Posted 2011-02-18 8:35 AM (#130454) Subject: Trailer tires?
Veteran
Posts: 212
Location: novinger, mo
I need to replace the tires on a horse trailer with a GVWR of 17,000#. Looking at tire specs it doesn't seem to have tires with a high enough load range. 17,000/4 tires would be just over 4000# per tire. Am I figuring this wrong? I have 16" rims on the trailer.
Posted 2011-02-18 8:43 AM (#130455 - in reply to #130454) Subject: RE: Trailer tires?
Veteran
Posts: 188
Location: Ingalls, Ks
Some trailer manufacturers figure gooseneck pin weight into their GVW, some don't. Have no answer as to why. I would recommend Goodyear 614rst tires. They're expensive, but I think they'll pay off in the long run.
Posted 2011-02-18 1:33 PM (#130468 - in reply to #130454) Subject: RE: Trailer tires?
Expert
Posts: 2453
Location: Northern Utah
The Goodyear 614RST are a 14 ply tire and are rated @ 3750 at 110 psi.
These are the best tires out for trailers using 16" wheels.
4 tires = 15000 lbs or load capacity And then you can add in what goes on the gooseneck.So if you trailer is 17,000 and 25% of the total trailer weight is on the Gooseneck pin, 17,000-4250=12,750 on the axles and tires.
Make sure you have wheels & valve stems that are rated for 110 psi.
Posted 2011-02-18 7:09 PM (#130476 - in reply to #130473) Subject: RE: Trailer tires?
Extreme Veteran
Posts: 402
Location: Lockport, Illinois
Originally written by wyndancer on 2011-02-18 5:16 PM
Switch'em over to Kumho 17.5's....you'll never regret it. Around 4600lbs per tire
How about some more information on the tires, what model Kumho tires, what size tire, how much did 4 tires and rims cost, and did they without modifications to the trailer?
Posted 2011-02-19 3:13 PM (#130505 - in reply to #130454) Subject: RE: Trailer tires?
Extreme Veteran
Posts: 406
Location: Minneapolis, MN
Oh, it ain't cheap, but your tires worries are over.
You can save a bit of money by not changing the 1/2" studs to the 5/8" studs. You know bigger studs need bigger lug nuts.
A set of 5 Kumho KRT02, 4800lbs each, 5 new 17.5 rims, 32 studs, 32 lug nuts...mounted, just under $2000.
Depending on your axle, really the hub. They may accept the 5/8" studs. The 17.5 rims are hub centric, whereas the 16" are lug centric...some just leave the 1/2" studs and put the nut on backwards. I guess it would work, but the 5/8" nuts are a flange nut 1 1/16" socket I recall.
A good friend of mine was running the Goodyear 614RST's...they'd pop a couple/year. Now, after 2 years....not a failure.
Posted 2011-02-19 8:30 PM (#130516 - in reply to #130454) Subject: RE: Trailer tires?
Expert
Posts: 3853
Location: Vermont
Most (all?) trailer wheels are lug-centered, not hub-centered, which means it's important that the right nuts be used (with the proper cone angles fit the wheel) and that they center properly, hence the staged torquing.BTW, torque specs vary widely -- I have a Dexter PDF with specs ranging from 75 to 325!! ft-lbs on 4-,5-,6- and 8-bolt wheels. To get to it, go to http://www.dexteraxle.com/products___literature Axle Service Info > 600-8K > Service Manual. There is nothing wrong with this system for lighter loaded axles and on trailers slightly misaligned systems in unoccupied vehicles is not an issue like on passenger carrying vehicles. In true "lug centric" type wheel/rim systems the torquing sequence IMHO is very important and you should pay close attention to the torque specs for each step and the proper torqing sequence on the hub studs to get the wheel centered on the axle as best as can be done.
Posted 2011-02-19 8:52 PM (#130517 - in reply to #130454) Subject: RE: Trailer tires?
Extreme Veteran
Posts: 406
Location: Minneapolis, MN
Paul, as you probably know, the rims on say the 1999 and up Ford Super Duty's SRW are hub centric...they have a flanged nut. And as you probably are aware, the hub centric aluminum rims in the salt belt can be a treat to remove, if you haven't had one off for a while.
On the hub centric rims, the bore that fits the hub fits rather closely, that close fit provides a tolerance of radial runout. Short of using some sort of dial indicator to measure the radial run out, you're not changing it with improper lug torque. The rim/wheel is clamped to the hub. Axial run out could easily be effected by torque and/or debris on the hub face or mating surface of the rim/wheel.