Forum Discussion
Atlee
Mar 31, 2012Explorer II
CapriRacer wrote:Atlee wrote:
From reading this long thread, I get the idea that many folks want to go to a larger size TT tire because they are on the ragged edge between the weight of their loaded TT and the factory supplied ST tires. There is little margin for error. Is this correct?
Now to my situation. I just bought a used HiLo TT. The GVWR is 5,500#. The GAWR is 3,500# each, totaling 7,000#. The ST205/75R15 LRC Goodyear Marathon tires have a weight rating of 1,820# per tire at 50psi, totaling 7,280#.
Given these numbers, I presume "margin of error" isn't something I need to worry about, WRT the axles and tires. Am I correct?
Interesting side note. They are factory supplied tires. The 2 on the left side are USA Marathons built in 4408. The 2 on the right, plus the spare, are Chinese Marathons built in weeks 08,09, & 10 of 2008.
Let's follow what my web page says:
Barry's Tire Tech - ST Tires
First, it sounds like you haven't weighed your trailer - only quoted what is written on the certification labeled. If that is so.....
Then your 3500# GAWR (1750# per tire)has to be re-evaluated as 2013#. You'll want tires that are loaded to 85% of their rated load = 2013#/0.85 = 2367#.
So, No!, the tires are not according to my recommendations - and it looks like a simple one step up to a Load Range D isn't enough. This looks like a double step to ST225/75R16 Load Range D.
If that's the case, I will forever be using underrated tires. Going to that size tire isn't in the cards.
It also seems like every trailer out there is riding on too small of a tire.
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