the "liquid" or lube locker gasket on, put the covers back on and screw

Originally Posted by Mark Doiron

I have a Lim Slip Diff. Is that the additive you're talking about? Or is there yet another additive? I just passed 15K miles, so I'm preparing to change my fluids.

Originally Posted by armycop

I don't know why you would pay someone when it is an easy do-it-yourself job. For a simple fluid change, just use a 3/8" extension and ratchet to remove the drain and fill plugs. If the oil looks murky or has strange particles in it, then just take the diff cover off and clean/check the inside. You are paying someone 45-90 bucks an hour to do something anyone can do with a drain pan and simple household tools. You can take the old oil to a Walmart or some auto parts stores take used oil. If you do it yourself, you can ensure quality products go in (I use Royal Purple), instead of the cheap stuff. 3-containers of Royal Purple @ $11.99 plus a small tube of sealant (if you take the covers off) is around $40. Plus you can learn something and be sure everything is torqued properly. If you use the right products, the warranty will not be voided. They can only void the warranty if you do something stupid and they can prove neglect, like leave the plugs off or forget to put oil in it.

Originally Posted by bly109

yes, thats the additive Im talking about. I know for sure mobil one has it in it and Im pretty sure Royal Purple and Amsoil does too. Check out their websites and look up gear oil, it will tell if it does or doesnt have the limited slip additive.

Originally Posted by fattygio

It says in the manual "Trac-Lock" requires additive

Originally Posted by toad

How did I know SOMEONE was going to say SOMETHING in that regards

And when the dealer told me that I needed the diff. fluid changed, and how much it was, I told him I was going to do it myself. They said oh ok..just keep the receipts for the warranty.

Originally Posted by fattygio

It's not that I CAN'T do it.. i'm concerned about voiding warranty.. say I have a problem down the road, they could give me the run around couldn't they? Show them a receipt for some diff oil??