The middle bore is 4.25 on my rims .

 

Funny this thread should pop up... One of my 30" tires recently got shredded by a 4" section of 1/4" galvanized tubing while on my way to work one morning (it went all the way into the tire - it fell out when the guy at Les Schwab pulled the tire off the rim )... So, now I'm driving around on my spare which is an all-season radial and feels squishy compared to the other 3 LT's lol...

Anyway, I was thinking of buying new tires anyway and this kind of expedites the thought process somewhat only I want to run 33's which means I need to buy new rims since while I can find 33's that will fit on a 15x6 rim, they just seem a bit 'skinny'...

So now I'm looking at getting some 15x8 Allied Type 51 Daytona's (Black):
http://www.alliedwheel.com/wheel.php...lack%20Daytona

They list a 15x8; 5x5.5 bolt pattern; -19 offset; 3 3/4 backspace; 4.25 center bore; 1500 load rating...

From what I've read on this thread, everything looks about right - the backspace isn't quite 4" but I figure a 1/4" difference isn't going to matter that much. But, what's this -19 offset?

They also list a 15x7 rim with pretty much the same specs except it has a -6 offset and a 1600 load rating...

Is this offset value something to worry about or not?

 

Offset is how far off the center line of the wheel the mounting pad is. Positive offset is decreasing the distance in from the front of the wheel, negative offset is the opposite. The lesser the positive offset, the deeper the "dish" in the wheel, and vice versa.



The -19 should mean that the lug nut pads are 19mm off center toward the back of the rim. That number seems a bit high for only 1/4" difference.

To simplify, an 8" wide rim with 4" backspacing would have 0 offset. The same 8" rim with 3" backspacing would have a positive offset of about 25mm (25.4mm, to be exact.) As long as the backspacing is 3 3/4", you should be fine.

 

Hmmm.... Thx for the info... After looking over what you've said about backspacing and offset, the numbers Allied posted about this rim don't make much sense... I guess I'll have to actually look at one in person to see if it's what I want...

 

I have a 1976 F-150 Supercab 2WD and I've been looking at 20" or 22" rims. I've found that there are not alot of classic style rims that will fit the 5 x 5.5 bolt pattern with the center of 4.25. I'm having a hard time deciding which wheels to buy for my truck too. I would like to go with 22" in the rear and 20" in the front for the raked look.

 

There are also not many- if any- classic style rims that come in 20" or 22". If you look hard enough, wheels with the 4.25 center bore are out there. It just takes some time and research to find the ones you want. Try Craigslist, and check back there pretty often.

As far as the "raked" look, if your truck has the factory stance, you'll already have 3-4" difference from back to front...add 2" more from the wheels, and you may need to reinforce your seat belts...or add some padding to the dash for when you hit the brakes.

In the meantime, look for a thread on 2wd dents or lowered stance 2wd dents (not sure which, to be honest) and there are many pics in there of trucks with 20s and 22s. It doesn't look right to me, but to each his own.

Have fun exploring the site...there's a lot of very knowledgeable and helpful people here! Oh, and don't be afraid to ask questions, but try searching the threads for what you need before you do.

 

ive been looking used and a guy has a a set he said came off of his 76 he says his are like 3.5 (cant remember exactly) i checked my truck and the rim itself measures 4. something but the rim doesnt sit on the hub just the bolt pegs the center hole doesnt sit on any thing. then i measured the center hub and its like 3. something. is the center hole of the rim suppose to sit on the hub like a perfect fit? i checked the rear and the drum is smooth no hub. is the rim just suppose to sit on the pegs. were 76 different center bore size?
i just checked my ram and the rim does sit perfect on the hub

im confused any thoughts
(not sure if hub is the right word)

 

I don't think it matters if the center bore is larger than the hub diameter - only if it's smaller... The Allied rims I'm buying have a significantly larger center bore diameter which I think may be because they were designed to accommodate a variety of different axle/hub combo's - i.e. Ford 9"/Dana 40/Dana 60... The stock steelies off my 4WD truck fit my 2WD van yet the center bore is larger than the van's hub diameters... As long as the lug nuts are properly torqued, there shouldn't be a problem...

 

but did your vans stock rims sit on the hub?
that would mean anything over 3.5 or 3.7 would fit
in the other posts others have said it must be 4.25 but if it doesnt fit snug then whats the reason why?

 

The "stock" rims that came on this van were an optional rim known as a "styled steel rim" offered on the '78 and '79 ('80?) trucks vans and Bronco's - I just went out and measured the center bore on both the styled rims and the stock steelies and it measured out to be ~3.4 inches. The center bore on my Allied rims are 4.25 inches... The stock rims fit snug on the truck's hubs. I've been driving around for the past week on the Allied's - 60-miles/day - hauling stuff to the dump and whatnot and haven't noticed any problems... The only reason I can think of for the larger bore is to allow room for a center cap since I think the cap has be inserted through the back of the rim and is held in place by the pressure of the rim against the hub - maybe someone else has other ideas...

Here's a shot of what one of my Allied's looks like mounted to my truck:

 

OK, on my stock F100, the rear axle flange sticks out from the surface of the drum. The diameter of the axle flange is 4.25 inches. The wheel is supposed to fit AROUND the flange, not sit on top of it.

Post some pictures of your front hub and rear drum. Something on yours may have been changed along the way somewhere. I have never seen one of these trucks with a smooth rear drum and no axle flange.

Here are two pics of mine...



When the rear drums are on, the center flange of the axle is still proud of the outside of the drum. It isn't a whole lot, but it is enough. This is a stock 9" rear with a center flange diameter of 4.25 inches. The wheel itself should fit over the center flange.



Same deal with the front. The very inner flange (just before the mounting surface) is 4.25 inches in diameter. The wheel sits down around this flange also.

I don't know what you are looking at with yours, but if it doesn't look anything like these pictures, you need to post some pics. Otherwise, we'll just be shooting in the dark.

 

That's some clean brakes.

John, you might want to reposition the caliper key spring.

BTW: Got the stuff last week, and placed it in my glovebox...thanks!

 

Last Week I found a set of 20" x 9" Ultra Wheels 223/224 Goliath that fit my 1976 2WD F-150 Great. The ride and the braking performance is still perfectly fine. And the handling is greatly improved. I uploaded some new pictures of my truck with the wheels if you want to take a look. Below are the specs of the the wheels I have.
Size:20"x 9"
Back Spacing:5 3/4
Offset:+18
Bolt Pattern:5 x 5.5
Center Bore:108MM
Load Rating:2200
Weight:42LB

 

Paul's Supercab, those rims look good, and that is a sharp truck, but 20s just aren't my cup of tea. Even if they made 20" Torq-Thrusts, Halibrand slots, or other vintage wheel styles, I personally would still have to pass on 'em. But that's just my personal taste.

I must say, though, that each individual's different interpretation of the Dent adds yet another layer to the personalities of these great old trucks. That's just one of the great things about this site and its members...there's always a great deal of variety!

 

OK, so... Now I'm beginning to second-guess myself here... Does it matter if the center bore is larger diameter than the flange/hub? or should it fit snug (which is kind of what I think bonesbmx was asking)? When I checked on everything before buying my rims, I read that I needed a 4.25" center bore but, neither my hubs nor the flanges on the rear drum measure 4.25" so now I'm beginning to understand what bonesbmx is asking... As you can see in the picture I posted above, there is an obvious gap - does this not present a potential safety issue? All my lug nuts are torqued to spec and I've been checking them periodically to make sure... Am I just being paranoid (again)?...