How do ya drop the rear of a C20 with leafs 2"? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

MrC1 · 09-17-2005, 12:43 AM

Sorry for the barrage of questions!

I know there's lots of threads about this, but I couldn't find this specific answer.

I've got a '72 C20 with leaf rear suspension (HD option?) Anyway, I want to leave the ride height stock for now, 'cept I'd like to drop the rear 2" to level it out. How's this done? Are there 2" longer shackles available? If so, where?

It appears that 2" longer shackles might not quite fit under the bed, but I'm not sure. It's a fleetside metal bed, BTW.

69 Short Fleet · 09-17-2005, 01:42 AM

Not sure on a C/20. I just got Early Classics catalog today and they only offer leafsprings (with drop) for C/10's. I don't remember seeing anything for the 3/4 tons from any vendors. Doug

tomatocity · 09-17-2005, 01:56 AM

Check the catalogs or contact one of the Board vendors like GMCPauls or any of the others. They are all good companies with good employees.

How wide are your leaf springs? What is the length (bushing to bushing) of your leaf springs. My leafs are 2.25" wide adn approx. 51+" long (bushing center to bushing center).

llegos · 09-17-2005, 02:45 AM

take out a leaf?

chickenwing · 09-17-2005, 05:42 PM

I'm lookin at raising the front. Still playing with these http://www.classicperform.com/Store/...k/6372SHKR.htm

Tomatocity and I have talked about it before. Spring dimensions will be important to make sure the shackle will fit. Talk to tech support of whatever company you choose.

69 longhorn · 09-17-2005, 06:11 PM

For such a minor drop,possibly rearching the springs may be the best route.you will still have the load capacity, & no issues with longer shackles/box floor clearance. best of luck, 69L

tomatocity · 09-23-2005, 01:21 AM

Rich these are drop shackles and they would lower your truck. I think we should slam your truck and leave the same wheels and tires on it

Quote:

Originally Posted by chickenwing

I'm lookin at raising the front. Still playing with these http://www.classicperform.com/Store/...k/6372SHKR.htm

Tomatocity and I have talked about it before. Spring dimensions will be important to make sure the shackle will fit. Talk to tech support of whatever company you choose.

72MARIO · 09-17-2005, 07:00 PM

That would be "dearching" Longhorn

Any local spring shop will pull the pack and flatten them out 2" usually under $100.00.

chickenwing · 09-18-2005, 11:42 AM

Didn't know that was a common thing. Thought it was a "lost art". I love this place. Thanks for the thread and info.

MrC1 · 09-20-2005, 10:37 PM

Thanks for the info guys. I was hoping to hear that a longer shackle was available (or somethin gsimilar), but maybe it's not. I've searched all over, but haven't found anything.

I may end up rearching the springs, but I'd prefer not to.

masterbeavis · 09-21-2005, 12:27 AM

Dumb question, but is you axle spring under or spring over? Not knowing much about somethings maes me have to ask. If it was sprung under, you could put a block in there lowering it more??!?!

1969 GMC · 09-21-2005, 02:00 AM

Quote:

Originally Posted by masterbeavis

Dumb question, but is you axle spring under or spring over? Not knowing much about somethings maes me have to ask. If it was sprung under, you could put a block in there lowering it more??!?!

They're sprungover.

My personal suggestion is, a bed full of bricks.

XXL · 09-21-2005, 02:05 AM

Quote:

Originally Posted by MrC1

I've got a '72 C20 with leaf rear suspension (HD option?) Anyway, I want to leave the ride height stock for now, 'cept I'd like to drop the rear 2" to level it out. How's this done? Are there 2" longer shackles available? If so, where?

Longer shackles will take you the wrong direction.

Ray's Fort Worth Champion Spring. Have them dearched to whatever ride height you want. You'll maintain the mechanical integrity of the spring pack (load capacity, spring rate, etc.), which will be altered substantially if you start pulling leaves out of the spring pack.

MrC1 · 09-21-2005, 08:44 PM

Quote:

Originally Posted by XXL

Longer shackles will take you the wrong direction.

Actually, they hang DOWN to the springs, so longer ones WILL work.

