What trucks are classified as "Heavy Duty"?
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> I see the new 3/4 ton and 1 ton trucks are called heavy duty. Does this
> apply to older trucks as well?
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Basically, it's a marketing ploy. GM has two different 3/4 ton trucks... one with 6 lug studs, the other with 8 lug studs. The 6 lug truck is rated to 7,200 GVWR while the 8 lug truck is rated to 8,500 GVWR.
Same with the one ton trucks... one is rated up to 10,000 GVWR (the plain one ton truck) and other above that rating based on how it was built.