Chevy class A P30 tires

PA85 · January 07, 2014, 02:41 PM

What is the correct compatible tire size to a 7.50x16? I would like to go with radial that will not rub at the duals in the rear. 1985 Pace arrow 27'

tiinytina · January 07, 2014, 06:26 PM

P30 1980 era 454 class A are usually a 19.5 tire... so not sure if the PO may have changed rims on yours or what. maybe I'm missing something....
Tina

ClydesdaleKevin · January 07, 2014, 07:38 PM

Yep, should be 8R19.5s.

Kev

DonD · January 07, 2014, 07:47 PM

Mine came with 7.50/16 but now has 235/85R16. 1987 Southwind 28ft Class A.

bluebird · January 07, 2014, 08:05 PM

I think my 80 Itasca had 235R16 tires on it, and it was 26 ft. Your tire shop should be able to help you out. I know I also had to buy special valve stems because the wheels were made for tubes and the holes were not round. I had a tube failure and couldn't find one on the road. When I got home I had all the tubes removed and bought the special stems for tubeless. Just another thing to remember, if your tires are over 7 years old, a truck stop won't put them on for you. I found out the hard way.

PA85 · January 08, 2014, 10:03 AM

This one originally came with 7.50/16. Don D do you have any rubbing issues at the rear duals with the 285/75R16?
Thank you all for your help.

DonD · January 08, 2014, 10:40 AM

My memory is flawed. I have 235/85/16's on our rig. Sorry about that.

We have Telstars= 3042lbs@80 2778lbs@80 dual.

I KNOW there was an 85 somewhere.

Funny, at 68 y/o my memory is not as good as when I was 20

PA85 · January 08, 2014, 03:13 PM

No problem. I was wondering how you got those to work with duals

. So i think i will go with the 235/75/16

DonD · January 08, 2014, 04:34 PM

That going to give you enough weight capacity? 2100# single?

legomybago · January 08, 2014, 05:10 PM

We have 245/75-16 on our 1986 26' P30. Plenty of clearance between the duals...

PA85 · January 08, 2014, 06:32 PM

You think the 245's would be a better choice?

DonD · January 08, 2014, 07:20 PM

I would check for weight capacity. Mine give over 6,000 for the front axle.

JDxeper · January 08, 2014, 08:39 PM

You need to watch the section width to allow room for the flex on the radials on the duals. a 7.50 x 16 is not a wide tire. Charts on tirerack.com can give you some insight for comparison. also the overall diameter will determine if your speedometer is close to accurate. The separation of the duals also depend on the off set of the rim also. Just a few more factors to consider when choosing tires

legomybago · January 09, 2014, 10:30 AM

245 would have a slightly larger (wider) foot print...I think that would be the only advantage. Which is a good thing, but you would be fine with the 235's too. They need to be 10 ply tires, load range "E" I believe.....Have the tire store mount some up and take a look at the differance's, they will do that, they want to sell you some tires!!

PA85 · January 10, 2014, 01:33 PM

Now I'm confused

! Went to Discount to put new tires on the Pace, talked it over with the manager (about duals rubbing) and he says : the original Oem tire in a radial compared to 7.50x16 is a 215/85/r16

. So i waited and did some searching (which was confusing). P30 manuals does say 215/85/16 but some people say it hurts gas mileage, the engine rpms will be higher and the speedo will be off. So what do you guys think about that!? Hm?

legomybago · January 10, 2014, 03:14 PM

We checked our speedo manually and with the GPS. We were within a mile per hour on our speedo, and we run 75 series tires. So I imagine 85 series would throw off our speedo...

JDxeper · January 10, 2014, 03:14 PM

Data 7.5 X 16 215/85R16
section width 8.2 inches 8.1 inches
Overall diameter 32 inches 30.6 inches
Tread width 5.5 inches 6.6 inches

The section width determines the space between the duals. About the same no big deal.
Overall diameter will affect the speedometer. According to my calculation the speedometer will be off by 2 percent. 32 -30.6 + 1.4 inches 1.4/32 = .02 or 2%. Probably not a big deal in my opinion.
The requirement for higher rpms should correspond the the speedometer variance. Others please comment if my logic or data is wrong.
At 50 mph you should be off by 1 mph. or 2%
I went through this whole deal when I changed from 17.5 in rims to 16s.

legomybago · January 10, 2014, 03:16 PM

Thats a heck of a lot more than my logic!!!

JDxeper · January 10, 2014, 03:44 PM

I would ask the tire guy if 235/85/16 would work. That's what I have on my 78 Winne dodge. The section width is 9.3 inches and overall diameter in 31.8 inches. The question is the distance between the duals. I have room between my duals but your rims may have a different off set.

My tire guy mounted two tires and we bolted them together to prove to me that there was sufficient space between duals.
I think my tires are load range E

bluebird · January 10, 2014, 08:20 PM

Quote from: DonD on January 08, 2014, 07:20 PM
I would check for weight capacity. Mine give over 6,000 for the front axle.

I agree. I wanted to go up 1 size when I ruined 1 because of the tube. The next size up didn't have the weight rating the 235s did. I know it doesn't make any sense, but that's what he told me, so I stayed with the 235s. My coach had very good tires on it when I bought it, except the spare was very old. I had a tube failure 60 miles from home, and had to really beg them at the truck stop to put on my spare. I didn't have a jack large enough to raise the rear of the coach, loaded with fuel and water. I DO now. I had to sign a waiver before they would put on my spare. Pay close attention to the weight rating on any tire you purchase.