Tire pressure

[PRK]

My tires have 80 psi max inflation rating. Forest a River lists 61 psi on the door jam. Is this 61 psi rating for a CCC that is maxed out? I’m thinking I should be at the higher psi due to the load?

[Whalenss]

The best way to determine correct tire pressure is to weight the unit fully packed, including fuel, then refer to the tire manufacturer's recommendation on weight and tire pressure.

For my unit recommended tire pressure from FR included factoring in CCC. I know this because I have weighted the coach fully packed and refered to tire manufacturer recommendation.

[cfo111]

X2

[Bill Davis]

When I replaced mine with Michelin’s I used their tire pressure chart against my Cat Scale axle weight and my optimum pressure was 55psi.

[dward51]

Tire pressure on the sticker (trailer or your tow vehicle) relates to the capacity of the trailer/vehicle as it left the factory.

If you have changed tires, use the sidewall PSI number to get the maximum carrying capacity. If you run an 80psi tire at 61psi, that tire will not have the full rated capacity that is on the side wall as that capacity is at the full PSI. Same is true for your tow vehicle. Most tire companies have a chart to show the load range capacity de-rating for a lower PSI.

Here is an example from Goodyear.

https://www.goodyearrvtires.com/pdfs/rv_inflation.pdf

Edit ------
I totally missed you have a Isata 5, but the sticker vs tire PSI value info remains the same.

[TowPro]

Sounds like you have the mbs chassis like we do. I run 61 psi

[PRK]

Thanks for your replies. I’ll run at 80psi until I get to the scales then adjust from there.

[milkman55]

I think running them at the max PSI may cause issues due to over inflation. I never could find a load chart from Continental for the OEM tires, but I run mine fully loaded to gross weight and have used 63 PSI the past two years and 16,000 miles. The wear on the tires is even and the ride is acceptable.

[PRK]

Originally Posted by milkman55

I think running them at the max PSI may cause issues due to over inflation. I never could find a load chart from Continental for the OEM tires, but I run mine fully loaded to gross weight and have used 63 PSI the past two years and 16,000 miles. The wear on the tires is even and the ride is acceptable.

Thanks. I have been unsuccessful trying to find the Continental load chart as well.

[Whalenss]

Originally Posted by milkman55

I think running them at the max PSI may cause issues due to over inflation. I never could find a load chart from Continental for the OEM tires, but I run mine fully loaded to gross weight and have used 63 PSI the past two years and 16,000 miles. The wear on the tires is even and the ride is acceptable.

Try this link.

https://www.continental-truck.com/tr...downloadcenter

[milkman55]

I have seen that link before and it only lists one 16” tire size and it’s not the tire used on the Sprinter, close, but not exact. Based on that chart, 65 PSI looks about right.

[chroniekon]

I run mine at 65.

[Barch]

I run 64 psi.

[Dbrote]

I run 65 front and 70 rear. I also seem to be running about 250 lbs over on my MBS 2400R