235/75R15 -> 195/70/R15, any concerns?

[dduffey]

I am thinking to replace my stock Westlake LT235/75R15C "mud rovers" on stock 15x6JJ rims to VANCO 4 SEASON 195 /70 R15 104R D1 BSW CM (on the same stock rims).

I am looking to lower my 2013 Freedom 282TXR and I don't do offroading. I will be highway/paved and RV site camping (not boondocking).

Anyone recommend not going this route?

[pgandw]

I would be very cautious that the weight capacities of the new tires are sufficient.

Are you sure the Westlakes are LT tires (load range C) and not ST tires? Even if the OEM Westlakes are LT tires, it may quite a downgrade going to passenger car tires instead of light truck tires. Again, it's all in the weight capacity, and the max gross weight of your pop-up. You need sufficient reserve weight capacity (at least 10%, preferably 20%), and you have to deduct 10% (I believe) from a passenger tire's capacity in this calculation.

I'm not a tire guy, but if your tire shop is not asking these questions, they are not doing you any favors.

Fred W
2019 Flagstaff T21TBHW A-frame
2008 Hyundai Entourage minivan
camping Colorado and adjacent states one weekend at a time

[dduffey]

Originally Posted by pgandw

Are you sure the Westlakes are LT tires (load range C) and not ST tires?

Thanks, yes they are LT tires load C (picture below). The Continental's would be load "D".

Two maybe valid concerns
1. Tire deformation from sitting?
2. Less side-wall so ride performance differences
3. Wheels operating at a higher RPM and more heat (but the Westlake's are already very high speed rated for a trailer).

David

[pgandw]

Tire deformation from sitting? I don't know that that is any different from an LT to a passenger tire. Reduced side wall height should add stiffness and a slight increase in resistance to sway. Speed rating needs to be greater than the speed at which you are going to tow.

Again, the only concern I would have is any loss of weight capacity. Whatever replacements you use must have the same or more weight carrying capacity to be in compliance with all the tire codes. And passenger tires (I believe) have to be de-rated by 10% when being used on a trailer. But you seem to be avoiding this issue for some reason.

Again, your tire dealer should be going over this with you. I know mine did when I switched tire sizes on my minivan, and switched to LT tires on my Explorer - the dealer made sure I had equal to or greater capacity with the new size.

Fred W

[dduffey]

Originally Posted by pgandw

And passenger tires (I believe) have to be de-rated by 10% when being used on a trailer. But you seem to be avoiding this issue for some reason.

Not ignoring, just ignorant! Thank you Fred, I do appreciate the insights.

I will take a closer look at the Westlake tire ratings and trailer specs and I have setup an appointment to do a professional tire inspection and recommendation this weekend.

Thanks,

David

[Tundra 2014]

I would go to a ST tire the same size and weight rating you have. The Westlakes are the best of the Chinese tires. If going to the trouble to change I would look at the GY or Maxxis.

[pgandw]

Originally Posted by dduffey

Not ignoring, just ignorant! Thank you Fred, I do appreciate the insights.

I will take a closer look at the Westlake tire ratings and trailer specs and I have setup an appointment to do a professional tire inspection and recommendation this weekend.

Thanks,

David

David, thank you. I am simply trying to prevent you from being one of those on the side of the road with damage to their camper from a tire blow out.

Chances are that you will have to stay near the same width (quite possibly at a lower aspect ratio), or go to an ST or an LT D rated tire to get the lowering you want, with the same weight carrying capacity. But I haven't checked weight capacities of the specific sizes you have in mind.

Hope it works out for you.

Fred W

[hobienick]

The tire on a trailer see different loads than the tires on your car or truck. They see more side loads. ST tire have sidewalls designed for this. This is why you are seeing the 10% derating for passenger tires. Maybe stick with ST or LT tires at the smaller size. You can probably get away with passenger tires but they are not designed for trailer applications.

[Tundra 2014]

Goodyear has a diameter chart on their site to help you see the the diameter of the size you are considering, to get the lowering goals you want. I used it the other way, to gain weight rating and still fit in the space I had.

[dduffey]

Thank you everyone for your feedback. Once I have my tire consultation, I will report back what was recommended and specific specs of the trailer.

Originally Posted by pgandw

Chances are that you will have to stay near the same width (quite possibly at a lower aspect ratio),

My TV (stock) runs 255mm wide tires on 241mm (9.5") rims.

My trailer runs (stock) 235mm wide tires on 152 mm (6") rims.

From reading other forum posts they recommend staying withing +/- 10% tire width to rims "in general". This is the case for my TV. In my case of the stock TT tires, they are much wider than the stock rims because of the offroad/mud rovers/tall sidewalls.

It seems like ST tires tend to stick to 70/75% for the sidewall, making it harder to reduce the diameter by just reducing the sidewall without reducing the width as well.

Since 6" rim is ~152mm, a 195mm tire should not be too thin for this rim?

It seems like 185mm is the narrowest common ST sized tire, which should also be sufficient in width for this 6" rim?

Thanks,

[pgandw]

The air inside a tire is what supports the load. You add to load capacity by increasing volume of the tire and/or increasing pressure. Higher pressures require a stronger tire, hence the load range system for LT and ST tires.

By going to a smaller size tire, you will probably need to go up to a Load Range D to get the same or greater load capacity. These are readily available in 15" ST tires. However, ST tires are pretty much limited to the .75 aspect ratio, and have only a few widths for each size diameter. There are very few (if any) LT tires in 15" diameter, LT tires generally start at 16".

hope this helps
Fred W

[dduffey]

Stopped by a few places, and I'm now leaning towards 14x5.5" SENDEL
T-10 wheels with GOODYEAR ENDURANCE ST205 /75 R14 105N D1 BSW tires.

I'm not in a rush, so I'm going to continue to noodle on it.

[pgandw]

Originally Posted by dduffey

Stopped by a few places, and I'm now leaning towards 14x5.5" SENDEL
T-10 wheels with GOODYEAR ENDURANCE ST205 /75 R14 105N D1 BSW tires.

That's the size tire my A-frame uses (LR D). 2040lbs capacity/tire at 65PSI. GVW 3372 lbs with a 3500lb Dexter axle, 10x2.25 hubs/brakes.

Fred W

[NJKris]

Love my Westlakes so far, as other said, not plagued by the problems some other Chinese brands are. They don't give you a huge extra amount of ground clearance, but every bit helps when pulling over ruts, sharp inclines at ends of driveways, etc. Not sure why you want to go smaller.

[dduffey]

My Westlakes "look" good, but they are 2012 tires (original to the trailer), so replacing because it is time not due to brand.

I want to go lower because the trailer sits 2-3" higher than the hitch. I am already at max hitch rise per TV specs.