[Edits to follow - work in progress]
Where to find the 4.0L SOHC:
1997-2010 Ford Explorer/Mercury Mountaineer
2001-2010 Ford Sport Trac
2001-2010 Mazda B4000
2001-2011 Ford Ranger
2005-2009 Land Rover LR3
2005-2010 Ford Mustang
2006-2010 Ford Sport Trac
For us, this story begins in 1997 with the first of the 4.0L SOHC engines being sold in the Explorers. Ford used a "Rocker Arm" part number F77Z-6564-AB in the first of the SOHC engines (1997-1998ish), which was very similar to the follower used in the 4.6/5.4L 2v and 4v motors, but with no oiling hole.
Original 4.0L SOHC "Rocker Arms" (cam follower)
This is the oiler feed line [part 6578 above] and this is an indicator of an early 4.0L SOHC (1997-2007ish).
These engines have followers with NO oiling hole from the valve adjuster ["lifter"] - see the top picture.
**I REALLY cannot stress this point enough...
Some time in 1998, the F77Z-6564-AB was deprecated and the YL2Z-6564-AA was the authorized replacement for ALL early SOHC engines (with the oil feeder line on cam towers). The F77Z part was prone to flexing and could jump off the adjuster and even has been known to break the Cam Position Sensor finger off the camshaft:
Again...
(There will be a test later - seriously.)
Here is an edited image found on the Interwebs that compares the side profiles of the F77Z and the YL2Z and GT (see below)
GT Super Car, GT-500 Followers:
On the Left is the follower from my 2005 Sport Trac (90 grams), on the right is the GT SuperCar/GT-500 follower 4G7Z-6564-AA or Ford Racing M-6529-MSVT (90 grams) - difficult to see, but there is a TINY oiling hole on the right follower. These followers are also hardened (like the YL2Z) so there is less flex and wear.
The "GT/GT-500" followers are found in the following:
2005-2006 Ford GT Super Car
2007-2010 Ford Explorer/Mercury Mountaineer
2007-2011 Ford Ranger
2007-2010 Mazda B4000
2007-2010 Ford Mustang 4.0L
2007-2010 Ford Sport Trac (Gen2)
2007-2014 Ford 4.6L 2v/4v, 5.4L, Shelby
[Note - The 2007 dates are possibly all "Mid Year" as I have spoke to a couple 2007 Sport Trac owners that had an oiling rail.]
And finally, the "Big Dog"! The Jesel Ford Modular Follower - FULL ROLLER.
So, here are your options by year...
1997-1998 engines with the F77Z followers here are your choices:
1. Upgrade to the YL2Z for a stiffer, heat treated follower that may actually increase reliability and a few HP to boot (no flex at RPM).
2. Upgrade to the Ford GT Supercar/GT500 Roller Rockers/Followers or the Ford Racing M-6529-MSVT (IDENTICAL to the YL2Z - but has a cam lobe oiler).
3. Upgrade to the Jezel Ford Modular followers (@ $125 ea!) for some guaranteed HP.
1998-2007ish (All with cam oil feeder tube):
1. Use the factory YL2Z follower as a factory stock replacement.
2. Upgrade [tiny] to the Ford GT Supercar/GT500 Roller Rockers/Followers or the Ford Racing M-6529-MSVT (adds cam lobe oiler).
3. Upgrade to the Jezel Ford Modular followers.
2007ish-2011 (All without the cam oil feeder tube, and followers with oiling holes):
1. DO NOT USE any follower without an oiling hole!
2. Use the Ford GT Supercar/GT500 Roller Rockers/Followers or the Ford Racing M-6529-MSVT (has cam lobe oiler) if the price is right.
3. Upgrade to the Jezel Ford Modular followers.
Where to find the 4.0L SOHC:
1997-2010 Ford Explorer/Mercury Mountaineer
2001-2010 Ford Sport Trac
2001-2010 Mazda B4000
2001-2011 Ford Ranger
2005-2009 Land Rover LR3
2005-2010 Ford Mustang
2006-2010 Ford Sport Trac
For us, this story begins in 1997 with the first of the 4.0L SOHC engines being sold in the Explorers. Ford used a "Rocker Arm" part number F77Z-6564-AB in the first of the SOHC engines (1997-1998ish), which was very similar to the follower used in the 4.6/5.4L 2v and 4v motors, but with no oiling hole.
Original 4.0L SOHC "Rocker Arms" (cam follower)
This is the oiler feed line [part 6578 above] and this is an indicator of an early 4.0L SOHC (1997-2007ish).
These engines have followers with NO oiling hole from the valve adjuster ["lifter"] - see the top picture.
**I REALLY cannot stress this point enough...
Some time in 1998, the F77Z-6564-AB was deprecated and the YL2Z-6564-AA was the authorized replacement for ALL early SOHC engines (with the oil feeder line on cam towers). The F77Z part was prone to flexing and could jump off the adjuster and even has been known to break the Cam Position Sensor finger off the camshaft:
Again...
(There will be a test later - seriously.)
Here is an edited image found on the Interwebs that compares the side profiles of the F77Z and the YL2Z and GT (see below)
GT Super Car, GT-500 Followers:
On the Left is the follower from my 2005 Sport Trac (90 grams), on the right is the GT SuperCar/GT-500 follower 4G7Z-6564-AA or Ford Racing M-6529-MSVT (90 grams) - difficult to see, but there is a TINY oiling hole on the right follower. These followers are also hardened (like the YL2Z) so there is less flex and wear.
The "GT/GT-500" followers are found in the following:
2005-2006 Ford GT Super Car
2007-2010 Ford Explorer/Mercury Mountaineer
2007-2011 Ford Ranger
2007-2010 Mazda B4000
2007-2010 Ford Mustang 4.0L
2007-2010 Ford Sport Trac (Gen2)
2007-2014 Ford 4.6L 2v/4v, 5.4L, Shelby
[Note - The 2007 dates are possibly all "Mid Year" as I have spoke to a couple 2007 Sport Trac owners that had an oiling rail.]
And finally, the "Big Dog"! The Jesel Ford Modular Follower - FULL ROLLER.
So, here are your options by year...
1997-1998 engines with the F77Z followers here are your choices:
1. Upgrade to the YL2Z for a stiffer, heat treated follower that may actually increase reliability and a few HP to boot (no flex at RPM).
2. Upgrade to the Ford GT Supercar/GT500 Roller Rockers/Followers or the Ford Racing M-6529-MSVT (IDENTICAL to the YL2Z - but has a cam lobe oiler).
3. Upgrade to the Jezel Ford Modular followers (@ $125 ea!) for some guaranteed HP.
1998-2007ish (All with cam oil feeder tube):
1. Use the factory YL2Z follower as a factory stock replacement.
2. Upgrade [tiny] to the Ford GT Supercar/GT500 Roller Rockers/Followers or the Ford Racing M-6529-MSVT (adds cam lobe oiler).
3. Upgrade to the Jezel Ford Modular followers.
2007ish-2011 (All without the cam oil feeder tube, and followers with oiling holes):
1. DO NOT USE any follower without an oiling hole!
2. Use the Ford GT Supercar/GT500 Roller Rockers/Followers or the Ford Racing M-6529-MSVT (has cam lobe oiler) if the price is right.
3. Upgrade to the Jezel Ford Modular followers.
