Can I change from 8.75x16.5 to 16 or 17" Wheels?

Vanner · July 31, 2018, 09:30 AM

Hello, I just recent bought this 1978 Dodge Brougham 18ft. I am used to 70's Dodge Tradesmans but not too familiar with RVs. I was looking into putting Slot Mags on my RV but then I started learning about coined wheels. Now the wheels that are on there now don't look coined but I haven't removed the wheels to see if the hub is coined too. This coined thing is all new to me. What are the pro and cons of doing this? I haven't seen any RV's with anything but Dully wheels so I wondering if it's even possible. Thanks for the help!

Froggy1936 · July 31, 2018, 12:04 PM

Vanner, This is a pet peeve of mine But since you are new i will explain it again ! There is no such thing as coined wheels . The proper defination is CONED ! Due to a misprint way back in the 1950,s in a Dodge service manual the I was inserted into the word ! The holes are coned like an ice cream cone . You are welcome Frank ! As far as useing 16" wheels you will have to get one with the proper coned hole spaceing , install the wheel on the veh frt and rear if it clears the caliper/drum you can use them . 16,s will cut MPG and raise speedometer readings 17,s will increase MPG and lower speedometer reading !

Rickf1985 · July 31, 2018, 07:00 PM

The aluminum wheels will have to be either lug centric or hub centric so that they do not egg out the holes. The conned holes on the steel wheels are there to retain the torque on the lug nuts and keep the wheel from moving around, it is centered on those cones. Aluminum does not have the spring to it that steel has so it cannot use that theory. You are probably best off staying with steel rims. If you plan on keeping the van for a long time then 17's would be the way to go since 16's are now on the way out like 16.5's used to be. They will be around for quite a while since they were used well into the late 90's but then the 17's started coming in. You can get 17" tires that will match the height of the ones you are running now so that the speedo will stay the same.

Vanner · July 31, 2018, 11:05 PM

Thank you both for your help and info, Coned, got it. Now, the wheels on the RV right now don't look coned. I read the coned wheels would have alternating innies and outties. I was wondering if maybe some RVs with a short wheel base (18ft) and a van chassy might use plain 8 lug wheels? This is the drivers side front and this doesn't look coned to me.

Vanner · July 31, 2018, 11:13 PM

I haven't taken the wheel off yet to see if the rotor/hub is coned as well. Isn't that the case where the wheel has to match up with the alternating innies and outties? Sorry, I just want to get this right before I buy newer wheels. I'd like the run 17x10 in the back and fill up the wheel well.

postman · July 31, 2018, 11:15 PM

Those are not "CONED" lug nuts. So you may be correct (maybe).

Rickf1985 · August 01, 2018, 07:51 AM

They are a standard tapered lug nut and that area of the rim where the lugs are is raised just a bit to proved tension. The holes are well worn so you do not see the corresponding taper on the hole. No, they are not the "coned" type that we are talking about in relation to the dual wheel setups.

skloon · August 01, 2018, 01:11 PM

I think this is what coned means

Vanner · August 01, 2018, 01:22 PM

Iâ€™m thinking my RV does not require coned wheels.

Rickf1985 · August 01, 2018, 04:53 PM

It does not if it has single wheels, but you have eight lug wheels which means 3/4 or 1 ton vehicle so you might not find aluminum wheels in any kind of decent price range that will stand up.

Vanner · August 01, 2018, 06:08 PM

It has single wheels all the way around.

postman · August 01, 2018, 11:53 PM

Quote from: Vanner on August 01, 2018, 06:08 PM
It has single wheels all the way around.

Hm?

TerryH · August 02, 2018, 01:01 AM

Quote from: postman on August 01, 2018, 11:53 PM
Hm?

Actually the late 70's Dodge Brougham chassis was used extensively for class B RV's, single wheel rear.
It was also used to a lesser degree for class C's in the lower length models with duals, but singles were the norm.

postman · August 03, 2018, 01:03 AM

"coned" rims were/are indexed as are the hubs.

chicknnhead · August 07, 2018, 02:39 PM

Vanner welcome to the site, with a name like vanner i'm sure you know of those van message boards as well...i'm on those as well

only the dually wheels were coned wheel. with that said yours with the rear with the single wheel looks odd, i'm wonder if that is rupposed to be a dual rear wheels and they switched it because your rear end looks extactly like mine. some of the rvs did come with single 8 lug front wheels and dually rear wheels, and people complained because you then had to care two spares depending on which flat you have. foot for thought anyway

Also you mentioned your was a 78, based a a few things i see your actually van body is a 77. a lot of times RV companies would order a bunch of chassis at one time, but by the time they got to some of them the next year might have already been under way. and were titled as 78's. 71-77 vans were the the same, 78 was one year only on a lot of things, then 79+ were the same. based on the fender marker lights your van is 77. 78's were rectangle and the dash on a 77 is completely different then 78.

