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Opinions on changing trailer tires...

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Super Trail

5800 mile trip

OK, this is not a brand change, but a change from a "D"-rated ST to an "E"-rated LT. The intent of this thread is NOT to increase the load carrying of the trailer, but to increase the "cushion"... I like overkill on tires. The load I intend to carry this fall would put me at a trailer GVW of around 9,500 pounds.



I have a new 10k GVW trailer... has ST225x75D15s (bias-ply, so they shake pretty good at low speeds even though they are balanced) rated at 2540 pounds per tire. I do not have a spare as of yet, and that will cost me around $150.



I have a bunch of LT245x70R17s (the BFG Rugged Trails) from my truck... rated at 3000 pounds per tire. I researched it a bit and I believe the tires will fit the trailer fine. My trailer "frame" is a 6-inch channel, 14k version but the axles are only 10k... the manufacturer only makes one frame for all their trailers, and the use 235x85R16s on the 14k version. Besides, there is only about 1. 5 inches in height difference between the ST and the LT.



I also researched a rim, a Cragar Soft-8 in a 17x8 with 4. 5 inches of backspacing that I think will work as well... they are rated at 3000 pounds per rim.



Now, by changing from the ST (with a combined rating of 10,160 pounds) to the LT (with a combined rating of 12,000 pounds), I'm gaining just shy of 2k pounds of cushion. The 17 inch rims will cost me slightly more than $200, but I can sell the STs when I get home (I would carry one or two ST as spare) to offset the cost (this will probably be the only long trip they ever take).



Does anyone see any issue with running an LT (rated for a higher load carrying capacity) in place of the ST?? I know guys do this on bigger trailers than this, but I don't know how they hold up.



And again, I'm not trying to sneak more weight onto the trailer than it is rated for, simply trying to give myself a little more cushion...



Thoughts??



steved
 
I have about 20-30K miles on LT tires firstone Transforce HT I believe, tandam axle loaded higher then your planning. I routenly haul at 14 - 15K lbs.



The only issue I have had is nails. Basicly I was told ST = cheaper because they are rate only for trailers, LT= more $$ but readaly avaiable, everywhere.



Only issue I can think of is the meaty lug that you may have. Also the electric brakes may need to be looked at in reagards to the larger diameter for rolling. . IE tire will have more leverage against the brakes trying to stop the trailer. But a simple adjustment on the controller should take care of this





Other wise stop worring and have fun on your trip. Oh and check your lug nuts occasionally, after the change
 
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Yeah, +1 on the switch to LT's. I went from ST15" D load range tires to LT16" tires. The LT's are worlds better, and give great peace of mind.
 
My last camper had E's on it, my new camper has D's. I miss the stiff side wall of the E's when sitting in a campsite. This new camper shakes much more then the old one.
 
My Newmar fifth wheel came from the factory with E rated LT's on it, no problems at all... weighs in at about 14,000lbs.
 
Most the the 5ers I have seen lately on the lot are coming with LTs. I had a Sprinter 29 footer about 2 years ago that had 15sSTs and I converted it to 16s with LTs. I mainly did it to raise the 5er. It did great while I had it. It towed better.
 
Cool, but I had another thought that I will address tomorrow... whether LTs will pass inspection on a trailer... we need anything with brakes inspected in PA...

steved
 
I strongly endorse LT tires on a fifth wheel trailer. Newmar puts only LT tires on their trailers which are heavy; some enough that need a business class truck to tow them legally. My Newmar came from the factory with LT tires. Ran into a fellow at an RV park recently who had all four ST tires go bad on a fifth wheel. Two blew out and two had large bubbles. He may have a trailer that just didn't have enough tire or gotten a bad batch, but that was a lot to go bad. Think his wife was about to abandon the RV lifestyle due to all their tire problems. Lot of ST tires appear to be made overseas in locations that are not known for quality workmanship or materials. I would make the change you are comtemplating.
 
My 22' GN flatbed came with Huanghani YELLOW SEA 235-85-R16 LT YS204 14 plys. Guess they are one of those overseas deals, eh? I actually got about 35K miles out of a set of them on my other flatbed before I had to replace them. They stood up well with 18-20K loads.



CD
 
[snip]

I also researched a rim, a Cragar Soft-8 in a 17x8 with 4. 5 inches of backspacing that I think will work as well... they are rated at 3000 pounds per rim.





Thoughts??



steved

trailer axle bearings require trailer wheels with zero offset. Something to keep in mind when purchasing new wheels for a trailer. Also wide tires on a trailer just adds more side scrub stress to bearings/axles/wheels and even the tire. If you notice the LT from the trailer factory will be 235/85 series for good reason.

Most upper price range and heavy RV trailers come with 16" LT E and G rated tires. Some RV manufactors offer a 16" LT upgrade option. ST tires will be extinct hopefully as we have no more made in the USA ST tires anymore. Firestone/BFG/Delta/Cooper/etchave stopped production over the years as ST tires were a bottom of the pile in tire tech for heavy trailers and interstate speeds. LT s are a great upgrade even in 15" sizes.

