Montana Owners Club - Keystone Montana 5th Wheel Forum - View Single Post

rickfox · 06-22-2006, 08:42 AM

Good Afternoon All,

We took delivery of our 3400RL in November of last year. It had Mission ST235 tires rather than LT245 tires. And there is a significant difference. As a matter of fact, it says right on the tires that they are for trailer use only.

According to Goodyear, ST tires are made with stronger sidewalls than LT tires. These stronger sidewalls reduce the amount of sway or wag (in part caused by side to side tire flexing) that typically occurs with trailers - this is a good thing for trailers. ST tires typically also come with less tread depth allowing them to run cooler, but as a result you get less total mileage per tire - but who has had to replace at trailer tire because the tread wore off?

However, both of these differences reduces the tire tread's ability to stay on the ground as the tire goes into turns - this is a bad thing if the ST tire is on the steering axle such as on a TV.

Many or the trailer manufacturers are now switching to ST tires and away for the LT's (example is Keystone) now that the ST's are coming in higher load ratings. For example the ST235's coming on the Monty's are rated at 3500# per tire when pressured to 80 psi.

You can now run less pressure - say 75# per tire - and still have plenty of load capacity, the trailer will not ride quite as harshly, and you have a tad better immunity against road hazards.

Running ST tires seems like a pretty good idea for trailers, but not for TV's.

06-22-2006, 08:42 AM	#11
rickfox Montana Master Join Date: Jan 2005 Location: Royse City Posts: 520 M.O.C. #2959	Good Afternoon All, We took delivery of our 3400RL in November of last year. It had Mission ST235 tires rather than LT245 tires. And there is a significant difference. As a matter of fact, it says right on the tires that they are for trailer use only. According to Goodyear, ST tires are made with stronger sidewalls than LT tires. These stronger sidewalls reduce the amount of sway or wag (in part caused by side to side tire flexing) that typically occurs with trailers - this is a good thing for trailers. ST tires typically also come with less tread depth allowing them to run cooler, but as a result you get less total mileage per tire - but who has had to replace at trailer tire because the tread wore off? However, both of these differences reduces the tire tread's ability to stay on the ground as the tire goes into turns - this is a bad thing if the ST tire is on the steering axle such as on a TV. Many or the trailer manufacturers are now switching to ST tires and away for the LT's (example is Keystone) now that the ST's are coming in higher load ratings. For example the ST235's coming on the Monty's are rated at 3500# per tire when pressured to 80 psi. You can now run less pressure - say 75# per tire - and still have plenty of load capacity, the trailer will not ride quite as harshly, and you have a tad better immunity against road hazards. Running ST tires seems like a pretty good idea for trailers, but not for TV's.