Engine Oil

Oil+Filter changes are an often neglected, greasy, lowly task, however they do preserve & extend a vehicles life. For vehicles or engines under warranty, best to Use+Document OEM spec Fluids+Filters+ServiceIntervals, so to not void that consumer protection. For a new vehicle\engine, changing all fluids & filters after the first ~100miles & again at 1000miles is recommended to clear away particulate generated during BreakIn, then routine 5k~10k mile ServiceIntervals should be followed & adjusted for severe conditions. After factory warranties have expired, opinions & preferences do vary; for this 2001.Ford.ExST, any warranty lapsed many Miles\Years ago & thus the Oil+Filter+ServiceInterval are now as noted below, adjusted for duty, some technical improvement & preference.

The Factory\OEM OwnersGuide Oil spec for this engine is 5quarts of Ford# 5w30.Blended made by Conoco.
Considering the notorious OilPressurized TimingTensioners in this engine & its snow plowing service in winter,
after the warranty expired, I switched to using 0w20.FullSyn Each Autumn & 0w30.FullSyn Each Spring.
YearRound I'd use 0w20 in colder climates , 0w30 in more typical climates , 0w40 in extremely hot climates.
Proudly being a CheapBas'ard, the usual choice is the least expensive brand at WalMart, labeled compliant with
AmericanPetroleumInstitute\API, SocietyAutoEngineers\SAE & InternationalLubeSpecApprovalCommittee\ILSAC.

The Factory\OEM OwnersGuide Filter spec for this engine is a Ford#fL820s\f1az-6731-bd made by Purolator.
Oil Filters with 0.750"Diam*16tpiThrd are typical on V6~4.0L~SOHC SubAssemblies dated ~2000May17\Before.
Oil Filters with 22mmDiam*1.5mmThrd are typical on V6~4.0L~SOHC SubAssemblies dated ~2000May18\After,
as it is for my engine built 2000Aug18. Below are specifications & debatable opinions on three Filters I've used:

Tools+Supplies Required

BoxEndWrench\Socket+Rachet For 14mmDiam*1.5mmThrd*20mmLong*13~17mmHxHd DrainBolt
Oil FilterStrapWrench\OffOnly For TightSpace: GearStrap \ ModifiedStrap
WheelChocks, Jack, JackStands, ShopRags, AbsorbantLitter, ReCycleContainer, CatchPan
Oil DrainWasher: Ford# f77z-6734-ab Swapped To 1/8"Slice Of 1/2"ID Fuel\Oil\Heater Hose
Oil Filter: Purolator\Ford#fL820s Swapped To K&N#hp2011, 22mmDiam*1.5mmThrd
Oil 5qts: 5w30.Blended Swapped To 0w30.FullSyn Each Spring & 0w20.FullSyn Each Autumn
Optional Oil DrainValve 14mmDiam*1.5mmThrd To Ease Future OilChanges: Fumoto#f106n

Oil Change+Filter Procedure

Remove Oil FillCap
Remove DrainBolt; Allow Oil To Fully Drain
Clean+Inspect DrainBolt+DrainWasher
If DrainWasher Is Worn\Damaged, Replace With 1/8"Slice Of 1/2"ID Fuel\Oil\Heater Hose
Install DrainValve If Replacing DrainBolt, Otherwise ReInstall DrainBolt
HandStart Then WrenchTight Max19ftLb, Do NOT OverTighten
Remove Old Filter, Use OffOnlyWrench\Strap If Needed
Make Sure Old RubberSeal Comes Off With Old Filter
Wipe Down Filter Seat+Threads & Around DrainBolt With A Clean ShopRag
Wipe New Filter RubberSeal With Clean Oil
Install New Filter; HandStart+1HandTight+2Hand90deg, Do NOT Use OffOnlyWrench\Strap
Fill Engine With 5qts Of New Oil Then Replace FillCap
Start+Idle Engine 5min Then 30min CoolDown
Check DipStick & For Leaks; Tighten Filter+DrainBolt\Valve If Needed, Add Oil If Needed
After 1st Drive & 30min CoolDown Again Check DipStick & For Leaks

EngineColdStart Procedure

When a V6~4.0L~SOHC Engine hasn't run for 12 hours or longer, this EngineColdStart routine is recommended
for general PreLubrication of the Engine critical components & specificly to PrePressurize the TimingTensioners.

Turn Key To RUN Not START, Let InstrumentCluster Lamp+BuzzerTest Complete
Push+Hold GasPedal To Floor, InstrumentCluster OilPressureNeedle Should Be At Zero
Turn Key To START, Let Engine CRANK Without Starting Until OilPressureNeedle Moves Or ~10secs
Release GasPedal, Let Engine START, Then Allow Key To SpringReturn To RUN
InstrumentCluster OilPressureNeedle Should Quickly Rise+Hold At MidGage Position