How to ID 16" 8 bolt wheels?

Hello,

I have a '79 k20 Suburban that had OEM 16.5 x 9.5 tires & rims.

Long story short: was provided with 4x 16" 8 bolt rims that fit the truck fine with correct appearing hub bore fit.

But OEM hubcaps don't fit these 16" rims. I had assumed that was merely some difference between the gm 16.5 and 16" gm rims.

I want to find hub caps that fit these 16" wheels.

Now recently NOT having a 16" spare and my last 16.5 tire approaching 25 yrs old, I went to salvage yard and found a nice 8 bolt 16" wheel off an older chevy van to be my new 16" spare.

I get it home and for giggles, I try the old 16.5" oem hubcaps: they fit like a glove !

So what in the heck are the four 16" wheels I am currently running on the truck where th oem gm hubcaps don't fit?

Old dodge or ford rims with the same hub bore? Or some different oem GM wheel. How can i tell and more importantly WHAT hub caps will fit them wheels?

The truck looks ok without the caps but seems somewhat 'naked' appearing. I'd like to have some no brand or chevy caps to cover up the bolts.

I've spent hours online to ID what 16" wheels I have, & find a solution, but NOT having much luck.

WHAT rims are on the truck and what trim/center cap or oem caps would work with them.

THANKS

PHOTOS:
16" up front; and OEM 16.5's in front with caps and 16" in back(old photo)

My truck came to us wearing a set of Ford wheels.
There is a Ford stamp on each of them proclaiming so.

I can see yours have some stamps on them, is there a makers mark on the front or the back?

Those wheels kind of look like GMT400 wheels. They never had hubcap rings like the older squarebody wheels. They came with plastic center caps.

Here is a link that shows what I think you have. https://www.ebay.com/itm/1866461150...iDbKPJ1SMS&var=&widget_ver=artemis&media=COPY

mcarlo86 said:

Those wheels kind of look like GMT400 wheels. They never had hubcap rings like the older squarebody wheels. They came with plastic center caps.

Here is a link that shows what I think you have. https://www.ebay.com/itm/1866461150...iDbKPJ1SMS&var=&widget_ver=artemis&media=COPY

Click to expand...

Yep, those are the later style wheels.

Yes those are GMT 400/OBS 8 lug wheels. I have a set of my crew cab. They use a stainless steel trim ring and a plastic center cap (either chrome or black). The GMT 400 trucks also used a full wheel covers in stainless steel on these wheels, instead of the trim ring and center cap.
These are 16" x 6.5" wheels, usually run a 245/75R 16 or a 265/75R16 tire.
I attached some pictures: brochure from mid 70s showing the dog dish caps and white wheels the 8 lug squares got; basic white wheel with no cap, probably a 16.5"; the GMT 400 and late square body full wheel covers that fit the 16" steel wheels (these came off my '90 R2500 Burb and currently live in Illinois, sold em couple months ago) and the silver steel wheel with trim ring and chrome (Silverado) plastic center cap, on my '97 C3500 crew cab. These center caps are held on by plastic lug nut covers that thread onto threads on the lug nuts. The OBS trucks use a metric lug nut and stud, but I have seen a SAE version of this lug nut.

I'm told 16.5" tires are rather hard to find and quite expensive when you do find them. By the time the OBS trucks came on the scene, GM had phased out the 16.5" in favor of the 16" tires and wheels. Old Burb had white wheels under the full wheel covers; I pulled the covers to clean them up and repaint the emblems. Then they never got back on the truck, was gonna put alloys on it and then that didn't happen either.
I have a set of 16.5" aluminum slot mags that nobody wants, because of the tire issue....

HotWheelsBurban said:

I'm told 16.5" tires are rather hard to find and quite expensive when you do find them. By the time the OBS trucks came on the scene, GM had phased out the 16.5" in favor of the 16" tires and wheels. Old Burb had white wheels under the full wheel covers; I pulled the covers to clean them up and repaint the emblems. Then they never got back on the truck, was gonna put alloys on it and then that didn't happen either.
I have a set of 16.5" aluminum slot mags that nobody wants, because of the tire issue....

Click to expand...

I wouldn't say nobody.

bucket said:

I wouldn't say nobody.

Click to expand...

