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Old 07-14-2008, 01:57 AM   #1
Croney103
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Question 1/2 and 1 tonnne leaf springs
How many Leaves are in 1/2 and 1 Tonne 73-87 C20 Pickup rear leaf springs? I want to lower my GVM (Gross Vehicle Mass) rating on my 1978 C20 as its now 3720 KG to under 3500 KG. An engineer told me I can do this by taking leaves out of the rear springs and I wondering how many would be enough, probaly a fair few as the rear suspension is insanely rock hard....
It needs to be fully loaded to actually spring
THere are 9 Leaves on it right now including the top one connected to the shackles and the bottom 3 aren't riveted on and will easily come out and then I'll just need shorter U-bolts.
I Need to to now if this is enough to lower it as is going to cost me like $700 to re-rate it and don't want to go back to the engineer again.
P.s Can anyone tell me the GVMs of the 1/2 and 1 tonne versions.
Thanks
Michael
Holden built 1978 Chevy C20
292, Sm465, 14 bolt, 31s, LPG.
2 Tonnes Of Fun...
Soon to be 350'ed, Lifted 4", 33-35s, and smashing through your living room wall....
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Old 07-14-2008, 03:13 AM   #2
GreaseDog
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Re: 1/2 and 1 tonnne leaf springs
IIRC 1/2 ton springs are 5 leaf. so if you were to go in and remove every other leaf, you should end up with something close. you say the bottom 3 arent riveted in? none of them should be riveted in, there is a bolt that runs through the center of all of them.
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Old 07-14-2008, 07:18 AM   #3
Croney103
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Re: 1/2 and 1 tonnne leaf springs
Thanks man
Holden built 1978 Chevy C20
292, Sm465, 14 bolt, 31s, LPG.
2 Tonnes Of Fun...
Soon to be 350'ed, Lifted 4", 33-35s, and smashing through your living room wall....
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Old 07-14-2008, 12:43 PM   #4
Ivan D.
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Re: 1/2 and 1 tonnne leaf springs
Croney, GD is right on - 5 leafs for a regular 1/2-ton truck, 7 for the so-called "heavy half" (which is a 1/2-ton frame with a 3/4-ton suspension). Also I second the suggestion of removing every other leaf, so that would be #2, 4, 6 and 8, no matter if you count them up-down or down-up.
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Old 07-14-2008, 06:25 PM   #5
Croney103
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Re: 1/2 and 1 tonnne leaf springs
thanks guys. Will do.
Holden built 1978 Chevy C20
292, Sm465, 14 bolt, 31s, LPG.
2 Tonnes Of Fun...
Soon to be 350'ed, Lifted 4", 33-35s, and smashing through your living room wall....
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Old 07-14-2008, 09:47 PM   #6
thebigcheez
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Re: 1/2 and 1 tonnne leaf springs
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