Tire psi for 2018 2016 fbs

[JoGlenn]

What is the correct tire psi for the 2018 2106 FBS?

[backtrack15]

There should be a sticker that lists the recommended tire pressures on the street-side up near the front of the trailer. That’s the best source of info if it is still legible.

[creativepart]

I don’t know the direct answer to your question and I’m not sure Travel Trailers have tire inflation stickers... but when I had TTs I was told to run the tires at the max pressure printed on the tire sidewall. For me that was always 80psi, but your tires may be different so you should check.

The cold tire pressure (cold=not having been driven) is all about weight carrying capacity. And that max tire pressure on the sidewall is the max weight carrying number as well.

I looked in your Operators Manul and under tires it says :

TIRES
All tires meet or exceed load and wear specifications for trailers. Proper inflation pressure must be maintained for safe trailer stability and maximum tire life. Load range and maximum cold inflation pressure are stamped on the sidewall. Always inflate the tires to this maximum pressure.

[JoGlenn]

Thanks for your quick reply. However the decal on the outside of TT is blurred
and unreadable. Just wanted to find the original tire info.

[Goodspike]

I'm pretty sure my trailer says 65, and that's the same as the max sidewall pressure on the tire. I try to refill when it gets below 60. It surprises me how long that takes--usually higher pressures mean the tire will lose pressure faster.

[JoGlenn]

Thanks a lot I called Winniebago Towables and they concur. The original specs were
205/75R 14C 6 ply due to the C rating(50 PSI). However they were replaced with
205/75R 14D 8 ply due to the D rating (65 PSI).

Hopefully this will help others with the same question. Once again thanks for the quick responses.

[Sun_Seeker]

Originally Posted by JoGlenn

What is the correct tire psi for the 2018 2106 FBS?

50 PSI

[jadatis]

Best is weighing per axle-end fully loaded as you are going on trip. But in lack of that give GVWR, GAWR's and howmany axles, and the tire-specifications, and I will calclate a highest pressure with stil acceptable comfort and gripp. Comfort for a trailer is that your screws dont tremble loose.
This will be higher then the original advice.
But best for fuelsaving and luvetime of tires.
To be complete, also give the maximum speed you use, and wont go over for even a minute.

[JoGlenn]

3705lbs 7000lbs 2 axles 205/7514D most 65mph.

Thanks

[jadatis]

Then 205/75R14 ST 2040 lbs AT 65 psi upto 65mph
2 axles 3705 lbs GAWR GVWR 7000 LBS.
Then my calc comes to 67 psi , can drop to 56 psi. You must see this as minimum. So keep them on 65 psi.

[jadatis]

When you use a WDH , a bit more weight on the axles of TT, so higher pressure is needed.
And my advice is based on 10% of total weight, so 700 lbs on towbar.
Also no overloading.

[JoGlenn]

Thanks for the info.Hopefully this will help others with the same question.

[backtrack15]

The pre-2021B Micro Minnies are interesting. The 3700# torsion axles are pretty stiff, so a lot of the "give" with the Micro Minnie is from the tires. Normally I'd lean toward D-rated vs C-rated tires, but with the Micro Minnie, the extra stiffness + the increased tire pressure (65 psi) will undoubtedly pummel the trailer more. Thus, I might actually prefer the C-rated tires at 50 psi on a Micro Minnie.

[jadatis]

Because I saw that your OEM tires where C load, I also putted those data in my calculator.
So 1760 lbs AT 50 psi.
Gave 59 psi , can dropp to 49 psi for 65mph.
Then still reserve for unequall load theoretically.
But yust a bit higher speed then 65mph , and/or more weight, and or misreading of pressure, and or etc, and overheating of at least one tire, and then the tire is in fact lost.
It can take a while, but in the end a blowing tire or treath-seperation, and mayby accident.
Then that once overheating is long forgotten, and the cheap Chinese tires are blamed.

That is why you have to go for highest pressure, with acceptable comfort and gripp, so you have reserve for things like that.

For that reason my advice is 67 psi for your D- load, but not allowed anymore, so 65 psi, to please the tiremakers.

This is for cold measured at ambiënt temp of 65 degr F .
If you fill 65 psi at ambiënt temp of 52 degr F , and measure later at 65 degrF, it will give 67 psi.
So my idea is to smuggle that 2 psi, and say you filled 65psi at 52 degrF. Everybody happy, the tiremaker and mother nature, and your TT, because to my conclusions still no bumping as Backtrac15 suspects.

[Tireman9]

Originally Posted by JoGlenn

Thanks for your quick reply. However the decal on the outside of TT is blurred
and unreadable. Just wanted to find the original tire info.

You should be able to get that info and even a replacement sticker from Winnebago. They might need your VIN as the numbers may be model and unit specific because of optional equpment.
Have you looked at the same model on an RV dealer lot?


Are the tires original? If so you can simply inflate to the pressure on the tire sidewall as the DOT required inflation be sufficient to support GAWR and in 2018 RVIA required tires be capable of supporting 110% of the axle GAWR

[Tireman9]

Originally Posted by jadatis

Then 205/75R14 ST 2040 lbs AT 65 psi upto 65mph
2 axles 3705 lbs GAWR GVWR 7000 LBS.
Then my calc comes to 67 psi , can drop to 56 psi. You must see this as minimum. So keep them on 65 psi.

If the GAWR is 3,705 then two tires must be capable of supporting 4,076# (2,038# each assuming perfect weight distribution side to side on each axle) to be RVIA compliant in 2018.