XXL · 09-21-2005, 10:52 PM

Quote:

Originally Posted by MrC1

Actually, they hang DOWN to the springs, so longer ones WILL work.

I guess I'm missing something. If the shackles connect on top at the frame and on the bottom at the spring, making them longer lowers the spring mount, which is the same as raising everything above the spring mount. It's been a while since I've looked at a leaf version of thse trucks, but I believe the spring eye is on the low end of the shackle.

69 longhorn · 09-22-2005, 09:21 AM

Quote:

Originally Posted by XXL

I guess I'm missing something. If the shackles connect on top at the frame and on the bottom at the spring, making them longer lowers the spring mount, which is the same as raising everything above the spring mount. It's been a while since I've looked at a leaf version of thse trucks, but I believe the spring eye is on the low end of the shackle.

Your sketches show how most of the mid 60's leaf sprung muscle cars were set up. longer shackles did lift them. the trucks are setup differently tho......the spring is above the frame perch, & the shackle drops from the spring eye , down to the perch. longer shackles do lower a truck, but how far you can go without hitting a cross rail , or the bed floor doesnt work to be much more than 1" or so(depending on wood, or steel floor). If you can get enough drop with a shackle.....I would sure go that way, as it would be by far the easiest route

L

MrC1 · 09-22-2005, 08:04 PM

Where can I get longer shackles though? Anybody make them?

XXL · 09-23-2005, 10:53 AM

Quote:

Originally Posted by 69 longhorn

the spring is above the frame perch, & the shackle drops from the spring eye , down to the perch.

Aha! I thought I was missing some fact... thanks for the clarification.

Maximum Overdrive · 09-21-2005, 12:07 PM

Let the air out of the rear tires until you achieve the 2 inches.

Not sure how yours is set up but mine has overloads on it and by simply taking out the overload springs and the spacer and then using new u bolts I could acheive 2-3 inch drop on the rear of my truck.

MrC1 · 09-21-2005, 08:46 PM

Quote:

Originally Posted by Maximum Overdrive

Not sure how yours is set up but mine has overloads on it and by simply taking out the overload springs and the spacer and then using new u bolts I could acheive 2-3 inch drop on the rear of my truck.

I've got the overload springs too, but that's only about 1/2"-3/4" of thickness. I'm not sure what spacer you're referring to.

69moneypit · 09-21-2005, 01:40 PM

I took my truck to a spring shop and they removed the leaves and individually de arched each one. I do not know how much it changed the amount of a load I can haul.

tomatocity · 09-21-2005, 01:48 PM

Quote:

Originally Posted by 69moneypit

I took my truck to a spring shop and they removed the leaves and individually de arched each one. I do not know how much it changed the amount of a load I can haul.

Probably less expensive if you removed them yourself and took them into the shop. May I ask what the cost was?

chickenwing · 09-23-2005, 08:34 AM

What's next? Dingo balls?

09-17-2005, 12:43 AM	#1
MrC1 Dork For Days Join Date: Aug 2005 Location: Dallas Posts: 407	How do ya drop the rear of a C20 with leafs 2"? Sorry for the barrage of questions! I know there's lots of threads about this, but I couldn't find this specific answer. I've got a '72 C20 with leaf rear suspension (HD option?) Anyway, I want to leave the ride height stock for now, 'cept I'd like to drop the rear 2" to level it out. How's this done? Are there 2" longer shackles available? If so, where? It appears that 2" longer shackles might not quite fit under the bed, but I'm not sure. It's a fleetside metal bed, BTW.

09-17-2005, 01:56 AM	#3
tomatocity Registered User Join Date: Jun 2005 Location: Sacramento CA Posts: 1,255	Check the catalogs or contact one of the Board vendors like GMCPauls or any of the others. They are all good companies with good employees. How wide are your leaf springs? What is the length (bushing to bushing) of your leaf springs. My leafs are 2.25" wide adn approx. 51+" long (bushing center to bushing center). __________________ Got bored, sold everthing. Got bored, looking for a 1960-66 C-10. Want to build my last truck.

