What size lugnuts?? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

greenhorn male · 04-26-2005, 09:15 PM

What size lugnuts does a 1972 3/4T pickup use? Is it 1/2" or 9/16"

Mudder · 04-26-2005, 09:46 PM

My 3/4 ton is 9/16 if I remember and they are hard to find and pricey.

greenhorn male · 04-26-2005, 10:12 PM

I know they are pricey. That's why I want to make sure. My 2wd 3/4T lugnuts don't say anything on them. With a tape measure it looks close to 9/16" top of thread and about 1/2" valley of thread. In other words, the inside diameter of the nut before threads were cut is closer to 1/2". They are selling a set of 8-lug lugnuts online @ 9/16", but list the application as 73-87.
Does anyone know for sure the different lugnut sizes for 67-72 trucks?

Longhorn Man · 04-26-2005, 10:53 PM

3/4 ton and one ton SRW had 1/2 inch untill 71, when they went to 9/16.

greenhorn male · 04-26-2005, 11:15 PM

This is getting confusing. This is what one websites wheel bolt chart says:

65-87 C-10 PICKUP 2WD 5 on 5 in. 1/2
69-87 PICKUP 4WD 6 on 5.5 in. 7/16
69-91 BLAZER / SUBURBAN 4WD 6 on 5.5 in. 7/16
65-87 3/4 & 1 TON C20 C30 2WD 8 on 6.5 in. 9/16
PICKUP / SUBURBAN 2WD
65-87 3/4 & 1TON K20 K30 4WD 8 on 6.5 in. 9/16
PICKUP / SUBURBAN 4WD

Longhorn Man · 04-26-2005, 11:22 PM

they are wrong.

Mudder · 04-26-2005, 11:28 PM

Mine is a 79 and they are 9/16

greenhorn male · 04-26-2005, 11:38 PM

Andy,
Are you saying my 72 C2500 should be a 9/16". Is it possible they retained the '71 1/2". I was going to order the newer style conversion lugnuts (threaded inside and outside for new style caps) tonight, but I guess I'll wait until I know for sure. I wonder if Kragens sells individual nuts or would any coarse 9/16" nut from a hardware store have the same tread as 9/16" wheel studs.

**JIMs70GMC** · 04-27-2005, 03:46 AM

My 70 has 1/2" and my 71 has 9/16", both 3/4 ton 4wd.

EROC · 04-27-2005, 05:40 AM

The 71 3/4 frontend I just bought has 9/16. To tell for sure take a 1/2 and 9/16 open end wrench and try to put it on your wheel studs. If they're 9/16 studs the 1/2 wrench won't go and the 9/16 will fit pretty close.

chickenwing · 04-27-2005, 01:11 PM

Unless they are something special... Why not pick em up on your next recreational junk yarding trip. Wrong or not, I consider that a freebie for the admission charge.

stllookn · 04-27-2005, 04:31 PM

greenhorn...they are fine threads, not coarse. Just measured my '68 3/4 t. and they are 1/2-inch. My '72 3/4 t. is 9/16. I think Andy has it right...who would question the Longhorn Man...not me...LOL!

Longhorn Man · 04-27-2005, 06:26 PM

shoooot, question me all you want, I get proven wrong every day on here.
However, i do know that the 9/16 lug started in 71 with the hainge to disc brakes.
My first truck '70 CST/20 longhorn....1/2 inch stud. I know this becouse the wheels were for 9/16 studs, and I was almost concerned at first.
2nd truck don't count, it was a little 1./2 ton. (7/16 though if you are wondering)
3rd truck, '70 C/30 longhorn. 1/2 inch studs. Again realized when I put later wheels on it, almost got concerned, but then remembered the first truck and said...Bah, I ain't worried.
Now, 4th truck...or parts b!tch...how ever you wanna look at it, 1971 CST/20 Longhorn. 9/16 stud. Realized when I went to put an older wheel/tire combo becouse it helfd air...much easier to push....no fit.

plus I read it in the books.

And on here years ago when I asked about the first truck and the lugs being smaller than the wheel holes.

greenhorn male · 04-27-2005, 08:25 PM

I just purchased the conversion lug nuts on ebay a few minutes ago. They are 9/16 with the outside threads to install newer style wheels and caps. I want to see how they look with the newer steel wheels with beauty rings and dually caps on 4 corners. Thanks for all the help.

