rear shock tech

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Jul 24, 2007 | 12:58 PM

tastyklair

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From: Eastern Pa

rear shock tech

I need the measurement between the top and bottom mounts for the rear shocks on my 79 150 4x4. I replaced the springs but when reinstalling the rear shocks I had to push the bed down to get them remounted as it appeared either the shocks had been wrong and were too short or the springs lifted it more than stock height. Where should the shock be in it's travel when at rest?

Jul 24, 2007 | 01:16 PM

NOCO77

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From: Northern Colorado

Preferably near mid-point of the shock's total travel.

Jul 24, 2007 | 01:44 PM

75F350

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Typically springs will allow a greater amount of extension and not quite compress as much, but is only a big deal on very high flex vehicles where the shocks stroke can be a limiting factor.
In your case, if you have the shock fully extended, and you have to compress the spring to get it to fit, then shock is way too short, and you will suffer from a terrible ride, and ruin the shock. The shock is fully extended because it is too short and is currently topped out, or has reached the end of the stroke. Correct it, or you will suffer some damage. Shock mounts can be compromised, and the shock will be destroyed.

Jul 24, 2007 | 06:15 PM

tastyklair

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From: Eastern Pa

The shocks were in fact kaput, and the ride did stink. I still need to know what the distance should be between the mounts. I am refabbing the upper mounts as they were going away and could make them to be the correct distance if I knew what that was. I want to get it back together soon as I can so I can paint before it's too cold out. It's currently in frame off condition.

Jul 24, 2007 | 06:28 PM

petes79f150

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From: Kiefer, Northeastern Okla

You can actually put the mounts at just about any distance. Rancho, Koni, Afco and others offer shocks in varying lengths and rates for fabbed suspension and chassis systems. I like the Afco's. Kinda pricey, but worth it IMO. Just call the tech line at any shock maker, they'll hook you up.

Pete

Jul 24, 2007 | 11:09 PM

75F350

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If the springs have been changed, and the a bigger spring has been used, will mean that the stock shock will still be too short. Getting a measurement from someone with a different spring that yours will have a different length shock that yours. You simply need to mount the brackets on the frame, and measure the distance between the top mount, and the bottom mount, (this is the static heigth of the vehicle) while on level ground, and take these measurements to the parts store where you will be buying new shocks.