model and tire questions ??

fury4406 · 01-10-2019, 04:02 PM

Hi
New member here and in a quandry...
My wife and I aquired our 5th wheel as part of an inheritance
but many things on it don't make sense to me.
it's titled as a 2002 Cedar Creek 30RKBS (date coded 02-2002) but nothing online shows that model till 2003.
the sticker shows tire size 235/85-16E but it has 225/75-15D on it.
I plan to change the tires and go with 225/75r15E as the tag says it's 5200 lb axles and the Goodyears are 2850lb per rated.
will I have issues with load on these tire/rim combo ??

IsleDog · 01-10-2019, 04:13 PM

Welcome! there are lots of good resources here to answer your questions.

I cannot comment on the date code further than sometimes they title things in a weird way when it comes to RV's. someone else on here will have better info there.

As for your tires, get them swapped! what is on there now (as you have figured out already) is undersized and under rated. lots of us will be curious as to why you would not go with what the sticker has listed for tire size. make sure that the 15 inch rim can handle the increased tire pressure as well.

double check ALL of the tires on that trailer, not just one of them. it has come up before that someone had a trailer (new to them) but the previous owner had 2-3 different size tires AND rims on it!

fury4406 · 01-10-2019, 04:27 PM

thanks for the quick response !!
all 4 and the spare are the same size and D rating
Aluminum rims on the ground and steel spare.
Will check on the rim ratings somehow.
this is our first big RV... we are primarily big boaters
BTW ... I run a auto repair and tire store so I figured the D tires were light

fury4406 · 01-10-2019, 04:31 PM

i see this got moved
sorry for the miscatagorization... been a while since ive done forums

itat · 01-10-2019, 04:46 PM

I agree that models and model years can be a little fluid in the RV industry. My 2011 Rockwood has 2011 colors inside but the model isn't in the 2011 Rockwood brochure I was able to find online. It was manufactured very early in the 2011 production cycle and the model may have been dropped very early in the production year. Who knows.

If the sticker shows the tire size should be 235/85-16E, have you investigated whether that size will fit and whether you should upgrade the rims back to that size? Does the sticker say exactly "235/85-16E"? Would that have been a bias ply tire rather than a radial (which would say "235/85R16"). Maybe a change to radial ST tires gave the same load rating for a 15" tire? Ultimately, as long as the rims and tires are rated for at least as much weight as the axles, it should be OK.

fury4406 · 01-10-2019, 04:53 PM

Quote:

Originally Posted by itat

I agree that models and model years can be a little fluid in the RV industry. My 2011 Rockwood has 2011 colors inside but the model isn't in the 2011 Rockwood brochure I was able to find online. It was manufactured very early in the 2011 production cycle and the model may have been dropped very early in the production year. Who knows.

If the sticker shows the tire size should be 235/85-16E, have you investigated whether that size will fit and whether you should upgrade the rims back to that size? Does the sticker say exactly "235/85-16E"? Would that have been a bias ply tire rather than a radial (which would say "235/85R16"). Maybe a change to radial ST tires gave the same load rating for a 15" tire? Ultimately, as long as the rims and tires are rated for at least as much weight as the axles, it should be OK.

it actually says LT235/85R16/E which is a light truck tire as opposed to a Trailer tire
???
that is also a 32" tall 3000lb rated tire

fury4406 · 01-10-2019, 05:00 PM

and how would one find out the rim rating ?

67L48 · 01-10-2019, 05:08 PM

Don't worry so much about the pressure. E rated tires are good to 80 psi and I've never seen a wheel that isn't rated to at least that much. Wheel pressure ratings are more important when you use tires that are in the 100s of psi. At 80 psi and below (E ratings and below), not a lot to worry about. I'd worry more about general condition of the wheels, rather than some psi rating on them.

BTW, if you want to approximate the overall dimensions of the original tire and keep the 15" wheels, you'd need 235/90-15 or 225/95-15. I don't even know if those sizes exist.

