Could you recommend the best fluids for a 2006 F150 4x4 V8 for the:
Is Amazon a reliable place to purchase these fluids? Does the rear differential come with a pre-made gasket?
Are there any other oil or fluid changes you’d suggest?
Thanks!
Make sure to change the front differential too. I have already changed the rear axle, transfer case, and engine oil/filter. I used Permatex gear lube RTV instead of a gasket since I’m not sure if you can get one for an ‘06—RTV ensures there won’t be any leaks.
Next, I’ll be changing the front differential gear lube using a vacuum evacuator. I have Amsoil in the rear differential and transfer case. I just finished the rear brakes and replaced a faulty right differential seal. While doing that, I drained the rear differential gear lube and also replaced the left rear seal.
I’m planning to switch out the transmission fluid with about 16+ quarts of Amsoil as well.
Costco, Walmart, and Amazon all sell synthetic engine oil under their house brands, which are made by Warren. It’s a good value for the price, though there are higher-quality oils available that will cost more.
It’s a good idea to change the brake fluid too, or you can use an inexpensive brake fluid tester to check the moisture levels in the fluid.
My 2012 manual says you can use 75w-140 instead of 75w-90 for the rear. My front requires 75w-90, but I plan to use 75w-110.
I checked the Amsoil site for your 2006 with the 5.4 engine, and it recommends 75w-140 for the rear axle. In fact, it suggests 140 weight for the 9.75, 8.8, or 10.25 axles.
However, when I checked the weight for my daughter’s 2015 Expedition, I found different recommendations depending on the source. If you have the owner’s manual, it should specify the correct weight. For her Expedition and my F-150, they give you the option to use 140 weight for the rear.
I prefer to let the RTV cure overnight before filling. In the past, I would apply RTV and fill immediately, but most RTVs now recommend waiting.
For oil Castrol mobil or royal purple.
I used to use pennzoil until a friend asked me to check my dipstick after a week of driving with pennzoil , it was black, he suggested I use Castrol after a week of driving, after 3 months the oil was still a nice light brown