Also welcome to the brougham club...i'm alos a member, they went out in the mid 80's. i have had mine for 13 years, this pic was taken last weekend

can't believe it has been 8 years since i have started this thread.....

Rickf1985 · August 07, 2018, 05:09 PM

Quote from: chicknnhead on August 07, 2018, 02:39 PM
Vanner welcome to the site, with a name like vanner i'm sure you know of those van message boards as well...i'm on those as well

only the dually wheels were coned wheel. with that said yours with the rear with the single wheel looks odd, i'm wonder if that is rupposed to be a dual rear wheels and they switched it because your rear end looks extactly like mine. some of the rvs did come with single 8 lug front wheels and dually rear wheels, and people complained because you then had to care two spares depending on which flat you have. foot for thought anyway

Also you mentioned your was a 78, based a a few things i see your actually van body is a 77. a lot of times RV companies would order a bunch of chassis at one time, but by the time they got to some of them the next year might have already been under way. and were titled as 78's. 71-77 vans were the the same, 78 was one year only on a lot of things, then 79+ were the same. based on the fender marker lights your van is 77. 78's were rectangle and the dash on a 77 is completely different then 78.

Also welcome to the brougham club...i'm alos a member, they went out in the mid 80's. i have had mine for 13 years, this pic was taken last weekend

can't believe it has been 8 years since i have started this thread.....

Looking at his picture and yours I can see your rig is wider than his, that is probably why he has singles and you have duals.

chicknnhead · August 08, 2018, 10:34 AM

True, i wonder what that hub looks like when the wheels off, wonder if it is same rearend only with single wheel installed

Rickf1985 · August 08, 2018, 10:39 AM

It is not, the dual wheel hub is offset far out to accommodate the inner dual.

87Itasca · August 09, 2018, 01:54 PM

Some friends of mine had a '71 Dodge B300 Sportsman with drum brakes all around and 16.5" wheels.

Ultimately, we had to get 16" front wheels off an 80's dodge 250 series 4x4 to work up front. We then had to grind down several areas to fit over the drum, and we then welded and strengthened those areas. Had a local machinist do that work.

The rear tires we used were 16" trailer tires with a 4.77" center hub, IIRC. I switched the lug nuts out to flange nuts, and torqued them all down. It's been two years with no issues. I've checked the studs periodically for any signs of the tires "walking" and have yet to see anything that stands out.

Its a great relief for them knowing, with no spare, if they have a tire issue, they can go to nearly any tire shop, get them to put on a 235-85-16, and keep rolling.

DAVIDMAKAN · September 09, 2022, 06:46 PM

1988 and older Ford 16" coined wheels off of F250 or F350 Van or Truck will fit. Also Dodge 8×6.5 16" will fit also as long as they are coined 1983 and earlier. You can use non coined wheels in the front by centering the wheels with acorn nuts on 3 lugs and tighten the other 3 lugs done, remove acorn nuts with lug nuts then tighten all of them down to 350ft lb.
But there is no way to use non coined wheels in the rear axle. You cannot center the wheels on the hub .

Paul H. · September 17, 2022, 07:30 PM

I have a 1973 Dodge B300 motorhome and I am also trying to convert to 16" rims. I found an article under Google search that states the bolt pattern for my B300 is 8 lugX5.5" bolt pattern. I cannot find these 16", 8X5.5 OEM wheels ANYWHERE and I am wondering if that 5.5" bolt pattern stated in the article is correct. I am desperate search for 16" rims for my Dodge B300.

If anyone has been successful at finding 16" rims for a 1970's Dodge B300, and can direct to the place they got them from, I would be so appreciative. I need new tires and cannot afford a full set 16.5" tires.

Livin' on a budget.

AOBrodie · September 18, 2022, 09:01 PM

If it is a dually it is 8 lugs on 6.5" (not 5.5") bolt circle. I don't know about the singles.