JIM
 
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I have been reading this thread with much interest because I have ordered an 08, 27' Arctic Fox 5th wheel, It will be equipped with ST235 85R16 E rated. I have talked to everyone at the factory as well as the dealer on getting it equipped with Michelin XPS Rib 16" LT "E" rated tires. The dealer suggest that I take them to a tire shop and get them changed out. Northwood Mfg says the the ST are better tires and can not install any other tires then what they are under contract for. With all the horror stories I'm reading on the news and the RV Forums on China tires, I just don't want them.
 
trailer axle bearings require trailer wheels with zero offset. Something to keep in mind when purchasing new wheels for a trailer. Also wide tires on a trailer just adds more side scrub stress to bearings/axles/wheels and even the tire. If you notice the LT from the trailer factory will be 235/85 series for good reason.
Most upper price range and heavy RV trailers come with 16" LT E and G rated tires. Some RV manufactors offer a 16" LT upgrade option. ST tires will be extinct hopefully as we have no more made in the USA ST tires anymore. Firestone/BFG/Delta/Cooper/etchave stopped production over the years as ST tires were a bottom of the pile in tire tech for heavy trailers and interstate speeds. LT s are a great upgrade even in 15" sizes.
JIM


As far as the rims... a 4. 5 offset on a 8" wheel shouldn't pose that big a deal... and the 245 I'm using isn't that much wider than the 225s on the trailer or even a 235/16.

I still have to (first, figure out if I'm taking this trailer) figure out if the 8" wheel will fit under the fender... the tire will physically fit the fenderwell, but I can't tell without ordering the rims if they will fit inside the fender lip.

I have never seen an LT-rated 15" tire in a P-metric size... are you referring to the 7. 00-15 and such???

My trailer has "loadmasters" on it... but the thumping concerns me as that can't be good for the tire once it's loaded...

steved
 
I pull a 28' Cardinal w/ 16" wheels. I had two blow outs with the tires that came on the trailer and the tread was like new. When I got the second tire replaced on the road, the tire man said that most people around there were running 7. 50-16 rated at 14 ply with a straight tread. I replaced all four with this tire and haven't had anymore problems.
 
I have a 25' Nash (bumper pull) that came with Goodyear Marathon 205/75/15-C's & I upgraded to Towmaster 225/75/15-D's. The Towmasters are made, in Canada, by Goodyear & are the same (rebadged) as the Marathons.



Fortunately, I've never had any tire problems with either tire. However, with ALL I've heard about trailer tire problems, it's always in the back of my mind whenever I take the trailer out.



Does anyone know of a 15" LT tire that is D or E rated that would fit on my trailer?



The sun, out here in AZ, takes a great toll on rubber. The tires seem to crack (sidewalls & tread) before they actually wear the tread out.



Thanks.



Joe F. (Buffalo)
 
Guys, keep in mind that any st rated tire has a top speed rating of only 65 mph! After having two sets of marathon fail I bit the bullet and put XPS RIBS on after making sure the rims were rated for 80 psi tires. Steel belts and steel sidewalls!
 
I'm still following this thread... I'm glad to see the LT change is widely accepted and well thought of...



One thing to note is that, while I hope no one is towing that fast, LT-rated tires are only speed rated to 74mph unless things have changed... just an FYI for the next time you decide to break the sound barrier with your rig...



I'm still waiting on the guy, whose truck I'm hauling to UT, to determine if he can make the trip or not... I'll slap a set of LTs under it if he's a go, leave as is if he's not. I doubt the trailer will move much more than 100 miles from the house if it doesn't run this trip to UT (the only reason I bought it).



Hopefully in a week or two I'll hear from him...



steved
 
I too have been watching this thread closely, see post #13. Does anyone have any thoughts on how to go about getting brand new 16", load range "E", ST tires changed out to Michelin XPS Rib, 16" range "E". The dealer won't do it and the manufacture won't do it.

I, like georgej, believe this is the best tire for the 5er.
 
I assume your talking about the trailer manufacture and dealer for the trailer... your pretty much in a rock and a hard place. Any tire dealer will install the tires with no issues, If your still in pre perchase I would say look do you want to sell a trailer or not, if you do. Go to a tire dealer and pick up X rims and X tires and install them for me and give me Y amount of credit for your tires. Now go and order the next X amount of trailers with no spare and use my extra tires for spares... . or I'll go some place else..... the thing you have to remember ST tires are really cheap, like 50-75 each, rim is about 25-40$$ ask them how much a spare is, $150 for my ST E tires, so theres not a lot of $$ for tires on your trailer, so they have something round and cheap that works. your local dealer unless he is a dumb idiot should be willing to work with you on getting the tires you want installed. basicly there just stalling hoping you will just take the No as answer and buy the trailer.



Word of advice, I would ask a repepatal tire dealer what he would install, for size, brand ETC. Let his profesional opion be the direction of brand and such. Not someone on this board, or the dealer. Take our advice for towing opioions but unless we have the exact setup as you were only guessing. Also knowing the trailer weight would really help the tire dealer. and knowing how much the total will be.

Also as an FYI there are G and H rated tires and 17 rims that are really high in rating too if your looking for over kill.



But as a review.



Find a tire you are comfortable with.

Have the dealer give you a credit for your tires and get the ones you want.

hook up and drive and have fun. :)
 
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