JLP 3" Lowering Shackles Installed (pics)
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From: Eastern TN
JLP 3" Lowering Shackles Installed (pics)
I installed a set of the Johnny Lightning Performance 3” drop rear shackles this weekend. The quality is top notch and the price was fair. Delivery had its issues, but I did manage to get them before the weekend was over.
For anyone contemplating a set of these, they level the truck perfectly. They are also very easy to install, if you have a floor jack and basic hand tools.
There were no instructions included with them, so I wrote my own for anyone interested. Please note that this install is referencing a stock 2004 Lightning. I’ve been told that the 2003 & 2004 Lightnings have more rear arch in the springs than previous years, but I do not know that for a fact.
01. Block and chock the front wheels so the truck cannot roll.
02. Break the upper and lower shackle bolts loose on both leaf springs.
03. Jack the rear of the truck up and support the rear axle with jack stands. Remove both rear wheels.
04. Look carefully at the angle of the driveline. Note that the driveshaft and pinion are almost perfectly aligned and straight. This will be important to remember later.
05. Raise the body of the truck by jacking it up from the frame (the towing package equipped trucks have an advantage here – just jack it up from the hitch). Raise it until the rear end is just about to lift off the jack stands. This will unload most of the spring tension from the factory shackles.
06. Remove the lower shackle bolt on the driver’s side. Pop the shackle out of its mount so it can swivel freely. If you use a long screwdriver to pry it up, you will lessen the chances of getting your fingers pinched.
07. Remove the nut from the upper shackle bolt on the driver’s side. The bolt will not slide out because the truck’s frame is in the way. Carefully lower the jack on the frame until the top of the leaf spring (and shackle bolt) clears the top of the frame. Remove the bolt and factory shackle.
08. Install the JLP shackle in the top of the leaf spring, being sure to orient it to match the factory shackle. Put the nut on the bolt and run it on until the bolt sticks through the nut.
09. Carefully raise the jack on the frame until you can slide the new JLP shackle into the lower mounting spot. Install the lower bolt and nut. Torque both upper and lower bolts appropriately.
10. Repeat steps 4-9 on the passenger side of the truck.
If you use the last hole in the JLP shackle (the one closest to the end), the truck should sit level. If you use this setting, the driveline angle for the pinion and the driveshaft will not be correct, and from what I’ve read, will cause vibrations in the drive train. Fortunately, there is a simple solution, built into your truck:
11. Now that your shackles are installed, lower the frame jack until the truck is resting on the jack stands.
12. Remove the two U bolts that attach the rear end to the leaf springs. Remove the top plate and set aside.
13. Loosen the center pin nut, on top of the leaf spring, several turns. You may find it necessary to compress the stack of springs with “C” clamps to remove the tension from the center pin.
14. Raise the frame jack until the rear end just raises off the jack stands.
15. The lowest plate of the spring stack is actually a tapered pinion shim. Using a screwdriver and a hammer, tap the side of the plate and spin it 180°. It will rotate on the leaf spring center pin. Line it up so it is straight and aligned with the leaf springs and tighten the center pin nut.
16. Using another jack, raise the rear end until it contacts the leaf spring. Install the top plate and U bolts. Tighten snugly and be sure to center everything up.
17. Remove the axle jack and then lower the frame jack until the rear end is resting on the jack stands. Torque the leaf spring U bolts appropriately.
18. Repeat steps 11-17 for the other side of the truck.
19. Note the angle of the driveline now that you have rotated the pinion shims. It should be almost identical to the original angle you noted in step 4.
20. Install the wheels, lower the truck and take a low speed test drive. Listen carefully for any vibration or noises coming from the driveline. If none are present, carefully accelerate up to 60 MPH or more, listening for vibration or noises. There should be none.
Congratulations !! You have lowered your Lightning without wrecking your driveline angles or ruining the comfort of your ride. Enjoy !!
Here's a couple pics of mine, before:
and after...
For anyone contemplating a set of these, they level the truck perfectly. They are also very easy to install, if you have a floor jack and basic hand tools.
There were no instructions included with them, so I wrote my own for anyone interested. Please note that this install is referencing a stock 2004 Lightning. I’ve been told that the 2003 & 2004 Lightnings have more rear arch in the springs than previous years, but I do not know that for a fact.
01. Block and chock the front wheels so the truck cannot roll.
02. Break the upper and lower shackle bolts loose on both leaf springs.
03. Jack the rear of the truck up and support the rear axle with jack stands. Remove both rear wheels.
04. Look carefully at the angle of the driveline. Note that the driveshaft and pinion are almost perfectly aligned and straight. This will be important to remember later.
05. Raise the body of the truck by jacking it up from the frame (the towing package equipped trucks have an advantage here – just jack it up from the hitch). Raise it until the rear end is just about to lift off the jack stands. This will unload most of the spring tension from the factory shackles.
06. Remove the lower shackle bolt on the driver’s side. Pop the shackle out of its mount so it can swivel freely. If you use a long screwdriver to pry it up, you will lessen the chances of getting your fingers pinched.
