tire pressures

[rcwalther]

I own a 2006 NRV Sea Breeze LX 8341 on a Ford F53 chassis with 22.5" Alum wheels. In looking at the label in a cabinet listing tire pressures the label lists 19.5" wheels and 80 psi pressures. Does anyone with a 8341 on a F53 chassis have the label listing the 22.5 wheels/w 235/80R tires and pressures?

Both the Ford manual and the NRV manual do not list tire pressures. They state to check tire pressures but not any pressures. I've since figured I'd go with 80 psi front and 90 psi rear. I had been using 95 psi but the ride was harsh. Because of health issues I've put approx 800 miles on the RV. With health better we are planning to travel more.

Thanks, Richard

[rcwalther]

I own a 2006 NRV Sea Breeze LX 8341 on a Ford F53 chassis with 22.5" Alum wheels. In looking at the label in a cabinet listing tire pressures the label lists 19.5" wheels and 80 psi pressures. Does anyone with a 8341 on a F53 chassis have the label listing the 22.5 wheels/w 235/80R tires and pressures?

Both the Ford manual and the NRV manual do not list tire pressures. They state to check tire pressures but not any pressures. I've since figured I'd go with 80 psi front and 90 psi rear. I had been using 95 psi but the ride was harsh. Because of health issues I've put approx 800 miles on the RV. With health better we are planning to travel more.

Thanks, Richard

[Submustang]

The best way to do it is weigh it loaded for travel, all four corners if possible. You can find a chart on Michelin's website that give inflation according to tire size and weight. Most people use the highest of the two weights on the each axle to determine the tire pressures for the respective axle, so that you have the pressures equal on each axle.

[Fred and Bonnie]

If you don't any answers from Sea Breeze owners, use the axle rating for the weight. This will most likely produce a rough ride, but the tires will not be underinflated.

If you don't have them these are the links for both GoodYear and Michelin inflation charts.

Goodyear

Michelin

Fred

[Tom and Patty]

Richard,

As Fred said, use your gross axle weights. They should be posted in the coach or you could maybe find the capacities in a brochure. Then go to one of the links that Fred posted. You tire size is probably 235/80R22.5? Find your tire size on the chart and follow it over. Gross axle weight, divided by two, will give max PSI for your coach per tire. Of course the rear GAW will be divided by four .

[Richard S.]

rcwalther
I got my motorhome weighed at a moving and storage company. I see in the yellow pages that there are three in your area. Also in your coach you will find a manufactured weight listed on the data sticker. You can add on for water, supplies, LP and passangers and get close to the weight. Other places to look for scales. Highway Patrol, Trash CO. Construction CO, Feed and Grain. The tire pressure listed in the motorhome will be the MAX. most likely 90 PSI
Good Luck

[wallynm]

The best way is to weigh the four corners of the MH and then use the tire manufacturer's pressure charts.

Further discussion.


My Standard CCC Discussion

CCC is defined as the weight of the motor home plus the weight of the engine fluids, fuel, full tank of water, LP gas and four passengers @154 lbs. each (for my DSDP) subtracted from the GVWR (31,000). The sticker in my Motor Home gave me the following information. All weights are in lbs.

Dry Weight 23160
Weight with engine fluids, fuel 700
115 gals of water 958
LP Gas 144
4 passengers@154 each 616

Total Weight 25578

CCC is listed as 5422 or 31000 lb. - 25578 lb.

The sticker further states that any other installed options, dealer installed options, and hitch weight would reduce the CCC.

We run tubeless Michelin XZA1 -275/70R-22.5 LRG on 22.5X8.5 inch wheels with 10 bolt lugs on 11.25 inch diameter bolt centers.

Freightliner specs the tires and wheels @ 120 psi max.

Newmar specs the tires @ 115 psi max.

Michelin specs the tires @ 131 psi max @ 6945 lbs. load max in single configuration and 123 psi max @ 6495 in dual configuration.

I assume the Newmar spec is designed not to exceed the 12,000 lbs. front and the 19,000 rear axle ratings.
9/18/02
Cat scale axle weights

Status of fluids at time of weighing we had a ~1/4 tank of water for ~250 lb., ½ tank of LP for ~ 70 lb., about a ¼ gray and black water for ~ 200 lb.. Of course we were full of fuel and "engine fluids"�. In addition we carry things like a mounted spare, 20 ton jack, three drawer tool chest, normal food items, clothes, ~100 music CD's, bottled water and the bride and I( we average a little more than 154 lb. each). I am assuming that the two extra 6 volt batteries and 2000 watt inverter were included in the dry weight of the motor home.

