1981 3/4 ton 2wd GMC chassis question

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81gmc

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1981
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454
Hey Guys can someone fill me in on 3/4 ton chassis vs 1/2 ton and if front end parts are interchangeable I want make it 1/2 ton or know if I can put 1/2 ton suspension up front ?
 

AuroraGirl

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the 2wd chassis is beefier for a 3/4 ton such as a larger spindle, bigger hub and lug, larger brakes.(I mean, if im wrong someone point it out but I am pretty sure?). springs would be different. no idea about control arms tho. it probably isnt every part
Are you trying to make a 3/4 ton truck into 1/2 ton capability or you just want the ride quality.. maybe wheel/tire options..?
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here is a pic of a 3/4 ton 2wd but its not all that helpful, but something maybe?
 

ali_c20

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My c20 is a rough ride but when you haul stuff with it it improves a lot. If you are looking for better ride quality change the springs and shocks.
Welcome from Austria and we want pics btw.
 

81gmc

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Thanks byes just looking make it 1/2 ton ride and 5 bolt pattern wheels
 

ali_c20

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You would need to change everything ( A arms are different, they have bronze bushings and different ball joints.) to put on 5 bolt pattern wheels. Also calipers and maybe the master brake cylinder too as it is a 1.25 bore for the bigger c20 calipers or you buy a hd c10 rotor than the calipers and mc don't have to go. And the rear axlehas to go too.
 

81gmc

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That don’t bother me so I would need control arm with rubber bushings and spindles and brakes not big deal thx
 

AuroraGirl

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That don’t bother me so I would need control arm with rubber bushings and spindles and brakes not big deal thx
it would honestly be easier to find a half ton truck... the amount to change everything over to 5x5.5 and put lower rated springs on the rear(if you have a ff you have to do a lot of work to get 5x5.5 but if you have a semi float its not so hard). are you sure you wouldnt rather just trade or sell your truck? Honestly if you are committed to this truck, maybe buying a c10 to at least have base-parts, you could switcheroo them around
 

Bextreme04

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Honestly the difficult part is changing the lug pattern. If you just want a softer ride, changing the springs is just that easy, change to 1/2 ton springs and move on. They are interchangeable, just softer.
 

rick1956

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Here in Washington you've got to pay more licensing based on the tonnage... the creative folks around here will buy a C10 and transfer everything C20 spring/axle related over to the C10 for hauling capability. I've only seen one that swapped the other way, and it was for sale on Craigy's List.
 

Rickf

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Can you use 1/2 ton springs and re-drill the hubs for 5 lug wheels?
 

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