The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 07-26-2020, 08:59 PM   #1
BigTruckDriver
Registered User
 
BigTruckDriver's Avatar
 
Join Date: Apr 2007
Location: Dallas
Posts: 156
Lowering rear 1.5"?

What are my options with the least amount of modifications? Not looking to cut bed support for a 2" shackle.
BigTruckDriver is offline   Reply With Quote
Old 07-26-2020, 09:25 PM   #2
sweetk30
Registered User
 
sweetk30's Avatar
 
Join Date: May 2012
Location: horseheads,ny rust belt
Posts: 2,794
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 .
__________________
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.
sweetk30 is offline   Reply With Quote
Old 07-27-2020, 09:24 AM   #3
bigblock73
yeller
 
bigblock73's Avatar
 
Join Date: Oct 2001
Location: Twin Cities
Posts: 13,826
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.
bigblock73 is offline   Reply With Quote
Old 07-27-2020, 12:25 PM   #4
sweetk30
Registered User
 
sweetk30's Avatar
 
Join Date: May 2012
Location: horseheads,ny rust belt
Posts: 2,794
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 .
__________________
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.
sweetk30 is offline   Reply With Quote
Old 07-27-2020, 01:57 PM   #5
bigblock73
yeller
 
bigblock73's Avatar
 
Join Date: Oct 2001
Location: Twin Cities
Posts: 13,826
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.
bigblock73 is offline   Reply With Quote
Old 07-27-2020, 09:40 PM   #6
BigTruckDriver
Registered User
 
BigTruckDriver's Avatar
 
Join Date: Apr 2007
Location: Dallas
Posts: 156
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?
BigTruckDriver is offline   Reply With Quote
Old 07-27-2020, 10:16 PM   #7
MikeB
Senior Member
 
MikeB's Avatar
 
Join Date: Jul 2000
Location: North Texas
Posts: 3,375
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.
__________________
Mike
1969 C10 LWB -- owned for 34 years. 350/TH350, 3.08 posi, 1st Gen Vintage Air, AAW wiring harness, 5-lug conversion, 1985 spindles and brakes.
1982 C10 SWB -- sold
1981 C10 Silverado LWB -- sold, but wish I still had it!
1969 C10 (not the current one) that I bought in the early 1980s. Paid $1200; sold for $1500 a few years later. Just a hint at the appreciation that was coming.
Retired as a factory automation products salesman.
Worked part-time over the years for an engine builder and a classic car repair shop.
Member here for 23 years! This is the very first car/truck Internet forum I joined. I still used a dial-up modem back then!
MikeB is offline   Reply With Quote
Old 07-30-2020, 12:56 PM   #8
Keith Seymore
Registered User
 
Keith Seymore's Avatar
 
Join Date: May 2009
Location: Motor City
Posts: 9,135
Re: Lowering rear 1.5"?

You could raise the production spring hangers on the frame rail.

http://67-72chevytrucks.com/vboard/s...d.php?t=509224

K
__________________
Chevrolet Flint Assembly
1979-1986
GM Full Size Truck Engineering
1986 - 2019
Intro from an Old Assembly Guy: http://67-72chevytrucks.com/vboard/s...d.php?t=342926
My Pontiac story: http://forums.maxperformanceinc.com/...d.php?t=560524
Chevelle intro: http://www.superchevy.com/features/s...hevy-chevelle/
Keith Seymore is offline   Reply With Quote
Old 08-04-2020, 01:54 PM   #9
72c20customcamper
Registered User
 
72c20customcamper's Avatar
 
Join Date: Jul 2018
Location: Catskill Mountains,NY
Posts: 8,053
Re: Lowering rear 1.5"?

I bought my lowering leafs from Western chassis. They are not to got on communication and took 12 business days to get the rears still waiting on the fronts UPS says Thursday. But the leafs I got look to be very nice and came from st Loius spring . I'd get a picture but right now were getting hammered with wind and rain

If I had known I would have ordered directly from them
http://www.saintlouisspring.com/
__________________
Mark
72 c20 custom camper Husky edition,
66 SS396 Chevelle 1964 Hawk, 63 Avanti,62 lark
1969 AMX ,
1968 c20 stepside ,85 K20
1977 Suburban sold
68 anniversary.

Last edited by 72c20customcamper; 08-04-2020 at 04:48 PM.
72c20customcamper is offline   Reply With Quote
Old 08-04-2020, 06:17 PM   #10
72c20customcamper
Registered User
 
72c20customcamper's Avatar
 
Join Date: Jul 2018
Location: Catskill Mountains,NY
Posts: 8,053
Re: Lowering rear 1.5"?

An hour ago we had 50 plus sustained winds and heavy rain . Now its calm and sunny . Pic of the newleafs old leafs are 8 new ones are 10 and American made
Attached Images
  
__________________
Mark
72 c20 custom camper Husky edition,
66 SS396 Chevelle 1964 Hawk, 63 Avanti,62 lark
1969 AMX ,
1968 c20 stepside ,85 K20
1977 Suburban sold
68 anniversary.
72c20customcamper is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 04:54 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com