artwin wrote:
Hello out there!
My wife and I just bought a 1976 Dodge based Class C Empire. I believe it is the B300 series on June 10th. 1 Ton chassis with Full floating rear axles. It has a 360, needs new exhaust, tires,brakes are not quite right, big cleaning, the roof a.c. does not work, nor does the cab a.c.
Just found out the fridge may not be working. Although we may be doing something wrong with setting the controls. We'll find out.
I have 1 question about tires:
It has 16.5 inch wheels, with 8.00X16.5 radials. After stopping by a few tire stores, it seems that while those tires are available, they are not as readily available as are the P metric or LT metric series with another rim size such as 16 inch. Has anyone changed over there old dodge to the 16 inch wheels or other size, and if so, what size tires did you go with? I'm concerned about the duals rubbing in the back if I go with something too wide. The 8 inch tires would translate into just under a 205 MM width metric tire.
Thanks in advance and let's all enjoy the summer RVing! We hope to here, we'll need to after working on it !
Art in N.C.
May I suggest you pose your question to Goodyear at www.goodyear.com. My 1970 Explorer class A (1969 Dodge M300 chassis) has H78-16LT tires on it. The tires also have "Replaces 7.00-16LT" on the sidewall. Goodyear said LT215/85R16 is an appropriate replacement.
I posed my question to several tire manufacturers plus the Tire Rack. All except Goodyear either didn't respond or responded with a glorified shoulder shrug.
Converting older system tire sizes is tricky and I'm verifying Goodyear's answer before buying new tires. (I may even buy new rims to get rid of the existing split rims and make sure everything fits.)
I will not make any recommendations as I am still digesting a lot of technical info on tire sizes. I do know that finding the right tire is more than simply finding a tire that will fit the rim.
Staying with tires that are the same diameter is important to maintaining speedometer readings. If you change tire diameters, you will need to change speedometer gears to keep your speedometer accurate. In my case, the old tires are 29.5" in diameter and are correct for the 36 tooth gear I have. The LT215/85R16 tires that Goodyear recommended are 30.5" in diameter and I'd have to change to a 35 tooth speedometer gear to maintain accuracy. (The formula to figure the correct number of teeth is not complex but does require that you know your rear axle ratio.)
In your case and mine, the fact that we have duals raises an additional concern. With dual tires, the tire's section width compared to the rim's setback becomes an issue. If the tire's section width is too big, the duals may rub against each other and tear themselves apart at the sidewall. Even if they don't rub, they may be close enough to allow road debris to become trapped between them.
I know this raises more concerns than helps but it's worth knowing ahead of time. Good luck.