The axle weights were as follows:

Front axle is rated at 12000 lb. and weighed 9840 lb. So we still have 2160 lb. in reserve.
Rear axle is rated at 19000 lb. and weighed 16700 lb. So we still have 2300 lb. in reserve

Total weight was 26540 lb. reserve was 4460 lb. which means we could travel with full fresh water, more of every thing else and still be within the CCC.

At the time we were towing a Ford Contour on a Demco tow dolly and those axles weighed in at 3580 lb. That probably added ~150 lb. at the hitch. The CGVW was 30120 lbs. or 10880 lbs in reserve.
3/30/04
RVSEF Four corner weights

Status of fluids at time of weighing we had a ~1/2 tank of water for ~500 lb., 1/4 tank of LP for ~ 30 lb., about and ~ 1/2 gray and 1/4 black water for ~300 lbs, and ~7/8 fuel and "engine fluids"�.

The weights were as follows:

Driver side front = 4,800 lbs.
Passenger side front = 5,300
Total front = 10,100 or 1,900 lbs. in reserve with + 500 lbs on the passenger side

Driver side rear = 8,600 lbs.
Passenger side rear = 8,500 lbs.
Total rear 17,100 or 1,900 in reserve with + 100 lbs on the driver side

Total weight = 27,200 or 3,800 in reserve
No tow vehicle was attached.



6/30/04
Cat scale axle weights

The axle weights were as follows:

Front axle rated at 12000 lb. and weighed 10100 lb. So we still have 1900 lb. in reserve.
Rear axle rated at 19000 lb. and weighed 16760 lb. So we still have 2240 lb. in reserve

Total weight was 26860lb. reserve was 4140 lb. which means we could travel with full fresh water, more of every thing else and still be within the CCC.

At the time we were towing a Chevy Suburban that weight 5720 lbs. That probably added ~10 lb. at the hitch. Total GCVW was 32580 lbs with 8420 in reserve

4/8/05
RVSEF Four corner weights

Status of fluids at time of weighing we had a ~1/2 tank of water for ~500 lb., ½ tank of LP for ~ 70 lb., about a ¼ gray and black water for ~ 200 lb. I did not record fuel and "engine fluids"�.

The weights were as follows:

Driver side front = 5300 lbs.
Passenger side front = 4950
Total front = 10,250 or 1,750 lbs. in reserve with + 350 on the driver side

Driver side rear = 8,250 lbs.
Passenger side rear = 9,150 lbs.
Total rear 17,400 or 1,600 in reserve with + 900 on the passenger side

Total weight = 27,650 or 3,350 in reserve

Towing Mustang but no toad weights.



As you can see the weights move around a little from driver to passenger side. The Bride and I were in our seats each time we got the weights. We have generally been fairly stable so based on the Michelin latest inflations table <span class="ev_code_RED">we run 110 psi in the front and 95 in the rear.</span>

[Tom and Patty]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">We run tubeless Michelin XZA1 -275/70R-22.5 LRG on 22.5X8.5 inch wheels with 10 bolt lugs on 11.25 inch diameter bolt centers.

Freightliner specs the tires and wheels @ 120 psi max.

Newmar specs the tires @ 115 psi max.

Michelin specs the tires @ 131 psi max @ 6945 lbs. load max in single configuration and 123 psi max @ 6495 in dual configuration.
</div></BLOCKQUOTE>

Wally if your tires max pressure is 131, your load range designation is more likely LR"J" (18 ply) not LR"G" (14 ply).

You certainly have enough tire under your coach .

[wallynm]

Wally if your tires max pressure is 131, your load range designation is more likely LR"J" (18 ply) not LR"G" (14 ply).


Well I went and checked again and they are LR"H" and are 16 ply. Just goes to show what I thought I knew is not what I know now. THANKS

[Tom and Patty]

Well I was wrong too, "H" is usually 120. I learn something new everyday .

[Fred and Bonnie]

My goodness have we hijacked Richard's original question?

[Tom and Patty]

No, I think we answered it.

1. Weigh or use gross axle specs.

2. Tire load chart of proper size tire.

4. Adjust air pressure.

5. Happy Trails .

[wallynm]

I think we gave him a very specific answer. He needs to weigh his rig and check the manufacturer's inflation tables. Then we made more information available based on the tire specifications as it relates to maximum air pressure. Then we both admitted we learned something new.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Fred and Bonnie:
My goodness have we hijacked Richard's original question? </div></BLOCKQUOTE>

[Fred and Bonnie]

You gave him all the information he cannot use, he is 150 miles from a set of scales.