Just completed installing gas lift struts inside my stock lift gate supports (per Cooney's '06 post, locatable by searching NAPA part 819-5565 in this forum).
Cooney did his homework, and it works perfectly. Only have a few things to add:
Before you remove your chrome supports from the vehicle, make a note of how much they are compressed when the gate is closed. On mine, the top of the chrome locking nut just touches the bottom of the phillips head that is the set screw for the chrome upper bracket plug of the support.
Remove the supports with brackets as complete units, remove the set srews and unscrew the chrome cap and plug from each end. DO NOT mix and match your end pieces! (The set screw holes were drilled after assembly, apparently, and end pieces are dedicated!) Best to do one support modification completely before doing the other one. Remove the spring and the white nylon spacer (might need a gun cleaning rod to push the spacer out). Save the springs and spacers in case you want to return to manual labor toward your lift gate someday.
I left the end pieces on the NAPA 819-5565 gas strut, but modified them in order to have a "footing" on each end of the strut, instead of just the bare threaded end of the strut bearing on the inside (chrome cap and plug) of the stock support.
I sawed the tips of the plastic strut end pieces off, (about in half) and then ground them down flat so that they were only barely longer than the brass threaded grommet inside of each. This got me to the ideal length that Cooney spent so much time researching (to the chagrin of his local NAPA dealer). Then I ground the exterior of the plastic tips to a round shape that slides within the smaller diameter chrome tube of the stock supports. (You can use your original white nylon interior spacers
-removed with the spring- to guage the maximum diameter they can be. A bit smaller doesn't hurt.)
Your plastic end pieces of the gas strut now look like little black "Dots" candies with a threaded grommet inside them. This gives you a bearing pad at each end when the strut is inside the stock chrome lift gate support. Maybe this isn't necessary (ask Cooney how his are holding out), but I thought it was a better arrangement.
When you put the strut with pads inside the chrome support and screw in the cap and plug (prior to installation in the vehicle), the strut will rattle around a bit. This is of no consequence, however, since when installed in the vehicle and the gate is closed, the strut is under pressure, and when the gate opens itself, the weight of the gate still exerts pressure on the strut. (In other words, the strut no longer will be rattling around in there in either case.)
Trust Cooney's research on length: I thought that by leaving more on each end of those plastic tips, I might gain that extra half-inch of lift he talked about gaining with spacers. I found out that leaving hardly any more length on each end of the strut did not allow the gate to close. (So I installed, removed, ground more, installed again, etc., etc., only to find that Cooney was right.)
As Cooney noted, to get the highest lift possible on the gate, 1/2" spacers should be installed under the chrome upper brackets where they attach to the gate. I did not do this, since I'm kind of a tall guy, and I still can hit my head on the t-handle even with the gate at its highest. You can still get this extra half-inch by manually lifting the gate and locking the turn knobs, since these are not disabled in the process of strut installation.
The door now opens effortlessly, and without the spacers mentioned it rests perfectly at 90 degrees to the hard top. The heart of the improvement (the strut) is completely invisible, retaining the stock appearance of the chrome supports in their entirety.
Best "convenience" modification I've made to my '71 FJ40, by far. Thanks Cooney!!
Cooney did his homework, and it works perfectly. Only have a few things to add:
Before you remove your chrome supports from the vehicle, make a note of how much they are compressed when the gate is closed. On mine, the top of the chrome locking nut just touches the bottom of the phillips head that is the set screw for the chrome upper bracket plug of the support.
Remove the supports with brackets as complete units, remove the set srews and unscrew the chrome cap and plug from each end. DO NOT mix and match your end pieces! (The set screw holes were drilled after assembly, apparently, and end pieces are dedicated!) Best to do one support modification completely before doing the other one. Remove the spring and the white nylon spacer (might need a gun cleaning rod to push the spacer out). Save the springs and spacers in case you want to return to manual labor toward your lift gate someday.
I left the end pieces on the NAPA 819-5565 gas strut, but modified them in order to have a "footing" on each end of the strut, instead of just the bare threaded end of the strut bearing on the inside (chrome cap and plug) of the stock support.
I sawed the tips of the plastic strut end pieces off, (about in half) and then ground them down flat so that they were only barely longer than the brass threaded grommet inside of each. This got me to the ideal length that Cooney spent so much time researching (to the chagrin of his local NAPA dealer). Then I ground the exterior of the plastic tips to a round shape that slides within the smaller diameter chrome tube of the stock supports. (You can use your original white nylon interior spacers
-removed with the spring- to guage the maximum diameter they can be. A bit smaller doesn't hurt.)
Your plastic end pieces of the gas strut now look like little black "Dots" candies with a threaded grommet inside them. This gives you a bearing pad at each end when the strut is inside the stock chrome lift gate support. Maybe this isn't necessary (ask Cooney how his are holding out), but I thought it was a better arrangement.
When you put the strut with pads inside the chrome support and screw in the cap and plug (prior to installation in the vehicle), the strut will rattle around a bit. This is of no consequence, however, since when installed in the vehicle and the gate is closed, the strut is under pressure, and when the gate opens itself, the weight of the gate still exerts pressure on the strut. (In other words, the strut no longer will be rattling around in there in either case.)
Trust Cooney's research on length: I thought that by leaving more on each end of those plastic tips, I might gain that extra half-inch of lift he talked about gaining with spacers. I found out that leaving hardly any more length on each end of the strut did not allow the gate to close. (So I installed, removed, ground more, installed again, etc., etc., only to find that Cooney was right.)

As Cooney noted, to get the highest lift possible on the gate, 1/2" spacers should be installed under the chrome upper brackets where they attach to the gate. I did not do this, since I'm kind of a tall guy, and I still can hit my head on the t-handle even with the gate at its highest. You can still get this extra half-inch by manually lifting the gate and locking the turn knobs, since these are not disabled in the process of strut installation.
The door now opens effortlessly, and without the spacers mentioned it rests perfectly at 90 degrees to the hard top. The heart of the improvement (the strut) is completely invisible, retaining the stock appearance of the chrome supports in their entirety.
Best "convenience" modification I've made to my '71 FJ40, by far. Thanks Cooney!!
