Author Topic: lowering a 78 GMC Sub cheaply  (Read 6390 times)

Offline Hook

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lowering a 78 GMC Sub cheaply
« on: October 12, 2007, 07:18:44 pm »
I  want to lower my 2 wheel drive 78 burb. It has a 454 and is 2500 series w/ 8 lug wheels. Looking for the most economical way to do this. I haven't owned this long and actually haven't even looked at the suspesion in detail. Cut front springs or use SB chevy springs? Blocks work in the rear or is it SOA? I have alot of experience doing all my own mechanical work so tools are not a problem. This is a 3rd vehicle and only used to tow a trailer occassionally and haul our 3 large dogs to the beach, etc.
78 Suburban 2500 454/th400- SOLD!!!!!!!
Looking for a new 73-87 Chevy
70 Camaro 350/th400
89 Mustang 5.0/AOD

Offline FlatBlack77

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Re: lowering a 78 GMC Sub cheaply
« Reply #1 on: October 12, 2007, 09:03:25 pm »
nice Sub'. at first glance i thought you had a satellite dish on the top because of the basketball hoop.

you could cut the coils up front. I think one whole coil will lower it two inches. and you could take some leafs off the back but I don't know how well it would work for towing anything.
"When you are a hammer, everything looks like a nail"
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Offline Dragon

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Re: lowering a 78 GMC Sub cheaply
« Reply #2 on: October 17, 2007, 12:53:55 am »
Drop Blocks for Rear(Says Lift, but are Universal between the two.).
http://www.performancecenter.com/product/Lowering+Kits+%26+Handling/Blocks/0/4/0/GMC/1978/Suburban+3%7E4+Ton/Vehicle+Specific+Blocks
As for the Front Springs, your Stock Springs would have sagged enough over the years, so I would start out removing 1/4-1 whole coil(Only do a little at a time). 

SBC Front Coils won't be able to properly handle the weight of the 454, and you would get an additional un-wanted sag to them.
Dragon
08 Magnum-New Toy
96 Caprice 9C1-Who Knows
96 GMC ECLWB & 92 Chevy ECLWB
77 GMC K25 HS-Gone but Not Forgotten

Offline Captkaos

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Re: lowering a 78 GMC Sub cheaply
« Reply #3 on: October 17, 2007, 09:07:36 am »
Block on the rear will LIFT a factory Suburban.  Factory setup is SOA.

The big question is How much you want it lowered?

Options for the rear is shackles and hangers or a flip kit.
Options for the front is drop springs (or cutting 1/2 coil off) OR convert it to 1/2T setup and use 1/2T HD spindles.

SBC springs will hold a 454 ( I used them for 10 years), there is no difference in aftermarket springs concerning BBC vs SBC for drop springs.  Using SBC springs will drop it about 1".

Offline VileZambonie

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Re: lowering a 78 GMC Sub cheaply
« Reply #4 on: October 17, 2007, 12:29:28 pm »
I would go drop spindles in the front and shackles in the back or don't even bother. You'll ruin your ride quality and towing capacity cutting/eliminating springs
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Offline Dragon

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Re: lowering a 78 GMC Sub cheaply
« Reply #5 on: October 18, 2007, 11:47:35 pm »
Block on the rear will LIFT a factory Suburban.  Factory setup is SOA.

The big question is How much you want it lowered?

Options for the rear is shackles and hangers or a flip kit.
Options for the front is drop springs (or cutting 1/2 coil off) OR convert it to 1/2T setup and use 1/2T HD spindles.

SBC springs will hold a 454 ( I used them for 10 years), there is no difference in aftermarket springs concerning BBC vs SBC for drop springs.  Using SBC springs will drop it about 1".
You're right, Sorry I was thinking that the rear was already over the springs like a car.
Dragon
08 Magnum-New Toy
96 Caprice 9C1-Who Knows
96 GMC ECLWB & 92 Chevy ECLWB
77 GMC K25 HS-Gone but Not Forgotten

Offline Long Roof

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Re: lowering a 78 GMC Sub cheaply
« Reply #6 on: October 19, 2007, 01:46:02 am »
BrothersTrucks.com has a 3/4 ton drop spindle.

Offline Hook

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Re: lowering a 78 GMC Sub cheaply
« Reply #7 on: October 19, 2007, 08:34:38 am »
Thanks guys. I will proably go with the dropped spindles since I only want to do it once. I want a drop something in the range of 3" in the front and probably 2-2.5 in the rear. Once I get moved and have a garage to work in. Need it to tow my Camaro to Vegas.
78 Suburban 2500 454/th400- SOLD!!!!!!!
Looking for a new 73-87 Chevy
70 Camaro 350/th400
89 Mustang 5.0/AOD