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Old 07-26-2020, 08:59 PM   #1
BigTruckDriver
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Lowering rear 1.5"?

What are my options with the least amount of modifications? Not looking to cut bed support for a 2" shackle.
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Old 07-26-2020, 09:25 PM   #2
sweetk30
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Re: Lowering rear 1.5"?

drop springs or drop hanger for the front spring eye location.

i did mine with the drop hanger and shackle to get it dialed in . i just moved my hanger up and re-drilled the holes and used 7/16 bolts with stover / crimp lock nuts . then the rear i did have to notch the crossmember on the box for the shackle .

but mine i went down 2.5" front and rear . so if you did just hanger in the rear at the front of the leaf spring you will prob be fine i think . just be sure to check pinion angle .
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Old 07-27-2020, 09:24 AM   #3
bigblock73
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Re: Lowering rear 1.5"?

If you have the longer HD springs, a drop shackle will clear the bed support. The shorter LD springs are the ones that will interfere with a drop shackle.
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Old 07-27-2020, 12:25 PM   #4
sweetk30
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Re: Lowering rear 1.5"?

std issue is 52" eye to eye .

hd is the 56" eye to eye . and its 4" longer on the back side only .

and the shackle hanger bracket is back 4" in the extra frame holes . most i have seen have the extra frame holes already there .
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77-k30lb BIG truck build .
87-k30lb budget beater build .
85-k30lb the plow machine build .
85-c10sb summer fun toy .
-----------------------------
HOLLEY SNIPER efi = worst case of p.i.t.a i ever had .

EDELBROCK pro flo 4 = best deal going so far . love my setup works great.
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Old 07-27-2020, 01:57 PM   #5
bigblock73
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Re: Lowering rear 1.5"?

Quote:
Originally Posted by sweetk30 View Post
std issue is 52" eye to eye .

hd is the 56" eye to eye . and its 4" longer on the back side only .

and the shackle hanger bracket is back 4" in the extra frame holes . most i have seen have the extra frame holes already there .
You are correct.
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Old 07-27-2020, 09:40 PM   #6
BigTruckDriver
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Re: Lowering rear 1.5"?

Looks like drop leaf springs are going to be my best bet. I am also looking to pull a trailer . Any reputable place to purchase from?
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Old 07-27-2020, 10:16 PM   #7
MikeB
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Re: Lowering rear 1.5"?

Problem with just doing raised hangers or longer shackles (and not both) is the pinion angle will change and you will need angled spring shims to raise or lower the differential nose. if I had a do-over, I'd go with lowered springs.
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