On the Royal Purple website, they have republished an article from: fordtruckworld.com http://www.royalpurple.com/ford-truck-world.html

The writer claims the following:

We used Royal Purple Motor Oil 5W30 in the engine, Max ATF in the transmission, and 75W90 Max-Gear in the differential. After everything was changed, we duplicated our MPG testing. The truck had been getting 14.8 MPG and after the change to Royal Purple, we are now getting 15.9 miles per gallon. That’s a 1.1 mpg increase and an overall 7.4% increase in mpg.

Now my question is this:

How much of this stuff do I need to buy? How many bottles, quarts, liters, gallons, et cetera, of the gear oil and transmission fluid?

I've never owned a car where I had to change out those fluids.

 

Using synthetic fluids will help a bit with the fuel efficiency of your vehicle. However, Royal Purple Max Gear is not worth the money you are paying for it. RP 75W90 Max-Gear failed several tests according to One Automotive Gear Study.

-Viscosity Before and After KRL 20-Hour Shear Stability Test.
-% Viscosity Change from Shear Test.
-Brookfield Viscosity@ -40°C (-40°F) for 75W-90.
-ASTM D-130 Copper Corrosion (API GL-5).



Here is a link to the study I mentioned.

http://www.performanceoiltechnology....te%20Paper.pdf

 

Switching all lubricants over to full synthetic can give you a SMALL increase in fuel economy. Motor oil will probably have the biggest factor - any improvement with ATF will be negligible, and the rear diff has been factory filled with synthetic for several years now. Note that 75W90 has NOT been an approved grade for the rear for a while now and the suggested motor oil grade is now 5W20.

 

American Muscle has a pretty good price for Royal Purple.

What I would like to know is this:

2007 F150 4.2L V6

How much of the ATF & gear oil will I have to order?

Does anyone have experience with the coolant? How much of that will I need to order?

I don't want to start the job, and then not have enough. Or order too much of that stuff - i.e. 1 case of ATF when I only need a few quarts.

http://search.americanmuscle.com/?qu...ustangtunin g

http://search.americanmuscle.com/?qu...g=mustangtunin g



Royal Purple 5w20 Motor Oil $6.49
Royal Purple� Motor Oil is a tough, long life, high performance oil that delivers superior protection and enhanced performance to engines. It gains its performance advantages ...

Royal Purple 'Purple Ice' Super Coolant $11.99
Purple Ice� is a high performance, synthetic, radiator coolant additive for engines. It is formulated to reduce the surface tension of the coolant, which improves heat transfe ...

Royal Purple Synchromax Manual Transmission Fluid $9.99
Synchromax� is recommended for manual transmissions that specify an automatic transmission fluid or motor oil. Synchromax� is formulated with Royal Purple's synthetic, propri ...

Royal Purple Max Gear 75w90 Gear Oil $10.99
Max-Gear� is an ultra-tough, high performance, GL-5 automotive gear oil designed to provide maximum protection to heavily loaded gears while maximizing power output throughout ...

Royal Purple Max ATF Transmission Fluid $9.99
Max ATF� is a synthetic, high performance, long life, multipurpose, transmission fluid. Max ATF� is recommended for all transmissions requiring Ford Mercon� or GM Dexron� III ...

 

Capacities are listed in your owner's manual.