tire inflation recommendations

pianotuna wrote:
Hi Capri,

Yes, I definitely was exceeding the capacity especially on the driver's rear, with the OEM tires.

Yes, the vehicle placard says 65 front and 80 rear.

Someone suggested in another thread that the inner duals might be put at 2 pounds lower--i.e. 80-78-78-80. Is this a good idea?

I will move the generator as far to the passenger's side as I can.

CapriRacer wrote:
Wow, you certainly were overloaded before.

Based on what you have posted, I think you need to use 80 psi in the rear and 65 psi in the front. If I remember correctly, that was what the vehicle tire placard said for the smaller tire - correct?

If your generator is placed behind the rear-axle it yust gives less weight on the passenger front side, strange but true.
So this only would have effect ,if generator is between the axles placed.

But if with your old tires there was overloading, then for the GAWR rear there is still overloading, not for the tires anymore. The old tires must support the GAWR bij law so GAWR rear is below or less then 4 times maximum load of old tires.
But also overloading axles is forbidden by law.
I dont mind but if you are weighed, and it proved to be over 10% you would have to unload in Holland and get a penalty.
Chanche on that is practically zero I know ,but also the technical maximum axle weight rear gets overloaded at a sertain weight, and then laws of nature punisch with unintended camber angle wich needs even higher pressure.

EDIT: Filling this in my spreadsheet I discover a little failure , it gives the reserve weight with 10 digits behind the point , have to round it , but not a real problem.
But if you can procuce the GAWR's the picture gets more complete.
You are around the GVWR so with passenger and some more load yust a little overloaded, but your GAWR rear probably overloaded, wich is also forbidden.

already answered about the genearator in this crossing post.

Hi jadatis,

I am afraid I can't seem to download the spreadsheet. Sorry to be so dense.

Gross Vehicle weight is 14500 lbs.

I am currently running 80 rear, and 65 front (as per vehicle sticker). I believe that 80 is the maximum rating on the metal wheels.

Do you think I should move the generator as far to the passenger's side as I can?

pianotuna wrote:
Hi Jadatis,

Your post is too complex for me to understand. The Toyo tires do have the same rating as the Michelin and Goodyear tires (3042/2778).

jadatis wrote:
Filled only the loads, into my MotorhomeRVtirepressurecalculator and here a picture of it, and chanched it already because I saw the tires in a next post. Looked in a list of Goodyear to find 3042/2778lbs as maxload and 80 psi for E-load. Toyo would not load, but is 99% sertain same loads.

That is because I first made the post without the tire-data, and later chached it because I found them in your later post.
This makes the sentenses sowewhat confusing I realise.
But now you convermed the tire data You can yust read the picture.
But search for the GAWR's and GVWR, and fill them in in the spreadsheet , and it gives more info.

Or is it that you dont understand the other things.
Then only remember the advices of 55psi front and 86 psi rear and dont mind that rear is 6psi higher then AT pressure of 80 psi, 10psi over that is allowed by TRA.

But you weighed without co-driver and other persons in it
passenger side gets heaviër when co-driver is in it, so gives less worse and also weightdivision Front/Back gets a bit better.

Hi Jadatis,

Your post is too complex for me to understand. The Toyo tires do have the same rating as the Michelin and Goodyear tires (3042/2778).

jadatis wrote:
Filled only the loads, into my MotorhomeRVtirepressurecalculator and here a picture of it, and chanched it already because I saw the tires in a next post. Looked in a list of Goodyear to find 3042/2778lbs as maxload and 80 psi for E-load. Toyo would not load, but is 99% sertain same loads.

Hi Capri,

Yes, I definitely was exceeding the capacity especially on the driver's rear, with the OEM tires.

Yes, the vehicle placard says 65 front and 80 rear.

Someone suggested in another thread that the inner duals might be put at 2 pounds lower--i.e. 80-78-78-80. Is this a good idea?

I will move the generator as far to the passenger's side as I can.

CapriRacer wrote:
Wow, you certainly were overloaded before.

Based on what you have posted, I think you need to use 80 psi in the rear and 65 psi in the front. If I remember correctly, that was what the vehicle tire placard said for the smaller tire - correct?

pianotuna wrote:
Hi,

The RV was loaded (water tanks full), but only one passenger (me). There is little I can do to move weight to the passenger's side, unfortunately. The propane tank is on the passengers side. No other heavy items are on that side, and storage compartments are minimal on that side.

The Tires are 235/85R16 Toyo load rating E. Before I had 225/75R16 so I'm pretty certain I was overloaded.

Wow, you certainly were overloaded before.

Based on what you have posted, I think you need to use 80 psi in the rear and 65 psi in the front. If I remember correctly, that was what the vehicle tire placard said for the smaller tire - correct?

Some more conclusions.

If you see the L% ( is loadpercentage, what real load is of weight you calculate the pressure for) rigt front is 81% so a bit low, wich mostly gives discomfort by bouncing ( determined border by myself so discussable 85%). This is done in the spreadsheet to get a L% of 95% on the other side. At the bottom you can chanche these borders if you decide for instance 100% is save enaugh, but I dont advice it.

If you also give the GAWR's and GVWR the spreadsheet also gives warning about overloading.
So if you have Excel or Open Office Calc on your computer, you can download the spreadsheet by RIGHTCLICKING and choose download from the dropdown box. Its xls so to work with down to Excell 97.
Then you can give the GAWR's and GVWR, but also play with the percentages or use in part 2 the whatif load is more at + or less at -.

Filled only the loads, into my MotorhomeRVtirepressurecalculator and here a picture of it, and chanched it already because I saw the tires in a next post. Looked in a list of Goodyear to find 3042/2778lbs as maxload and 80 psi for E-load. Toyo would not load, but is 99% sertain same loads.



Assumed twinwheelaxle,because otherwise the back tires together could not bare the axleload
From this we can draw some conclusions.
Your front 4 point weighig is a little different from the axle weighing.
Probably its becouse of measuring difference of the device it was done with.

Front is a good 25% of total vehicle weight wich is a bit low.
Adviced is to keep that above 30%, for better handling of the car.

In my spreadsheet I use a extra save calculation, and a reserve of 10% standard, and then I wil come to 86 psi advice rear, wich is higher then the maxloadpressure, pressure needed for the maximum load, reference-pressure, but this is not the maximum pressure of the tire.
TRA even allows 10psi extra above this pressure ( yours 80 psi) for better handling and more load at verry low speed.
Your valves can handle it too, because they ar most likely metal valves.

I also placed the spreadsheet under the name pianofulladvice in the examples map of my motorhomeRVcalculatormap on my skydrive.
The examples map with spreadsheet/pdf/gif-image used here under the name pianofulladvice

Your weights are balanced enough to use one pressure for all the tires. There are very few RV's (or other trailers and trucks, for that matter) that are perfectly balanced. IMO, using one pressure for radial tires improves the handling. Adding more to the rear tires never improved longevity or handling in my experience.

With new "E" rated tires, I'd go right to 80 lbs. and see how the ride is. If it's too stiff, let some air out in small increments.

Hi,

I do have a Yamaha 3000 iSEB generator which is more or less centered on the rack (in the receiver) at the rear. If I moved that as far as I can to the passengers side would that shift weight to that side somewhat? It does weigh in at 186 lbs (wet).