I have a 2010 fx4 5.4. It has a 100,000 miles and I want to do some work to it. Firstly is change and or flush all fluids. What is BEST for trannie and diff? Also, it has a 7" ready lift and I want to replace rear shocks...any ideas? I am also adding new exhaust either flowmaster or magnaflo//// looking for a deep aggressive sound. Suggestions please. I have a k&N cai not yet installed. Enogh questions for now but more to come. Thanks in advance.

 

Best? Brand of fluid? Do what the manual says.

Exhaust is completely subjective, you'll really have to decide that for yourself.

Send back the K&N.

 

I cant help in all areas of your questions but I have a few suggestions
I use Scheaffers Lubricants they have a high moly content and I really like them. 75-140 in the rear and 80-90 in the front diff with great success I have 171,000 miles and every thing is still original no major breakdowns. I also use schaeffers supreme 7000 engine oil and motorcraft fl820s oil filter and had great luck but all fliuds are not created equal I think youll still enjoy other brand Mobil 1, Royal purple, liquimoly just to name a few I like scheaffers its what I use but by no means the only quality lubricant out there. I think picking a reasonable change interval and sticking to it is more important than seeking the ultimte in lubrication nirvana (I seen that statement in a forum once and liked it) an interval like the one in your manual will offer you the best success I change engine oil every 5000 and diffs every 60,000 because of my boat and potential water infiltration to my diffs so far so good.

As for the trans I stuck with the motorcraft mercon LV However this is one area of the manual I choose to disregard the change interval and I do it every 50-60,000 miles this maybe overkill but its cheap insurance to me and it gives me the warm and fuzzies. Others may disagree that thats not necessary or too often but it works for me and like I said its cheap insurance to know my filters clean and fluid is fresh for as often as I tow my 4000ish pound fishin rig 100 miles one way to the walleye.

As for the exhaust I have stuck to stock but we installed a MBRP cat back duals on a buddys similar rig and it had a nice mellow but boldish tone that wasnt overpowering or droney and hwy cruising may not be waht your after but it was a nice overall tone I thought.

As for the CAI ive heard bad things about power losses due to not sealing out warm engine bay air as effectivly as the stock box and current setup. You can search this out here its been discussed plenty.

As for shocks I stuck to stock on the rear Moog struts on the front I've heard great things about bilsteins again search this here been discussed plenty.

Good luck with your rig Sounds sweet and hope it all works out for you!!!

 

Tranny isn't needed unless you tow a lot, but you can drop the pan, change the filter, clean the magnet and then refill the 7 ish quarts with Mercon LV (double check the trans fluid type) if the fluid looks terrible, then consider a flush, but you might find yourself pleased after seeing the fluid is OK in color and not too much sediment on the magnet.

Consider changing spark plugs, but again take a look at them

Flush the coolant and refill with motorcraft orange (I think it should be done every 5 years or 100,000 miles, just my opinion)

Send back CAI, it's just noise and if you get a new exhaust, that might satisfy your need for a different sound.

 

Thanks for the replies. I was going to change plugs also. Is it worth the extra $ for iridium or is platinum fine? Surprised at the k&n comments, had one on my 07 and felt it helped? Never dynoed but truck felt like it had better response????