Can I swap 7 1/2 x 16 wheels for 8 x 16.5 from a Chevy dually truck?

[brians1969]

Sent: 5/22/2007 4:48 AM

I have a 69 with 7 1/2 x 16(thats what it says on the tires) with split rims. Someone I know is parting a 77 Class C GMC dually 10,500 GVW with 8 x 16.5 (thats what it says on the tires). Can I use these wheels? Will my speedometer be off?
thanks
brian

[rustyescott1]

Sent: 5/22/2007 4:33 PM

sorry can't use chevy 8lug dully wheel on dodge m/h chaisse.must use 8 lug coined wheel. ford or dodge. but ford/dodge 8 lug wheel will fit chevy do to center hole being bigger.hope this helps rusty escott

[Slantsixness]

Sent: 5/22/2007 4:57 PM

Rusty is right, to a point. the center hub diameter is different, but the lug hole on a GM truck rim are too small to fit over the Dodge lugs.

I don't believe the lugs on a 67-71 chassis are coined either, in most cases.

As far as the tire sizes, the 7.00-16.5 and the 7.00-16.5's are exactly the same outer diameter, so it won't affect your speedo, if you could mount the rims.

You can find 16, 16.5 and 17.5 inch 8 lug non-split rims that'll fit your motorhome quite easily, they're on any ford or Dodge 1 ton dually truck up to 1997, or any class C (Ford or dodge) or ice cream truck, potato chip truck, stake body or wrecker. If it's a Dodge or Ford, they'll fit. (8 lug pattern ONLY.. the 5 lug budd wheels are a different animal, as well as the 6 lug wheels from 67-68). Later model (87 up) Ford wheels with the hub insert plate will require longer wheel studs in the front.. and the ford lugs won't fit the old dodge brake drums, so they would have to be new longer replacements, but they are available.
Best fit would be 74-up Dodge motorhome wheels, class C or A, in 16 or 17.5". The 17.5's are easy to find, but there are only a few tire choices.

Because you don't have the coined rims (likely) you would have to replace the rear dually's as a complete set. Don't mix and match coined and non-coined rims, or split and non split rims, it's a recipe for disaster.

Tom

[brians1969]

Sent: 5/22/2007 6:00 PM

Ok, thanks....in the junkyard I remember seeing a mid 70's dodge class c with (i think) 8 x 16.5 would those work?

I believe mine are coined...alternate dimple in and out.
Would those(in the junkyard) be usable if they are not coined? Does coining lock the dually wheels in the rear together?

thanks
brian

[LonghouseIndian]

Sent: 5/24/2007 10:14 AM

OK, what are coined wheels?
Also, while on the subject, I read somewhere here that the wheels (5 lug Budd) don't center themselves. What's that about? How do you get them centered?
Thanx, Aaron

[Slantsixness]

Sent: 5/24/2007 10:49 AM

"coined" rims have alternating concave recesses in the lug holes on bothe sides of the bolt circle, and require a  collared lug nut, kind of similar to a reversed Acorn style lug nut.  When used in a dually application, the rims will only fit together in a certain clocked arrangement. Also, there is an alignment pin (which sometimes has been removed) that also clocks the wheels to align the Schrader valves on the dually rims.

The actual hubs are also coined, allowing the rims to fit correctly only every other position. (meaning the wheels can only be installed correctly in one of 4 positions.)

With that said, if the alignment pins are still intact, both dually wheels have to be clocked so that the alignment pin holes line up, and only installed in the clocked position with the alignment pin. This only applies to the rear dually wheels, there is usually no alignment pin inthe front, but there is usually a place to install one on the front hubs if you wanted to. It's a 1/4" solid roll pin. Probably best not to remove it, unless you use later model rims that do not have the alingment holes (Some Ford rims are like this)

The 5 lug budd rims will self align, if installed properly with the correct lug nuts and studs. the trick there is to install the wheel with great care to tighten the lugs in an even pattern, and certainly not with an impact gun, as they are fine threaded, and strip very easily considering the amount of force necessary to remove them. The inner stud nuts on the rear wheels ar a bear, and great care should be taken in using both the proper tools and procedures to remove them. You can see the correct alignment by looking for an even gap between the hub hole in the wheel and the hub, if it looks close, it's aligned, if it's wrong, it will be obvious, and the stud length protruding from the lug nut will be different (more or less protruding threads, sometimes, the threads won't protrude at all if the Acorn is caught on the wheel face.

A look around the message boards here will show you some of the woes of improper wheel mounting, (it usually comes uo in Brake and tire discussions). Several members have added pictures to show you exactly what you might be up against, which typically includes the fact that the wheels have been on the motohome for over 20 years, making it pretty hard not to damage lugs and studs, or just plain damn hard to get them loose!  Famously, Tire stores will strip the left hand threaded lugs on the left side of the vehicle. The studs are stamped LH, along with the lug nuts. (Typically, this is only on 71 and prior year Dodge chassis, but there are indeed 72's with 71 chassis, so be careful to look!)

Tom

[Froggy1936]

In response to Longhouse, There is no such thing as coined wheels. (as i mentioned before that i had never heard of them in 60 years of being a mechanic) It is a spelling error that has taken root, The proper term is coned refering to the cone at the bolt hole . Somewhere along the line someone added a i and it stuck  Frank 

[GWINGER]

That makes better sense, the coined term was kooky.
J

[Oz]

Very good piece of info, Frank.  But, when you search the messages for anything in relation to that, youl'll need to use the misnomer "coined" as that is what all us, less knowledgeable folks have related it to.

[DaveVA78Chieftain]

Just for reference, you will see both terms referred to in the Dodge Service manual.  When they talk about the physical shape, they use "coned".  When talking about using them to align the rims up, they use "coined".

Dave