Robert1970C20rstbukt · 04-27-2005, 09:36 PM

On my 1970 C20, they're 1/2" lugs.
On the rear end of a '72 GMC 1 ton I have, they're 9/16" lugs.

What Longhorn man said is right. They went to 9/16" studs/lugs in '71, so everything before '71 has 1/2" studs/lugs.

04-26-2005, 09:15 PM	#1
greenhorn male Senior Member Join Date: Jan 2003 Location: Bay Area, Northern California Posts: 1,344	What size lugnuts?? What size lugnuts does a 1972 3/4T pickup use? Is it 1/2" or 9/16" __________________ 03 Tahoe 72 GMC Super Custom 2500 Custom Camper, my reliable workhorse. Dual gauged tanks, dual battery trays.

04-26-2005, 10:12 PM	#3
greenhorn male Senior Member Join Date: Jan 2003 Location: Bay Area, Northern California Posts: 1,344	I know they are pricey. That's why I want to make sure. My 2wd 3/4T lugnuts don't say anything on them. With a tape measure it looks close to 9/16" top of thread and about 1/2" valley of thread. In other words, the inside diameter of the nut before threads were cut is closer to 1/2". They are selling a set of 8-lug lugnuts online @ 9/16", but list the application as 73-87. Does anyone know for sure the different lugnut sizes for 67-72 trucks? __________________ 03 Tahoe 72 GMC Super Custom 2500 Custom Camper, my reliable workhorse. Dual gauged tanks, dual battery trays.

04-26-2005, 11:15 PM	#5
greenhorn male Senior Member Join Date: Jan 2003 Location: Bay Area, Northern California Posts: 1,344	This is getting confusing. This is what one websites wheel bolt chart says: 65-87 C-10 PICKUP 2WD 5 on 5 in. 1/2 69-87 PICKUP 4WD 6 on 5.5 in. 7/16 69-91 BLAZER / SUBURBAN 4WD 6 on 5.5 in. 7/16 65-87 3/4 & 1 TON C20 C30 2WD 8 on 6.5 in. 9/16 PICKUP / SUBURBAN 2WD 65-87 3/4 & 1TON K20 K30 4WD 8 on 6.5 in. 9/16 PICKUP / SUBURBAN 4WD __________________ 03 Tahoe 72 GMC Super Custom 2500 Custom Camper, my reliable workhorse. Dual gauged tanks, dual battery trays. Last edited by greenhorn male; 04-26-2005 at 11:21 PM.

04-26-2005, 11:38 PM	#8
greenhorn male Senior Member Join Date: Jan 2003 Location: Bay Area, Northern California Posts: 1,344	Andy, Are you saying my 72 C2500 should be a 9/16". Is it possible they retained the '71 1/2". I was going to order the newer style conversion lugnuts (threaded inside and outside for new style caps) tonight, but I guess I'll wait until I know for sure. I wonder if Kragens sells individual nuts or would any coarse 9/16" nut from a hardware store have the same tread as 9/16" wheel studs. __________________ 03 Tahoe 72 GMC Super Custom 2500 Custom Camper, my reliable workhorse. Dual gauged tanks, dual battery trays.

04-27-2005, 03:46 AM	#9
JIMs70GMC user # 2756 Join Date: Jun 2001 Location: Chesapeake, Virginia Posts: 4,612	My 70 has 1/2" and my 71 has 9/16", both 3/4 ton 4wd. __________________ 1970 K25, 8' stepside bed 350/465/205 44 up front, 60 in the rear 4.10s rolling on 33" Dunlop MTs 1986 K5, 350/465/208 Dana 60/14 bolt from a cucv 36" Super Swampers TSL/SX 1983 K20 w/ CUCV axles, 350/700R4/208 sitting on 37" Goodyears 1986 M1031 6.2 diesel, TH400/NP205 locker in the rear and a LS in the front, all stock for now..... 1986 K30, 350/400/205 dana 60 and 14 bolt. I kept the drivetrain. Body/bad and chassis are gone. 1981 K30, 350/465/205 dana 60 and dually 14 bolt. Has a G80, and a flat bed. Going to replace the flat bed. 1985 K20, 350/400/208 10 bolt and SF 14 bolt. I wonder where I can find some 1 tons. Hmmmmm

04-26-2005, 09:46 PM	#2
Mudder Registered User Join Date: Feb 2001 Location: East Central, MO Posts: 11,336	My 3/4 ton is 9/16 if I remember and they are hard to find and pricey.

