I use 5w20 royal purple but its a little expensive. If you change your oil regularly, in my opinion any synthetic oil(except maybe generic brands) oil will protect you just fine.
I'm using Mobil 1 and it's worked great for me. I want to try out RP on one of these oil changes. Yes you can find a 5qt jug 5w-20 at wal-mart, that's what I got recently.
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2003 Mustang GT Fobra, Sonic Blue 4R70W 262rwhp/280rwtq - Mods in profile Vortech coming soon.....
Daily Driver 2001 Mustang V6, Oxford White 4R70W
Mods in profile
Motorcraft 5W20 full synthetic or the Motorcraft synthetic blend and a Motorcraft FL-820-S is your best and cheapest bet it's what I used and Not because I get it for free either
3.73 gears, BBK cai,BBK Throttle body and plenum, BBK long tubes with x-pipe, flowmaster 40's, steeda pully's, steeda's tri axle shifter, diablo predator, spec stage 1 clutch,spec aluminum flywheel, crossed drilled rotors front and back, ford racing springs
I have 107,367 miles on my car. All oil changes were with Mobil 1 and Mobil 1 filter. The oil was from Walmart in 5 qt jugs and as was mentioned runs about $22-$23 a jug. I buy 2 jugs every three oil changes. It's the cheapest place I've found.
I used to use Mobil 1...till I realized I was spending all that money on an oil that was not full syn...now I use only Royal Purple...i can tell a huge dif...in the way my car runs...every year hot rod magazine has an engine build off...this year 25 outta 28 used Royal Purple if that tells ya anything!!!
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1996 Gt 5spd.
pi conversion heads ported, comp cams, 24lbs injectors, pro-m mass air meter, bbk cold air, livewires, screamin deamon coils, bbk lowering springs, pro 5.0 shifter, mac lower and upper control arms, kyb front and rear shocks/struts, centerforce dual friction clutch, frp shorty headers, upper plenum ported, frp 70mm throttle body, frp 3:73 gears, straight pipes, 17x9 front by 17x10.5 rear cobra r's 310hp and 315foot pounds of torque!
might be true this year charlie, wasnt so awful long ago there was a large consensus of engine builders swearing by slick 50 as well. as far as mobil 1 not being full synthetic id like to see where you got that info, besides royal purples own marketing.
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2003 Mustang GT. diablo sport tuner . CAI , 3.90 gears, Steeda Tri-ax shifter, BBK LT headers and magnaflow exhaust.