Spare Tire for trailer

[jrepp44]

My current tires are P215/75R15 on a 15" rim. Is a ST205/75/15 on a 15" rim (that matches the current rim) an acceptable spare?

 

[slowzuki]

Its a better tire than what you are running now if I remember my tire codes.

 

[Diamondpilot]

Running a "P" tire on a trailer is asking for trouble. A "ST" tire is what you really want or many run "LT" tires.

As far as size difference goes a 215 is 27.7" tall and 6.3" wide while a 205 is 27.1" tall and 6.1" wide. The 215 takes 728/revs per mile while the 205 takes 744 revs/mile.

It will be fine as a spare. The real issue is why are you running a "P" tire on a trailer.

Chris

 

[adjusterr]

I suggest you go to Discount Tire, Custom Wheels, Truck & Car Rims | Discount Tire and read the info on trailer tires.
I have been pulling all type trailers for 50 years and learned a lot, it's worth the time. Good luck.

 

[SandburRanch]

Spare Tire - a tire that is often used temporairly to get a vehicle off the roadside to a more secure location until a more permanent solution can be obtained. **** yes use it as a spare. Anything that will roll and touch the ground is better than one that's flat on the bottom side.

 

[Markcuda]

The real issue is why are you running a "P" tire on a trailer

"P" stands for passenger.
If the "P" tire is with in his weight carrying capacity, I see no reason why he can't run it.

 

[Diamondpilot]

"P" stands for passenger.
If the "P" tire is with in his weight carrying capacity, I see no reason why he can't run it.

"P" rated tires do not have the side wall strength to stand up for very long on trailer service. Especially on tandem and triple axle setups. Turning puts tremendous side loads that "ST" tires can withstand.


Chris

 

[JDgreen227]

"P" rated tires do not have the side wall strength to stand up for very long on trailer service. Especially on tandem and triple axle setups. Turning puts tremendous side loads that "ST" tires can withstand.


Chris

Please, the OP did not specify what type of trailer he is using his tires/spare on, lets not cloud the issue by bringing in tandem, triple axles, etc. into the discussion until and unless needed.

 

[TRR]

No, he didn't specify whether he had a single, tandem, or triple axle. However, bringing these into the discussion is appropriate for 2 reasons:
1) We're having to guess his trailer configuration to make the best recommendation. and
2) This forum has consistently provided answers to questions that were not asked, but should have been. (i.e. volunteered information that the OP may not be aware he needs to ask about.)

I appologize if this ruffles anyones feathers, but the above post ruffled mine.

 

[JDgreen227]

No, he didn't specify whether he had a single, tandem, or triple axle. However, bringing these into the discussion is appropriate for 2 reasons:
1) We're having to guess his trailer configuration to make the best recommendation. and
2) This forum has consistently provided answers to questions that were not asked, but should have been. (i.e. volunteered information that the OP may not be aware he needs to ask about.)

I appologize if this ruffles anyones feathers, but the above post ruffled mine.

Your post didn't ruffle my feathers at all, but it's obvious the OP is a newbie, why throw in a lot of information to confuse things at the start?

 

[tulenutn2o]

Also, don't know for sure, but insurance liabilities could come into play with using a tire that is clearly not for trailer use. That said, I have used p series tires on trailers and they do not seem to last, especially with lots of loaded turning. I have never found a p tire to handle properly for trailering, too much flex in sidewall. Stick with LT or trailer specific tires.

 

[Diamondpilot]

My 20 years of experience and 100's of trailers and 1000's of tires tell me "P" tires are waiting for something to happen. I am towing 1000's of mile a year and through that I have learned a thing or two. I am just trying to warn the OP that his trailer really does not have the right tires on it.

Chris

 

[wvpolekat]

My 20 years of experience and 100's of trailers and 1000's of tires tell me "P" tires are waiting for something to happen. I am towing 1000's of mile a year and through that I have learned a thing or two. I am just trying to warn the OP that his trailer really does not have the right tires on it.

Chris

I will second this. At the same time, I have P tires on my trailer because that's what it came with and the budget hasn't allowed updating them.

I do know that many tire shops will not mount P tires on a trailer. Once you say "trailer" they will only do the ST tires.

 

[JDgreen227]

My 20 years of experience and 100's of trailers and 1000's of tires tell me "P" tires are waiting for something to happen. I am towing 1000's of mile a year and through that I have learned a thing or two. I am just trying to warn the OP that his trailer really does not have the right tires on it.

