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Old 12-11-2019, 04:06 PM   #1
1981_c10
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Static Drop

Friends, I am going to installing a 2.5/4 inch drop on my 81 C10 over the Holidays and would love some pro tips before starting. here are the plans and parts i currently have:

Front:
2.5 drop spindles
stock replacement coil springs
New ball joints
Stock replacement shocks (didnt think i needed lowering shocks due to spindle)
Sway bar
Should i replace the bushings in the control arms? (i have not purchased new ones yet)

Rear:
2 in hangers
2 inch shackles
Drop shocks or stock? (havent purchased yet)
Should i replace the bushings in the leaf springs? (havent purchased yet)

This will be my first time doing this so any info is helpful!

Thanks!
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Old 12-11-2019, 07:49 PM   #2
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Re: Static Drop

I am a fan of refreshing and making things 'new' whenever I get into them. That being said, I would definitely replace what was needed while you are in there.
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Old 12-13-2019, 10:37 AM   #3
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Re: Static Drop

Bushings are likely toast if it's been used & not a yard queen (the last Square trucks built are 40yrs old now). inspect them & plan accordingly. Your plan for the front seems good & you're correct the shock travel won't change w/the spindle swap.

For the rear, same rules apply for the leaf bushings. I would opt for relocating the lower shock mounting point w/shock extension brackets to get a better angle on the shocks & to allow using stock spec replacement shocks vs. 'drop' shocks.

When you get it aligned, the 'book' will call for +.5 Camber. Request 0 (zero) to -.5 Camber & as much Caster as they can dial in w/that new Camber set-point. The lower center of gravity & updated camber spec will be an improvement.

Check the other steering parts while you're in there. The tie-rod ends, Idler, & Pitman arms need to be in good shape as well. Summit Racing offers the Moog product line & they're usually 50% less than your local parts place on the price.
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Old 12-13-2019, 11:02 AM   #4
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Re: Static Drop

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Originally Posted by SCOTI View Post
Bushings are likely toast if it's been used & not a yard queen (the last Square trucks built are 40yrs old now). inspect them & plan accordingly. Your plan for the front seems good & you're correct the shock travel won't change w/the spindle swap.

For the rear, same rules apply for the leaf bushings. I would opt for relocating the lower shock mounting point w/shock extension brackets to get a better angle on the shocks & to allow using stock spec replacement shocks vs. 'drop' shocks.

When you get it aligned, the 'book' will call for +.5 Camber. Request 0 (zero) to -.5 Camber & as much Caster as they can dial in w/that new Camber set-point. The lower center of gravity & updated camber spec will be an improvement.

Check the other steering parts while you're in there. The tie-rod ends, Idler, & Pitman arms need to be in good shape as well. Summit Racing offers the Moog product line & they're usually 50% less than your local parts place on the price.
Thanks for the helpful info! Luckily my truck only has 120K miles on it so I will give it all a good look. Alignment tips are super helpful! Will keep everyone updated on my results.
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Old 01-02-2020, 04:22 PM   #5
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Re: Static Drop

See the attached pictures for the update. Almost finished...ran into every problem you could imagine from having to break my wheel locks off to couldnt get the new shock in because the gasket was big...now i am fighting bearing race. Once i finish those, i will do the sway bar and rear.
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Old 01-02-2020, 04:22 PM   #6
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Re: Static Drop

Old shocks...
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Old 01-02-2020, 06:31 PM   #7
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Re: Static Drop

It's coming along well! I always run into issue, its kind of expected at this point.

I assume you have the 1" brakes? The spindles look different.
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Old 01-09-2020, 03:37 PM   #8
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Re: Static Drop

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Originally Posted by wixthedog View Post
It's coming along well! I always run into issue, its kind of expected at this point.

I assume you have the 1" brakes? The spindles look different.
Thank you! And yes you are correct in the 1 inch spindles. I honestly bought the spindles on CL for a really good deal like 5 years ago and didnt check if they were the correct ones...but my luck paid off this time!
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Old 01-22-2020, 10:07 PM   #9
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Smile Re: Static Drop

So how'd it end up coming out? I'm looking to do a static drop in the future and I'd like to see your results.
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Old 01-31-2020, 06:27 PM   #10
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Re: Static Drop

Front is done, minus the sway bar i need to install. Pretty happy with the front. Honestly, will probably end up cutting a coil off the springs i installed to try to lower the front one more inch.

Rear should be done in the next week or two. i will post updates.

The steering is way better with the truck lowered though. With that said, need and alignment lol
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Old 02-01-2020, 12:30 AM   #11
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Re: Static Drop

1/2 coil = 1” of drop.
That’s a rule I go by.
1 full coil will get you about 2” of drop.
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Old 02-11-2020, 12:15 AM   #12
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Re: Static Drop

How much net drop did you get on the front? I installed 2.5" spindles with new Moog coil springs (the softest they had), but ended up with a net drop of around 1.5". Turns out the new springs are the same extended height, but a little stiffer than the basic OE springs. Anyway, the truck has settled another 1/2" or so since then. I think my avatar picture is before the drop.
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Old 02-18-2020, 03:27 PM   #13
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Re: Static Drop

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How much net drop did you get on the front? I installed 2.5" spindles with new Moog coil springs (the softest they had), but ended up with a net drop of around 1.5". Turns out the new springs are the same extended height, but a little stiffer than the basic OE springs. Anyway, the truck has settled another 1/2" or so since then. I think my avatar picture is before the drop.
I ended with the same 1.5 net drop as you. That is why i want to eventually cut part of a coil off. Did you do hangers and shackles in the rear? Any advice?
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Old 02-18-2020, 03:27 PM   #14
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Re: Static Drop

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Originally Posted by lolife99 View Post
1/2 coil = 1” of drop.
That’s a rule I go by.
1 full coil will get you about 2” of drop.
That is good to know. Better to start small haha.
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Old 02-19-2020, 08:12 PM   #15
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Re: Static Drop

Wish I would have sen this sooner. I'm right up the road and have a small press for removing and replacing the bushings. I just did the rear springs and shackles this past weekend. Took about 20 minutes to r&r all 6.

Hoping to do the fronts this weekend.
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