Well.... nobody wants them at the swap meets I've had em at in Texas. I had one dude who had the bigger ones on a lifted Blazer, but he didn't want to buy the whole set(and I didn't want to get stuck with two wheels I don't need). I don't want to sell them for scrap either, if someone could use them....

Thanks HotWheelsBurban!

I think i picked up some correct 8 x 6.5 plastic chevy center caps today:

But where do I find the SAE lug nuts you mentioned that would work with my old K20 studs and allow the 'new' center caps to thread on?

I've only seen metric so far.

Thanks again, Pete

HotWheelsBurban said:

I'm told 16.5" tires are rather hard to find and quite expensive when you do find them. By the time the OBS trucks came on the scene, GM had phased out the 16.5" in favor of the 16" tires and wheels. Old Burb had white wheels under the full wheel covers; I pulled the covers to clean them up and repaint the emblems. Then they never got back on the truck, was gonna put alloys on it and then that didn't happen either.
I have a set of 16.5" aluminum slot mags that nobody wants, because of the tire issue....

Click to expand...

If you have a 8 lug trailer, they would be great for that.
(16.5 trailer tire can be had okay priced, esp for a heavier duty tire)

Catbox said:

My truck came to us wearing a set of Ford wheels.
There is a Ford stamp on each of them proclaiming so.

I can see yours have some stamps on them, is there a makers mark on the front or the back?

Click to expand...

These are fords right?

I ask because I can go shove a dog dish on each one(well I dont own the wheel at the end anymore) the front ones with the hole for the hub locker and the one with the GMC logo
I wonder if the 16.5 wheels had the same size ring , because Im pretty sure my caps are from my truck and my truck had 16.5 from factory.

These were likely original to a square with 16.5 or my truck specifically (white, would be the original painted wheel color for my trucks color scheme)

These would work?

hypercycle said:

These would work

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they would work on a gmt400.

you can do two things, 1 replace your studs and have them thread proper

Or just YOLO and use a drill or a small impact and install them over an SAE lugnut with threads(It sounds like you found the lugnut that works for your truck, but you want the outer threads to match the hub cap?)

The plastic will yield to being YOLO'ed, probably even cut the thread into the one that lets you remove them and install in the future.

but 22mm is the socket size I use on my gmt800 (With the lugnuts being entirely metric), so that may work. Im not sure if the hub caps arte m27x2.0

But I did google it, it seems to be correct. You can replace the black plastic ones if they werent that thread size, meaning its workable either way. Get those lug nuts if its a good seller, try em out. Make sure to compare the taper (60 degrees) , to be sure you have the right one

AuroraGirl said:

they would work on a gmt400.

you can do two things, 1 replace your studs and have them thread proper

Or just YOLO and use a drill or a small impact and install them over an SAE lugnut with threads(It sounds like you found the lugnut that works for your truck, but you want the outer threads to match the hub cap?)

The plastic will yield to being YOLO'ed, probably even cut the thread into the one that lets you remove them and install in the future.

but 22mm is the socket size I use on my gmt800 (With the lugnuts being entirely metric), so that may work. Im not sure if the hub caps arte m27x2.0

But I did google it, it seems to be correct. You can replace the black plastic ones if they werent that thread size, meaning its workable either way. Get those lug nuts if its a good seller, try em out. Make sure to compare the taper (60 degrees) , to be sure you have the right one

Click to expand...

The lug nuts are 14mm threads on the GMT 400, 5 lug and 8 lug. The difference between the lug nuts on my Burb and my crew cab is the Burb ones don't have the external threads on the top, that the plastic covers thread onto, and the crew cab ones do have those. Those covers are what holds the center cap onto the wheel. I personally prefer the 400 style caps over the 800 style as in my opinion the 400 is a cleaner, less fussy design.

I guess I need to confirm what the threads on my 1979 k20 4x4 suburban actually are: I assumed 9/16-18; those lug nuts I pictured above seem to be these SAE inner threads with the dual 'outside' threads being in a metric standard M27x 2.0; The center caps I bought are off a 2000 8 bolt ?Silverado? I was trying to see if that was the correct outside thread for those caps. Can't readily find this information online for some reason. Thank you AuroraGirl for also looking. Since I have the caps in hand, I guess I can match up those threads as well and hope the are the M27 x 2.0 so I can move on
Thank you, Pete