Chris

Have to envy you with that amount of expereince, mine has been only with a 30 foot TT and my current 12 foot utility trailer, Since I never load my utility trailer to anywhere near the 2500 lb maximum cargo weight, my spare tire of choice is one of those compact spares that usually hangs off the bottom of what was formerly an S-10 pickup, found it on the side of the freeway brand new, it has the proper bolt pattern and the load rating and carrying capacity are a great match for my OEM ST tires. Am I doing something dumb or not?

 

[Markcuda]

Also, don't know for sure, but insurance liabilities could come into play with using a tire that is clearly not for trailer use.

There was a thread on here a week or so about using "LT" tires on a trailer.
Tons of peeps said use the "LT" tires, a "LT" tire is not rated for trailers but was still recommended.
How come a "P" tires is not recommended IF the weight limit on the tire is not exceeded?
Plain and simple, a trailer tire would NOT be used on a vehicle, why suggest the other way around then?

 

[JDgreen227]

From the Discount Tire website: Why Use An "ST" Tire

* "ST" tires feature materials and construction to meet the higher load requirements and demands of trailering.
* The polyester cords are bigger than they would be for a comparable "P" or "LT" tire.
* The steel cords have a larger diameter and greater tensile strength to meet the additional load requirements.
* "ST" tire rubber compounds contain more chemicals to resist weather and ozone cracking.

If one uses their trailer often and it is usually heavily loaded, I can understand paying the additional cost of ST versus P and LT tires, the longer service life and additional weather resistance would offset the higher cost. Yet for people like me, who use a lightly loaded single axle utility trailer for a 30 mile roundtrip once or twice a month, it's really hard to justify the cost of ST tires up front.

 

[Qapla]

Another thing to consider is this: "P" tires are intended to be mounted on an axle with shocks that relieve the sidewalls of much of the stress involves with up/down motion of an axle and the load it carries.

Trailers (utility type) usually do NOT have shocks. Therefore, the constant bouncing and stress of the up/down motion of the load is ENTIRELY absorbed by the tire sidewalls. "ST" tires are designed to handle this, "P" tires are not.

As far as the size difference, going from a 215 to a 205 for a spare will work just fine. Greater difference (like using a 175 in place of a 255) would not be a good idea. It will make a single axle load hang low on one side and on multiple axles it will place undue stress on the larger tire as it is carrying most of the load.

 

[Diamondpilot]

Have to envy you with that amount of expereince, mine has been only with a 30 foot TT and my current 12 foot utility trailer, Since I never load my utility trailer to anywhere near the 2500 lb maximum cargo weight, my spare tire of choice is one of those compact spares that usually hangs off the bottom of what was formerly an S-10 pickup, found it on the side of the freeway brand new, it has the proper bolt pattern and the load rating and carrying capacity are a great match for my OEM ST tires. Am I doing something dumb or not?

No problem with that at all. Its a spare. Just to get you off the road and to a repair shop for a proper fix.

Chris

 

[Diamondpilot]

If one uses their trailer often and it is usually heavily loaded, I can understand paying the additional cost of ST versus P and LT tires, the longer service life and additional weather resistance would offset the higher cost. Yet for people like me, who use a lightly loaded single axle utility trailer for a 30 mile roundtrip once or twice a month, it's really hard to justify the cost of ST tires up front.

What size tires does it have and what is the price difference? Say its a 205/75/14, a common size on single axle trailers. I can get them for $66 each. What are you saving going to a "P" tire?

In my area if you pull in with a trailer and want P or LT tires installed they will turn you away or sell you ST tires. They do not want the liability.

Chris

 

[JDgreen227]

What size tires does it have and what is the price difference? Say its a 205/75/14, a common size on single axle trailers. I can get them for $66 each. What are you saving going to a "P" tire?

In my area if you pull in with a trailer and want P or LT tires installed they will turn you away or sell you ST tires. They do not want the liability.

Chris

If I thought a tire shop would refuse to put P or LT tires on my trailer rims, I'd simply take my business elsewhere. Would have to go dig thru three feet of snow right now to learn what my UT tire size is but odds are they 205/75-15's. Would price some LT and ST tires to see what the price difference is if I was interested. Maybe the OP obtained his trailer used with the P tires on it, he has been informed several times here that running P or LT tires on his trailer is unsafe. So far he hasn't given us any feedback.