y5mgisi
1 ton status
So i think i want to get some original white steel wheels and run gmc hubcaps on my 78 3/4ton. How do i know what ever wheels i find in CL are right? Are they coded?
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How can i find correct wheels for my 78?
- Thread starter y5mgisi
- Start date
Irish1941
1/2 ton status
Yep. All GM steel wheels are dated coded. Sometimes inside the wheel on the hoop but most I've come across are on outside, close to valve stem. Seen the codes on the backside too.
Just did steelies on my truck and all the wheels were all date coded 05-01-85.
Sometimes they have month day year and sometimes just month & year.
Let me find a picture.
Should look something like: DOT 1 Made in USA 15x7 JJ 10-76 1800lbs 45psi
If you are within 6 months of build date it's considered "correct"
Just did steelies on my truck and all the wheels were all date coded 05-01-85.
Sometimes they have month day year and sometimes just month & year.
Let me find a picture.
Should look something like: DOT 1 Made in USA 15x7 JJ 10-76 1800lbs 45psi
If you are within 6 months of build date it's considered "correct"
Irish1941
1/2 ton status
Couldn't find the photo of the plain steelie but this is off the backside of the spare rally wheel for my '89. Same idea.
Coded 08 22 88. They coded them as far back as the '40s. Reason being if there was a wheel failure they could pin point the dates.
Hope this helps.
As for going white steel wheels, I'd vote yes.
Coded 08 22 88. They coded them as far back as the '40s. Reason being if there was a wheel failure they could pin point the dates.
Hope this helps.
As for going white steel wheels, I'd vote yes.
y5mgisi
1 ton status
Thanks man! I LOVE those wheels! I guess I'm not quite concerned with them being date correct as i am making sure It's physicaly the same as what would have come from the factory in terms of back spacing, hub cap "bumps", etc. So what would be really nice to know is along with the date coding, what other code information i would need to be on the lookout for.
y5mgisi
1 ton status
Maybe I could check out the spare tire on my truck? 
Irish1941
1/2 ton status
Glad to help.
You could look for part numbers via GM book then cross reference what you find in the yards. Being it's a 3/4 ton, I think they are gonna be 16.5 x 7 but I have seen 16.5 x 8 plain steel wheels before. Some of the early 2WD Camper Specials('71-'75?) had factory wide 16.5s. Something like 8.25 and/or 9.25" wide.
And for sure look at your spare. It'll give you everything you need.
You could look for part numbers via GM book then cross reference what you find in the yards. Being it's a 3/4 ton, I think they are gonna be 16.5 x 7 but I have seen 16.5 x 8 plain steel wheels before. Some of the early 2WD Camper Specials('71-'75?) had factory wide 16.5s. Something like 8.25 and/or 9.25" wide.
And for sure look at your spare. It'll give you everything you need.
I got my rallies. Now just need the hub caps. Lemme know where u get them from when u do
y5mgisi
1 ton status
Im really hoping to get a 16" in whatever i get. I know my old 73 had factroy 16 x 6.5 or 7 on it. If they came factory with 16.5 i guess thats what i'll get, but would like to stick with 16.
Irish1941
1/2 ton status
Glad to help.
You could look for part numbers via GM book then cross reference what you find in the yards. Being it's a 3/4 ton 4WD, I think they are gonna be 16.5 x 7 but I have seen 16.5 x 8 plain steel wheels before. Some of the early 2WD Camper Specials('71-'75?) had factory wide 16.5s. Something like 8.25 and/or 9.25" wide.
And for sure look at your spare. It'll give you everything you need.
As for hub caps, pretty sure somewhere around '61-'62(could be '66?) they changed from snap inside to snap outside so that shouldn't be an issue. I know for a fact the '71 up wheels will take the '76 up cap and vise versa. Plus in '71 disc brakes became standard on all GM trucks so wheels will be same backspace wise but just watch out because some rims were for front axle and some were just for rear, with rear having having real deep backspace.
You could look for part numbers via GM book then cross reference what you find in the yards. Being it's a 3/4 ton 4WD, I think they are gonna be 16.5 x 7 but I have seen 16.5 x 8 plain steel wheels before. Some of the early 2WD Camper Specials('71-'75?) had factory wide 16.5s. Something like 8.25 and/or 9.25" wide.
And for sure look at your spare. It'll give you everything you need.
As for hub caps, pretty sure somewhere around '61-'62(could be '66?) they changed from snap inside to snap outside so that shouldn't be an issue. I know for a fact the '71 up wheels will take the '76 up cap and vise versa. Plus in '71 disc brakes became standard on all GM trucks so wheels will be same backspace wise but just watch out because some rims were for front axle and some were just for rear, with rear having having real deep backspace.
y5mgisi
1 ton status
This is pretty much what im going for. Though these look like 16.5's.
y5mgisi
1 ton status
Looks like they would have been 16.5's.
Irish1941
1/2 ton status
Pretty much as I remember.
Don't recall seeing just a 16" on a 3/4 ton after '72.
Most tire companies still make 16.5 tires in popular sizes so you should be good to go.
Those 9.5" would be killer in white with factory hubcaps.
Don't recall seeing just a 16" on a 3/4 ton after '72.
Most tire companies still make 16.5 tires in popular sizes so you should be good to go.
Those 9.5" would be killer in white with factory hubcaps.
y5mgisi
1 ton status
That is true.
y5mgisi
1 ton status
Crappy pics, but these are the wheels i want.
Irish1941
1/2 ton status
Yeah can't beat a steelie with factory cap.
Quick search brought this up:
http://coloradok5.com/forums/showthread.php?t=261517&page=2
Good pix at the bottom of the thread
Quick search brought this up:
http://coloradok5.com/forums/showthread.php?t=261517&page=2
Good pix at the bottom of the thread
Im not sure if there are 16" steelies that allow these hub cabs, im sure Martin could tell you for sure. I will tell you that the 16.5's do for a fact.
Here are some of my pics to help you find a set.
Here are some of my pics to help you find a set.
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Hey irish, Are those just rally's or are they wagon wheels? Id like to put the hub caps like those on my rallys.