07. Remove the nut from the upper shackle bolt on the driver’s side. The bolt will not slide out because the truck’s frame is in the way. Carefully lower the jack on the frame until the top of the leaf spring (and shackle bolt) clears the top of the frame. Remove the bolt and factory shackle.
08. Install the JLP shackle in the top of the leaf spring, being sure to orient it to match the factory shackle. Put the nut on the bolt and run it on until the bolt sticks through the nut.
09. Carefully raise the jack on the frame until you can slide the new JLP shackle into the lower mounting spot. Install the lower bolt and nut. Torque both upper and lower bolts appropriately.
10. Repeat steps 4-9 on the passenger side of the truck.
If you use the last hole in the JLP shackle (the one closest to the end), the truck should sit level. If you use this setting, the driveline angle for the pinion and the driveshaft will not be correct, and from what I’ve read, will cause vibrations in the drive train. Fortunately, there is a simple solution, built into your truck:
11. Now that your shackles are installed, lower the frame jack until the truck is resting on the jack stands.
12. Remove the two U bolts that attach the rear end to the leaf springs. Remove the top plate and set aside.
13. Loosen the center pin nut, on top of the leaf spring, several turns. You may find it necessary to compress the stack of springs with “C” clamps to remove the tension from the center pin.
14. Raise the frame jack until the rear end just raises off the jack stands.
15. The lowest plate of the spring stack is actually a tapered pinion shim. Using a screwdriver and a hammer, tap the side of the plate and spin it 180°. It will rotate on the leaf spring center pin. Line it up so it is straight and aligned with the leaf springs and tighten the center pin nut.
16. Using another jack, raise the rear end until it contacts the leaf spring. Install the top plate and U bolts. Tighten snugly and be sure to center everything up.
17. Remove the axle jack and then lower the frame jack until the rear end is resting on the jack stands. Torque the leaf spring U bolts appropriately.
18. Repeat steps 11-17 for the other side of the truck.
19. Note the angle of the driveline now that you have rotated the pinion shims. It should be almost identical to the original angle you noted in step 4.
20. Install the wheels, lower the truck and take a low speed test drive. Listen carefully for any vibration or noises coming from the driveline. If none are present, carefully accelerate up to 60 MPH or more, listening for vibration or noises. There should be none.
Congratulations !! You have lowered your Lightning without wrecking your driveline angles or ruining the comfort of your ride. Enjoy !!
Here's a couple pics of mine, before:
and after...
Last edited by B-Man; Apr 21, 2004 at 08:00 PM.
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Joined: Jun 2003
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From: Paradise
Beautiful, and yes the '03 - '04's shall we say have a little more spring to increase payload numbers.................... unfortunately when you install the 3" drop shackles you add increased pressure to the rear suspension and you must relocate the anti-sway bar arms on the frame rails to relax the suspension...... believe me "been there done that" - it is really easy just measure up 2.5 inches on the frame railes drill new holes and reposition the arms, yes it actually works.
D-Day
D-Day
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Joined: Dec 2003
Posts: 1,182
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From: Roseville CA
Originally posted by Dan_03Lightning
Beautiful, and yes the '03 - '04's shall we say have a little more spring to increase payload numbers.................... unfortunately when you install the 3" drop shackles you add increased pressure to the rear suspension and you must relocate the anti-sway bar arms on the frame rails to relax the suspension...... believe me "been there done that" - it is really easy just measure up 2.5 inches on the frame railes drill new holes and reposition the arms, yes it actually works.
D-Day
Beautiful, and yes the '03 - '04's shall we say have a little more spring to increase payload numbers.................... unfortunately when you install the 3" drop shackles you add increased pressure to the rear suspension and you must relocate the anti-sway bar arms on the frame rails to relax the suspension...... believe me "been there done that" - it is really easy just measure up 2.5 inches on the frame railes drill new holes and reposition the arms, yes it actually works.
D-Day
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Joined: Dec 2000
Posts: 724
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From: EL Sobrante, CA ,
aside from needing to adjust the sway bar arms to get it relocated correctly there is no increased presure on the rear suspension, my truck has been lowered 4'' in the rear and I still need to adjust the rear sway bar but its not a big deal.Marty, its nothing to worry about.
Larry.
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Joined: Feb 2004
Posts: 657
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From: Abilene, TX
looks good man, I think dropin the L will be my next mod. Has anyone used the Ford Motorsport drop kit its has front springs 1.5" rear shackles 2". Just curious how that one is, will a 2'' in drop in the rear even really do anything, that doesn't seem like that much
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Joined: May 2003
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From: Los Angeles
Originally posted by SLVRLTNG
good instructions, but you don't really need to remove the rear wheels.......JR
good instructions, but you don't really need to remove the rear wheels.......JR
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Senior Member
Joined: Dec 2002
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From: Eastern TN
Originally posted by SLVRLTNG
good instructions, but you don't really need to remove the rear wheels.......JR
good instructions, but you don't really need to remove the rear wheels.......JR
