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#1 |
Registered User
Join Date: Jul 2010
Location: PNW (Washington)
Posts: 75
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Need some help,
Trying to figure out the stock tire size of a 1972 gmc longbed 2wd sierra grande? We recently put some tires on, and have a speedometer problem, it's off by about 15 miles an hour. Still haven't replaced the speedo gear, but this truck has the original engine/trans still.. looking for stock factory tire size
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#2 |
Senior Member
Join Date: Jan 2003
Location: daytonabeach
Posts: 22,956
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Re: Need some help,
1/2 or 3/4ton?? you do realize theywere bias ply tires that came on these trucks?
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71c-10 350/2004r/4:11 lowered3/4 longbed/dead by hurricane MEANING OF DEATH::::: SOMEBODY ELSE GETS YOUR STUFF DONT BELIEVE EVERYTHING YOU THINK TAKE MY ADVISE;I DON'T USE IT ANYWAY |
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#3 |
Registered User
Join Date: Nov 2001
Location: Moneta, VA USA
Posts: 3,079
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Re: Need some help,
If it's a 1/2 Ton, in today's modern day Radials, 235-75R-15's seem to work.
Bill
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'60-'72 Chev/GMC Fan GMC 9500 Fan Detroit Diesel Fan |
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#4 | |
Registered User
Join Date: Aug 2011
Location: Northern California
Posts: 189
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Re: Need some help,
Quote:
The stock tire size indicated in most manuals is a bit smaller, though. G78-15 or H78-15, which equate to P215/75R15 and P225/75R15. A comparison chart with diameters and revolutions/mile here: http://www.angelfire.com/on/geebjen/tires.html
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1971 GMC C2500 Custom Camper - Second Owner. 350/TH350, Dana 60 Rear. |
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#5 |
its all about the +6 inches
Join Date: Jan 2001
Location: Hilliard Ohio
Posts: 2,693
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Re: Need some help,
at what speed is the speedo off by 15 MPH? I doubt you'll find a tire to make up that much.
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#6 |
Registered User
Join Date: Jul 2010
Location: PNW (Washington)
Posts: 75
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Re: Need some help,
Seems to be right round' 30, it says i'm doin 40-45ish. Could be the speedo gear though.Thanks for the help guys!
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