Tires: Tires for 5th Wheel - LT or ST, goodyear wrangler, speed restriction

Question
Barry,

I have a 2003 Alpenlite 32' Fifth Wheel.  I am overdue for new tires as they are the original tires - the 5th wheel was delivered in Aug 2002 as a 2003 model.  I have exceeded the time life of the tires and I just had a blowout as a wakeup call. Fortunately the sidewall blew out but the tire still held 60# so I was able  to get off the road to get it changed.  I am almost religious about running at 80# as Alpenlite recommends.

The placard calls for LT235-85R16 which is what is on the rig. The tires are Goodyear Wrangler.  I am looking into getting tires that are supposed to be for trailers in size ST235-80R16 which is supposed to be for trailers.

I have been reading various blogs on the internet and some of the comments are confusing.  Many people have had problems with the ST tires and from what I gather many of them are from China which may or may not be relevant.  I do prefer to buy US products.

The whole thing is rather confusing.  Many of the 'experts' on the various blogs appear to not know what they are talking about so I just found you website and thought I would give it a go!

The weight on the two axles is about 9800 pounds in traveling mode.

Lee

Answer
Lee,

An ST235/80R16 Load Range E has a load carrying capacity of 3420# at 80 psi, but it is speed restricted to ...... well, I can't seem to find the exact reference, but it is something like 50 mph.

An LT235/85R16 Load Range E has a load carrying capacity of 3042# at 80 psi (single#, but it has a speed restriction indicated by the speed symbol - and typically these are Q speed rated #99 mph#.  But the load capability of a tire is increased as the speed is restricted.  The net effect is that an LT tire with a Q speed rating has more capability #speed vs load) than a comparable ST type tire.

So my recommendation is to stick with an LT type tire.