15" vs 16.5" Tires

[BrowneBlue]

I am thinking it might be easier & cheaper to get some 15" tires for my 1967 D200. Would this be wrong? I would rather go with what was original, but that will be expensive and is hard to find. I like the looks of the Bias-Ply the best. How far off would my speedo be? I can imagine that it is somewhat off with the 16.5 since it originally had 16's. I can't say for sure what ratio my rear axle is, but would it mess with my RPM. This truck has a 318 with 4 SPD. Also, would the radials make the truck handle funny? Thanks,Scott

[steven]

Whats wrong with 16's?

Buy the radials, you wont be sorry

[BrowneBlue]

Nothing at all wrong with the 16's. I just thought it might be cheaper. I was quoted $120 per tire for p235/75r16. A little out of my range.

[wideblock]

for one, a 75 series 16" tire will be more expencive, plus they are wrong for the truck. look for a 225 or 235 85/16. i got mine for $110 each, and they arent the cheapy low dolloar tires. you can usually find house brands at discount for about $80 a piece. the problem with 15"s on a d200 is finding 15" 8 lug wheels. so to change to a 15, youll be out money for the rims as well as tires. and that can get pricey. 16.5 tires are getting hard to find, i paid about $155 each for mine and only had 3 choices in size. its becoming an extinct size.

[BrowneBlue]

Well, I would like to stick with the 6.00x16 size. I'm a 'stock' guy. My parts truck has 12x16.5! Wow!! Would anybody want those? Worth more as scrap?

[soopernaut]

I am thinking it might be easier & cheaper to get some 15" tires for my 1967 D200. How far off would my speedo be? I can imagine that it is somewhat off with the 16.5 since it originally had 16's. I can't say for sure what ratio my rear axle is, but would it mess with my RPM.

The wheel size itself isn't going to change anything. The circumference of the tire would be the cause of any changes. You could run 13s or 20s and have the same overall circumference to the tire and everything would be calibrated correctly. I know you couldn't actually run 13s but it was just an example.
Your speedometer would be off by a ratio not a set amount at every speed. For instance it could be off by 4 mph at 30 and 9 mph at 70. If you run smaller tires it would be lower than what your speedometer reads. Your RPMs would be higher. There is probably an online calculator where you can figure all this out or if you are good at math you can do some calculations.
You can find out for sure what your rear axle ratio is by jacking up the rear. Spin the tire 1 time around and count the number of times the driveshaft makes a revolution. Put a mark on it so you can see when it makes it around. If it is the stock Dana 60 axle it should have a ratio of 3.54 or 4.10. Your door tag would also tell you the ratio if the axle is original.

[BrowneBlue]

Great info soopernaut! Thanks. We live pretty close, I'm in Knoxville. Small world!!

[BrowneBlue]

So....one more thing. How do I know what size of tire goes with what rim? For example.........if I want 6.00X16 tires, then do I look for the same size rim? Or is the rim slightly smaller? I have no idea what I am looking for. Thanks,Scott

[Blue67]

Many tire manufacturers have info on their web site. Example at BF Goodrich here: http://www.bfgoodrichtires.com/catalog/ ... uck/7.html
you pick a tire, click details and then look at 'sizes and specs'. Look at rim size for tire size you want. Also look at 'overall diameter' as diameter will effect the rpm your engine turns

[Johns67]

My 1967 Dodge-D-200 came with split rims. I changed them for 16" regualar rims. Then changed it over to a 4x4. The truck sat to high in the front so I lifted the back to match. It handled terrible so I went to 16.5 rims and ran radials. Later I installed a 1"sway bar on the front and have been happy ever since. 16.5 can be ordered, but like someone said they are not popular, but can be found never the less. Your right on one thing tires can be expensive. I have a second set of 16.5 rims found in a junk yard and got them cheap(no one wanted them -8 hole) Put a set of real agressive thread tires on them with studs on the back for winter snow plowing.
I can give you sizes and tire make, if you'd like them?
johns67 --1967-4x4. One guy said it wasn't a real power wagon-I told him I never said it was.

[soopernaut]

So....one more thing. How do I know what size of tire goes with what rim? For example.........if I want 6.00X16 tires, then do I look for the same size rim? Or is the rim slightly smaller? I have no idea what I am looking for. Thanks,Scott

You would want wider tires than the wheels. I don't know how much wider you can go. If you want tires that are 6 inches wide you would probably want 4-5 inch wide wheels. The aspect ratio(section height to tread width) of the tires also plays a role in how much wider you can go. I'm not an expert on this so maybe you can look it up. In your post you mention a width and a wheel size, but the overall height of the tires can very alot depending on what you are looking for.

You can also go to a tire store and ask them questions.

[wideblock]

good rule of thumb. yes there are variances, its just a basic rule. if you got a 6" rim, dont go smaller then a 5" tire or larger then a 7". now i have put 8's on a 6" rims, but they buldge out a bit, and tend to wear funny.

[nfury8]

I just got 16" steel rims for my 70 to replace the stock 16.5" rims. The problem I see with the 16.5" tires is finding a tall skinny tire. I could pick up 33x12.5R16.5 tires all day long, or even bigger. The Runway 235/85-16 tires I have are going to be PERFECT!

Those 12x16.5 are pretty popular for the big off roaders. There are a lot of 16.5" massive military tires available. The used tire place near me had some 36x12.5R16.5 military monster tires real cheap, those 12" rims would be perfect for those. I would actually like to find a 12" wide set cheap to tuck away for later use.

I was surprised how much used steel rims were going for though. I never found any stock 15" 8 lug wheels, everything was 16". Mine came from an 87 Dodge. $40-$50 was the going price locally. I got lucky and found 2 on Craigs list with tires for $100. The last 2 were $40. So take the the cost of wheels into consideration in your tire cost. They need to be about $40 cheaper to wash even.