If your budget allows, I'd consider putting ST235/85-16 Goodyear Endurance on, which would require new wheels (obviously). That would restore the original tire dimension in an appropriate ST trailer tire from a reputable brand.

Good luck.

fury4406 · 01-10-2019, 05:15 PM

Quote:

Originally Posted by 67L48

Don't worry so much about the pressure. E rated tires are good to 80 psi and I've never seen a wheel that isn't rated to at least that much. Wheel pressure ratings are more important when you use tires that are in the 100s of psi. At 80 psi and below (E ratings and below), not a lot to worry about. I'd worry more about general condition of the wheels, rather than some psi rating on them.

BTW, if you want to approximate the overall dimensions of the original tire and keep the 15" wheels, you'd need 235/90-15 or 225/95-15. I don't even know if those sizes exist.

Good luck.

I would guess they were changed out to drop it the 2.5" at the step
the D tires are disturbing to me though. It will for sure get E tires.
but why would they designate an LT radial though ??

67L48 · 01-10-2019, 05:29 PM

There's a massive debate over RV tires. Many people swear that LT tires are the best tire for trailers due to better overall manufacturing practices of LT tires (and some other reasons). Others swear that ST tires are specially made for the loads and tracking a trailer sees. I won't try to recreate or even invite the arguments here. Just know that it's polarizing. Think Pepsi/Coke. Ford/Chevy/Dodge. Diesel/Gas. Superman/Batman. Dogs/Cats ... and LT/ST.

Some trailers today have LT tires on them, I believe. My trailers always have had and will always get ST tires.

In your case, probably either would be just fine.

Good luck.

valleyduo · 01-10-2019, 05:30 PM

Were ST tires as common in 2002 as they are now? I worked in a tire manufacturing facility in the 90s and ST tires were not part of any production line there at that point.

hbillsmith · 01-11-2019, 02:40 PM

Quote:

Originally Posted by fury4406

I would guess they were changed out to drop it the 2.5" at the step.

Since it was an inheritance, could it be that for the last few years the trailer was semi-permanent at a full-time or seasonal spot? So without concern for highway safety the focus would have been on the off the ground height and tire expense. So switching to 15" D was cheaper and as said 2 1/2 " lower to the ground.

fury4406 · 01-11-2019, 03:17 PM

Quote:

Originally Posted by hbillsmith

Since it was an inheritance, could it be that for the last few years the trailer was semi-permanent at a full-time or seasonal spot? So without concern for highway safety the focus would have been on the off the ground height and tire expense. So switching to 15" D was cheaper and as said 2 1/2 " lower to the ground.

My father in law bought the trailer from the original selling dealer approx 2 years old. it was an older couple that bought it originally. not sure how it was used prior to his purchase but 1 tire was replaced by him and they just matched what shredded. but GOOD point for a possibility

D W · 01-11-2019, 04:03 PM

The first thing I would do is load that rig up with what you want to haul in it and head to the scales to determine what kind of a "footprint" it has. Then you can make an informed decision of what size tires to run. But from the git go I would say that the current 225/75 - 15D tires will be a tad too light, or marginal with 5200 lb axles.

Alloy wheels normally have max pressure and/or load rating on the inside of the center hub.

DustyRoads · 01-11-2019, 08:19 PM

Quote:

Originally Posted by fury4406

and how would one find out the rim rating ?

Some times the rims will have it stamped on them. My pop-up Trailer rims did. I have not checked my current rims. I will be checking that in the spring as I will be upgrading my tires.
I plan on looking close at the Goodyear Endurance tires.

Airdale · 01-12-2019, 10:17 AM

The correct replacement tire is any LT235/85R16E. That tire has a maximum load capacity of 3042# @ 80 PSI. It's the minimum standard set for that trailer by its manufacturer.

Whoever put tires on there with less load capacity than the original tire provided were using their own safety standards.

In the reference below there is a statement about replacement tires that is a "carbon" copy of what the industry standards are for replacements on all vehicles built under FMVSS standards.

https://www.michelinman.com/US/en/he...res.html#tab-4

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