04-26-2005, 10:53 PM	#4
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,690	3/4 ton and one ton SRW had 1/2 inch untill 71, when they went to 9/16.

04-26-2005, 11:22 PM	#6
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,690	they are wrong.

04-26-2005, 11:28 PM	#7
Mudder Registered User Join Date: Feb 2001 Location: East Central, MO Posts: 11,336	Mine is a 79 and they are 9/16

04-27-2005, 05:40 AM	#10
EROC Active Member Join Date: Jan 2005 Location: Salem,Virginia Posts: 123	The 71 3/4 frontend I just bought has 9/16. To tell for sure take a 1/2 and 9/16 open end wrench and try to put it on your wheel studs. If they're 9/16 studs the 1/2 wrench won't go and the 9/16 will fit pretty close. __________________ 69 GMC 2500 Camper Special 88 S10 Pickup 04 Impala I ship UPS from 24153

04-27-2005, 01:11 PM	#11
chickenwing Lovin' Life in Miss.! Join Date: Mar 2004 Location: Puckett, Mississippi Posts: 1,937	Unless they are something special... Why not pick em up on your next recreational junk yarding trip. Wrong or not, I consider that a freebie for the admission charge. __________________ The truck... you hear that? No really, you did hear that?!!!

04-27-2005, 04:31 PM	#12
stllookn Saving 1 truck at a time! Join Date: Aug 2001 Location: Kent, WA Posts: 6,465	greenhorn...they are fine threads, not coarse. Just measured my '68 3/4 t. and they are 1/2-inch. My '72 3/4 t. is 9/16. I think Andy has it right...who would question the Longhorn Man...not me...LOL! __________________ '68 C20 Longhorn 50th Anniversary 400/TH400 '68 C20 Longhorn 50th Anniversary 468/TH400w/buckets '72 C20 Halfhorn (Longhorn w/o cab and front clip) '69 Flxible Cruiser (look up ugly in the dictionary)

04-27-2005, 06:26 PM	#13
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,690	shoooot, question me all you want, I get proven wrong every day on here. However, i do know that the 9/16 lug started in 71 with the hainge to disc brakes. My first truck '70 CST/20 longhorn....1/2 inch stud. I know this becouse the wheels were for 9/16 studs, and I was almost concerned at first. 2nd truck don't count, it was a little 1./2 ton. (7/16 though if you are wondering) 3rd truck, '70 C/30 longhorn. 1/2 inch studs. Again realized when I put later wheels on it, almost got concerned, but then remembered the first truck and said...Bah, I ain't worried. Now, 4th truck...or parts b!tch...how ever you wanna look at it, 1971 CST/20 Longhorn. 9/16 stud. Realized when I went to put an older wheel/tire combo becouse it helfd air...much easier to push....no fit. plus I read it in the books. And on here years ago when I asked about the first truck and the lugs being smaller than the wheel holes.

04-27-2005, 08:25 PM	#14
greenhorn male Senior Member Join Date: Jan 2003 Location: Bay Area, Northern California Posts: 1,344	I just purchased the conversion lug nuts on ebay a few minutes ago. They are 9/16 with the outside threads to install newer style wheels and caps. I want to see how they look with the newer steel wheels with beauty rings and dually caps on 4 corners. Thanks for all the help. __________________ 03 Tahoe 72 GMC Super Custom 2500 Custom Camper, my reliable workhorse. Dual gauged tanks, dual battery trays.

04-27-2005, 09:36 PM	#15
Robert1970C20rstbukt Registered User Join Date: Jun 2004 Location: Beeville, Texas Posts: 1,943	On my 1970 C20, they're 1/2" lugs. On the rear end of a '72 GMC 1 ton I have, they're 9/16" lugs. What Longhorn man said is right. They went to 9/16" studs/lugs in '71, so everything before '71 has 1/2" studs/lugs. __________________ RJD 1984 Chevrolet C30 welding truck 454/SM465 1977 GMC C15 pickup 350/TH350 1970 Chevrolet C20 pickup 350/TH400 1970 Chevrolet K20 Suburban 454/TH350 1969 GMC 8500 478M V6/5 spd winch truck



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