16.5" rims on my motorhome

I have a 1973 GMC motorhome- the one with the 455 olds engine and front wheel drive. It’s time for me to buy new tires and that means 7 of them. My rims are original, and that means 16.5 inch rims. So I have a couple of options and I’m not sure what is best. A lot of people with these RVs buy 16" rims. They look nice, they’re alloy, and their expensive. Option 1: 7 tires and 7 rims and a credit card bill that will take me months to pay off. Or, Option 2: buy 7 new 16.5" tires and put off the purchase of new rims for 5 or 6 more years hoping I can fill a piggy bank during that period. Local tire shops say they can get the 16.5s in in just a couple days from their distributor. Cost for the two different sizes is about the same, $240 each when all is said and done. 16.5 is just as good as 16, right, just a different size? Do I have to worry that they will put tires on my vehicle that have been in a warehouse for 3 or 4 years and aren’t “fresh”? It’s not as though I drive this thing every day, just 1 or 2 thousand miles a year. Closer to one thousand. Are there any strong arguments for spending the money now instead of later? Thanks.

I’d be fine with 16.5" tires IF they’re less than a year old. They should be able to find that out, and you can check the DOT number before you put them on. They’re the same brand/model/type as the 16"? Radial?

Ask for and interpret the mfg. date codes on each tire before you buy. I’d try to get tires less than a year old. Tires warehoused in a northern location would be a plus. It might be better to simply ask where the tires are stocked but not reveal your thinking. You can help later with tire covers to keep them out of direct sunlight while the motorhome is in storage. We kept our first set of MH tires to 10 years plus unknown initial age, probably at least a year, without incident; located in the upper midwest with a few months total in FL during winter.

Ours had 16.5" tires as well; no problem with that.

I vote for the 16.5s,no problem with them,we used them for years on the company trucks-Kevin(put beauty rings and baby moons on it-if they will work)

Every delivery truck in the U.S. (UPS?) had 16.5 for years, right? Tread’s not gonna wear out, it’s always the rot/age with tires on a motorhome. Two tire places I spoke with wanted me to pay first, and told me they couldn’t get the DOT coding on the tires before they arrived at the shop. If the tires arrive and they’re 3 years old, I’m SOL. The tires I have on the RV now have lasted almost 8+ years though. Load range E. And you should see the spare - it looks like some kind of dinosaur thing. Guess the RV has gone 40 years without a flat. It feels like a stone when I press it. So my concern becomes, are the tires bought frequently enough that the stock turns and the date of manufacture will be recent? If I use my credit card to order the tires, and when they arrive at the shop they turn out to be old, maybe I can have my credit card company reverse the payment? Another thing beyond my understanding, is people talk about the rims “are not made for the radials that are made now.” Huh? How different can the rims be? And the crucial thing - I don’t want to find myself spending a vacation at a truck stop waiting for a repair.

It is reasonable for you and completely within your interest to not want to buy old tires. Shop around for people who will work with you or offer a contract to buy only if the tires are less than a year old. You might offer a bonus of 10 bucks per tire for the unusual request. Ask if they will reduce the price 10 bucks per tire for every year older than one. It is obvious that the tires will need to be discarded sooner at the far end of age if they are old to begin with. We can send a man to the moon and it should be possible to get tire mfg dates in advance of shipping. Possibly an internet tire seller will work with you. I relish a challenge such as yours to overcome stubborn and lazy people.

I’d call tirerack.com, they should be able to help. What is the exact tire size?

I would find a dealer sitting on some 3 or 4 year old 16.5 tires and make him an offer at about half the list price of the tires…Are the 16.5’s radials? Most of them were not, they only come in 3 sizes, with a 6, 8, or 10 ply rating (C, D, or E)…They are not as age sensitive as some of the 3 ply radial car tires…

Here’s some good info from a GMC motor home web site:

8.75R16.5LT - The original tires for the GMC had nylon cord side walls (rag walls) on 16.5 inch hub centered wheels. The little advisory on the glove compartment door says use “D” tires and inflate to 65 PSI which is the maximum for Load Rated D (LRD) tires. “I found where a later GM bulletin suggested going to E rated tires. I had missed that and have been blissfully riding around on D rated tires inflated to 65 psi without any problems. Next time I’ll buy E rated. Justin”

LT225/75R16 - The new direction is to use16 inch wheels made by Alcoa and others. The Alcoa wheels are hub centered and the others are not. The tire that is almost the same size as the original tire ( you will not have to change your speedometer, see options below) is the 225/75R16. You can get these in the LRD or the LRE as shown below.
Many GMCers use LRE tires running at 65 lb and : “The reason for this is the steel chord or polyester chord is heavier gage and will withstand a greater shock like running off the road or hitting a pot hole or a road hazard. Your interpretation is correct, the difference is maximum air pressure allowed”.

I just checked, tirerack only stocks one 8.75R16.5LT make/model, so it might be hard to find new ones.