high5
Michigan
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It's tire time and I need to decide whether to stay with the 8R's or go with the new 225/70Rx19.5's. I know they're slightly smaller diameter but this seems to be a non-issue according to Goodyear. The Goodyear G647's appear to be within my budget and come in both flavors. Is anyone running the 225's on a P30 with stock 6" rims? Thanks.
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Jim83Itasca
La Quinta Calif
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Joined: 09/16/2003
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Yep, I've had them on for a few years.....
With the smaller diameter (1") the slightly different gear ratio helps on the big hills...
Jim
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high5
Michigan
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Thanks, Jim. Did you notice any difference in handling, performance, or gas mileage? What size is your rig?
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Sully2
Cincinnati
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Joined: 01/20/2003
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high5 wrote:It's tire time and I need to decide whether to stay with the 8R's or go with the new 225/70Rx19.5's. I know they're slightly smaller diameter but this seems to be a non-issue according to Goodyear. The Goodyear G647's appear to be within my budget and come in both flavors. Is anyone running the 225's on a P30 with stock 6" rims? Thanks.
I ran Bridgestones on my Southwind. Worked just fine
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UltraKen
Ohio
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high5 wrote:Thanks, Jim. Did you notice any difference in handling, performance, or gas mileage? What size is your rig?
If the tire diameter is different (Revolutions per mile) then the apparent MPG will change. A smaller diameter tire will turn more revolutions per mile than the previous tire. The odometer will record more miles traveled.
When you calculate MPG it will LOOK like your MPG increased.
UltraKen
Ex - 1968 Ultra Van
NOW - 1996 Safari Sahara 35' - Model 3530 - Cat 300
Pictures of my Coach
A $93 Rear Camera System
My take on replacing tires
Used MH Checklist
Toad: Dodge Grand Caravan on Tow Dolly or 1981 Vespa on utility trailer
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Jim83Itasca
La Quinta Calif
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high5 wrote:Thanks, Jim. Did you notice any difference in handling, performance, or gas mileage? What size is your rig?
Handling has always been good and the slightly wider tires grip very nice in heavy rains.
Didn't know it at the time but the 8r 19.5 tires were 4 MPH over (Driving 60 was actually 64) now with the 225-70s 60 MPH is a true 61 with 2 gps units.....
Fuel consumption has stayed about the same (8.0 to 9.25) depending on the winds which can be ferocious crossing any of the desert interstates....
My rig is a (83 454) 33 footer with a Chebby HHR toad (09) which is sorta heavy at 3120 pounds with a full tank (16 gallons).
Performance up the hills with the slightly smaller tires is a NO DOWN SHIFT affiar at 60 MPH with the cruise control on...
Jim
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high5
Michigan
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Well, there doesn't seems to be any reason not to go with the 225's. Goodyear states the diameter will only cause a 2.5% speed error. So, at 60 the speedo would indicate 61.5 mph (if my math is correct). It's interesting though that hill climbing improved significantly with a half inch change in radius.
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Gale Hawkins
Murray, KY
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I think I will go there too. It would be nice for the torque converter to stay locked up longer.
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RV-1/2n-FUN
FL.
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Joined: 03/30/2003
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I went to G670-225 up front 2 years ago. Handling on the P30 was never bad like soooo many have claimed but the 225's made it even better. Left the 8R's on the rear and just put a little more air in the front bags to bring up the front. I know many have mentioned that changing the pressure in the bags with cause problems but so far not a hint of anything happening.
I am glad I went to them.
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high5
Michigan
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RV-1/2n-FUN wrote:I went to G670-225 up front 2 years ago. Handling on the P30 was never bad like soooo many have claimed but the 225's made it even better. Left the 8R's on the rear and just put a little more air in the front bags to bring up the front. I know many have mentioned that changing the pressure in the bags with cause problems but so far not a hint of anything happening.
I am glad I went to them.
Was there a very noticeable height difference between front and rear? According to the tire specs, the loaded height should lower the axle by only half an inch. I installed custom front springs so I don't have air bags to play with.
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