09-17-2005, 02:45 AM	#4
llegos Registered User Join Date: Aug 2005 Location: pleasanton, CA Posts: 570	take out a leaf? __________________ -Steve

09-17-2005, 06:11 PM	#6
69 longhorn Registered User Join Date: Aug 2001 Location: rock island,il,usa Posts: 5,382	For such a minor drop,possibly rearching the springs may be the best route.you will still have the load capacity, & no issues with longer shackles/box floor clearance. best of luck, 69L __________________ http://community.webshots.com/user/hotrodhorn

09-17-2005, 07:00 PM	#8
72MARIO Registered User Join Date: Nov 2000 Location: Huntsville Ontario Canada Posts: 4,052	That would be "dearching" Longhorn Any local spring shop will pull the pack and flatten them out 2" usually under $100.00. __________________ 1968 Suburban numbers matching all original truck now equipped with 6.0/4L80 on Accuair http://67-72chevytrucks.com/vboard/s...d.php?t=625017 1967 C/20 6.0/4L80 Roofing Truck 1990 V2500 Suburban "Plow Truck" 2005 TAHOE DD

09-17-2005, 01:42 AM	#2
69 Short Fleet Registered User Join Date: Nov 2002 Location: Kelowna B.C. Canada Posts: 1,086	Not sure on a C/20. I just got Early Classics catalog today and they only offer leafsprings (with drop) for C/10's. I don't remember seeing anything for the 3/4 tons from any vendors. Doug

09-17-2005, 05:42 PM	#5
chickenwing Lovin' Life in Miss.! Join Date: Mar 2004 Location: Puckett, Mississippi Posts: 1,937	I'm lookin at raising the front. Still playing with these http://www.classicperform.com/Store/...k/6372SHKR.htm Tomatocity and I have talked about it before. Spring dimensions will be important to make sure the shackle will fit. Talk to tech support of whatever company you choose.

09-18-2005, 11:42 AM	#9
chickenwing Lovin' Life in Miss.! Join Date: Mar 2004 Location: Puckett, Mississippi Posts: 1,937	Didn't know that was a common thing. Thought it was a "lost art". I love this place. Thanks for the thread and info.

09-20-2005, 10:37 PM	#10
MrC1 Dork For Days Join Date: Aug 2005 Location: Dallas Posts: 407	Thanks for the info! Thanks for the info guys. I was hoping to hear that a longer shackle was available (or somethin gsimilar), but maybe it's not. I've searched all over, but haven't found anything. I may end up rearching the springs, but I'd prefer not to.

09-21-2005, 12:27 AM	#11
masterbeavis Having issues Join Date: Jul 2005 Location: Eldorado Ca, an hour east of sacramento Posts: 696	Dumb question, but is you axle spring under or spring over? Not knowing much about somethings maes me have to ask. If it was sprung under, you could put a block in there lowering it more??!?! __________________ Quando Omni Flunkus Moritati. The Man's Prayer: "I'm a man, but I can change, if I have to, I guess."

09-22-2005, 08:04 PM	#17
MrC1 Dork For Days Join Date: Aug 2005 Location: Dallas Posts: 407	Where though? Where can I get longer shackles though? Anybody make them?

09-21-2005, 12:07 PM	#19
Maximum Overdrive December 21, 2012 Join Date: Apr 2000 Location: Black Eagle, Montana Posts: 1,634	Let the air out of the rear tires until you achieve the 2 inches. Not sure how yours is set up but mine has overloads on it and by simply taking out the overload springs and the spacer and then using new u bolts I could acheive 2-3 inch drop on the rear of my truck. __________________ *"!Ama Sua, Ama Kjella, Ama Lllulla!"*

09-21-2005, 01:40 PM	#21
69moneypit Divorced .....WITH KIDS Join Date: Dec 2003 Location: mississippi Posts: 619	I took my truck to a spring shop and they removed the leaves and individually de arched each one. I do not know how much it changed the amount of a load I can haul. __________________ 1969 GMC SWB 1975 Chevy Malibu 80k 1963 Ford Galaxie 63k (inherited) 2005 Nissan Armada (wife's idea)

09-23-2005, 08:34 AM	#23
chickenwing Lovin' Life in Miss.! Join Date: Mar 2004 Location: Puckett, Mississippi Posts: 1,937	What's next? Dingo balls? Last edited by chickenwing; 09-23-2005 at 08:34 AM.



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