So are you comfortable with a 2# margin?


Have you confirmed tour actual tire loading with scale weight?

[Tireman9]

Originally Posted by jadatis

Because I saw that your OEM tires where C load, I also putted those data in my calculator.
So 1760 lbs AT 50 psi.
Gave 59 psi , can dropp to 49 psi for 65mph.
Then still reserve for unequall load theoretically.
But yust a bit higher speed then 65mph , and/or more weight, and or misreading of pressure, and or etc, and overheating of at least one tire, and then the tire is in fact lost.
It can take a while, but in the end a blowing tire or treath-seperation, and mayby accident.
Then that once overheating is long forgotten, and the cheap Chinese tires are blamed.

That is why you have to go for highest pressure, with acceptable comfort and gripp, so you have reserve for things like that.

For that reason my advice is 67 psi for your D- load, but not allowed anymore, so 65 psi, to please the tiremakers.

This is for cold measured at ambiënt temp of 65 degr F .
If you fill 65 psi at ambiënt temp of 52 degr F , and measure later at 65 degrF, it will give 67 psi.
So my idea is to smuggle that 2 psi, and say you filled 65psi at 52 degrF. Everybody happy, the tiremaker and mother nature, and your TT, because to my conclusions still no bumping as Backtrac15 suspects.

Have to ask why you think it is appropriate to provide incorrect instruction on tire inflation. Why are you ignoring the 110% RVIA regulation?
ST tire load formula is based on a 65 mph max operation speed. Are you saying the formula developed by Goodyear and used by all tire companies making ST type tires are wrong and you know better?
Where does it ever say in any tire technical literature published by any tire company that it is appropriate to under inflate your tires and to depend to tires heating up to raise the tire inflation? That approach is what got Ford in trouble with their Explorer when they specified 26 psi but needed 30.

[backtrack15]

Originally Posted by Tireman9

If the GAWR is 3,705 then two tires must be capable of supporting 4,076# (2,038# each assuming perfect weight distribution side to side on each axle) to be RVIA compliant in 2018...

The new 2021B Micro Minnies use Westlake ST235/75R15 C-rated tires. I can't find info on these tires anywhere online. Reportedly they have a capacity of 2340 lbs/tire at 50 psi along with an L speed rating (75 mph). I guess they should be okay, even on the 4K axles, since they exceed the 110% rule. I had not heard of that rule before.

These tires are used on all 2021B Micro Minnies with a VIN that ends with approximately 52631 or higher.

[jadatis]

Originally Posted by Tireman9

Have to ask why you think it is appropriate to provide incorrect instruction on tire inflation. Why are you ignoring the 110% RVIA regulation?
ST tire load formula is based on a 65 mph max operation speed. Are you saying the formula developed by Goodyear and used by all tire companies making ST type tires are wrong and you know better?
Where does it ever say in any tire technical literature published by any tire company that it is appropriate to under inflate your tires and to depend to tires heating up to raise the tire inflation? That approach is what got Ford in trouble with their Explorer when they specified 26 psi but needed 30.

I dont see what I am doing wrong in this topic.
I advice for the D-load , topic-starter has, 67 psi, and even warn that only 65 psi is allowed.



Because TS gave that OEM tires where C-load, I also calculated for that in same size, and came to 59 psi with all the reserves, and 49 psi is absolute minimum .




That the OEM tires together 2x 1760lbs=3520 lbs , so even negative reserve for the 3705 lbs GAWR per axle, is te responcibility of Winebago.
I think they went from 7000lbs GVWR minus 10% =700lbs on towbarr gives 6300 lbs on the 2 axles = 3150 lbs per axle, and for that the OEM tires are enaugh to the old rules. To my standards ( for what it is worth from this amateur) it should be the GAWR + 10% at least, but for ST even 32 % to take care that my calculated pressure does not come above the "maximum cold pressure" of D-load 65 psi. That is why my calc for C-load comes to 59 psi, while only 50 psi allowed by the tiremakers. I think that topicstarter can draw his own conclusion from this all.

[Tireman9]

Originally Posted by jadatis

When you use a WDH , a bit more weight on the axles of TT, so higher pressure is needed.
And my advice is based on 10% of total weight, so 700 lbs on towbar.
Also no overloading.

This is getting pedantic, but clearly some people do not understand the need to comply with all the applicable safety regulations.



GAWR is not affected by the hitch or pin weight. GAWR should never be exceeded and you can confirm the actual axle weight vs GAWR with a reading on a truck scale.


WDH can transfer some weight from the trailer to the TV but since we check the tire loading in the configuration when fully loaded and hooked up as we would be when driving down the road, I do not see how having or using a WGH can affect the load on the tires as measured on a truck scale.



Tire loading per DOT is not to exceed the GAWR and this assumes a perfect side to side load split which is seen on very few RVs. Most RVs have some side to side unbalance.


If the RV GAWR is 4,000# and the tires are rated for 2,000# at the inflation on the placard inflation they would not meet current RVIA safety requirements. BUT if the tires are rated for 4,400# when inflated to the placard inflation they would meet the Regulations

BUT it would still be possible to have a tire in overload and you can only know this if/when you get individual tire position scale readings which can not be done on most truck Scales.


The tire on the driver side of the RV does not "pick-up" the excess load on the passenger side as there is minimal load transfer side to side. Information from RVIA indicates that over 50% the 10,000+ RVs they have weighed have a tire or axle or both in overload.


This is a major reason for people to have such a high failure rate with their RV tires.