doing gear swap anything else i should have them do while there in the diffs? special fluids? anything going from 3.73 to 4.30

 

Use amsoil differential fluid.

It touts a 5 % increase in fuel mileage.

I have a 2000 Ford Explorer, and when I made that change I got a little more than
5 % fuel economy when on the highway. It was negligable in town. I did that about 40,000 and it is still going like new at 350,000 + miles.

http://clik/to/My2000FordExplorer

 

Where di you get the 4.30 and what did you have to pay for them ?

 

I am lost.

I have a 2000 Ford Explorer

 

mtgrzlyman,

Do you have the OEM LS unit in the back? If so, make sure your fluids are the synthetics or it will destroy the diff. Either that or make sure to put in the friction modifier.

You may want to change the axle seals while your at it. You can get them at NAPA for a few bucks and it's good insurance to keep the crude out of you axle / diff.

I'm stealing a little bit o' knowledge from Fredvon4 on this one here; Ford recommends 8 oz of friction modifier in the rear end. Start with 2 oz and go to a parking lot and do a series of sharp turns. Add one ounce at a time until you get just a very slight amount of chatter in a sharp turn. The LS will grab better and not break away as soon when you off-road it. If you don't off road it, just use the standard 8 oz and be done with it.

 

Be sure to get the rear up to operating temp, as that has a substantial effect on the modifier doing it's job. The rear will grab more when warm.

 

Good point!