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Old 08-09-2018, 01:31 PM   #1
Javi
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Tires 3420, wheels 3200, axles 5200 & GVWR 12,300

What a CLUSTER..
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Old 08-09-2018, 02:38 PM   #2
sourdough
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I'm guessing that's your trailer?

Looks like you fell into kind of the slot I did. When I pulled the specs for your trailer (I'm assuming that's the topic) they list the gvw as 12,090, dry weight as 10,330 and tongue of 1760. They pulled that 1760 off the gvw which left them with 10330 and gave you 5200 lb. axles (10,400) to give you that extra "fluff margin". They really went overboard on the tires and wheels; not sure what they were doing putting higher rated tires on the wheels but at least they were trying to give you even MORE margin. Of course, I know you already knew that. They can definitely make you shake your head....
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Old 08-09-2018, 02:40 PM   #3
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GVWR is actually 12,350 by the sticker...
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Old 08-09-2018, 02:45 PM   #4
sourdough
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Looks like they were just picking out of the wrong parts bin or couldn't read or??? - you should have had bigger axles IMO.
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Old 08-09-2018, 05:50 PM   #5
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I don't see anything wrong with your numbers. If you deduct 1950# for tongue weight from the GVWR you get two 5200# axles. You would have to overload your axles for the tires to overload the wheels.

Everything meets minimum building standards.
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Old 08-09-2018, 06:00 PM   #6
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Yep, same here put a good set of LT tires on it and don’t worry about tires for about six years!
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Old 08-09-2018, 06:50 PM   #7
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Originally Posted by CWtheMan View Post
I don't see anything wrong with your numbers. If you deduct 1950# for tongue weight from the GVWR you get two 5200# axles. You would have to overload your axles for the tires to overload the wheels.

Everything meets minimum building standards.

1950 tongue weight? Explain.....
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Old 08-09-2018, 07:45 PM   #8
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1950 tongue weight? Explain.....
12,350 - 10,400 = 1,950
Not likely that at full GVWR the pin weight would only be 1,950# as that is only about 16% would need to be 20% to 25%, 2,470# to 3,088#.
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Old 08-10-2018, 01:38 AM   #9
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I don't see anything wrong with your numbers. If you deduct 1950# for tongue weight from the GVWR you get two 5200# axles. You would have to overload your axles for the tires to overload the wheels.

Everything meets minimum building standards.
Never said it didn't... still, as someone who makes his living designing mechanical things... not how I'd want to do it...

Actual pin weight is closer to 2900 than 1900 because everything that holds weight in this trailer is in front of the axles.. only the fresh water tank is behind..

Like said above... don't need 3420 tires... since the wheels are only 3200... and really... even 3200 is overkill since the axles are the weak link at 5200..

Like I said... a CLUSTER
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Old 08-10-2018, 03:33 AM   #10
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So, technically I could use these for tires.. Defender LTX M/S - Size: LT245/75R16 120/116 3042 lbs. They are roughly (30.4") the same diameter and width as the OEM

Still 884 lbs. more than the axle limit 3042 x 2 = 6084
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Old 08-10-2018, 10:44 AM   #11
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So, technically I could use these for tires.. Defender LTX M/S - Size: LT245/75R16 120/116 3042 lbs. They are roughly (30.4") the same diameter and width as the OEM

Still 884 lbs. more than the axle limit 3042 x 2 = 6084
"Like said above... don't need 3420 tires... since the wheels are only 3200... and really... even 3200 is overkill since the axles are the weak link at 5200.."

The problem is twofold. Minimum safety is the trailer manufacturer's decision and to top it off they must certify their decision.

The LT tire you suggest could have also been the trailer manufacturer's decision. We can only second guess why in wasn't used. Surely it wasn't because of availability, it's a widely used size and design and very capable of supporting 5200# axles.

Here in this statement from the tire manufacturer is another problem. It's not just Michelin, it's an industry wide standard that supports all vehicle manufacture Original Equipment selections displayed on federal certification labels.

"Michelin: Never choose a tire that is smaller in size or has less load-carrying capacity than the tire that came with the vehicle."
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Old 08-10-2018, 11:44 AM   #12
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In another recent thread, I think the "real reason" was revealed as to why Keystone and other manufacturers make many of the decisions they make. It's about the cost of the component as much as it is about the suitability of the component. There is a discussion of why Dexter retained the 4400 lb axle after buying ALKO. The statement that was related to the poster by Dexter is because it was a "profitable axle system" and that "replacement parts are more than double the price of the 5200 pound axle parts".... He went on to say that since the axle fails often, it's a "cash cow" for the company, so they keep producing it.

Whether any of that is true is something I can't substantiate, but if the axle "works with the GVW/tires/wheels and meets mandatory minimums, if there are two choices, one costing $100 and the other costing $125. I think we all know which axles would be installed. Same for springs, tires, wheels, stoves, refrigerators, mattresses, TV's, stereo, door systems, windows (and the list goes on and on until the trailer is delivered to the dealer for sale)....

It's about money while meeting minimum requirements, not about what makes the most sense to a buyer or to his satisfaction. After all, it seems the attitude in Elkhart/Goshen is, if you don't buy it, someone else is waiting with cash in hand to put down a deposit.....
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Old 08-10-2018, 01:11 PM   #13
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Yeah... I deal with the cost thingy daily when designing.. But I do try to make some sense in what I choose...

But this is why we're thinking of selling this trailer and moving up to one with 7K axles and a 12" drop frame.. Just need to make up our minds before spending the money for wet bolts and new tires... Tires are just two years old, but we had one get a fencing staple in it last year and I had to buy a Goodyear Endurance at the moment...

So before we begin our camping season in a month or two I need to decide on buying one Carlisle to match the three I have now and move the Endurance to the spare or buy four new Endurance and move the used one to the spare...

OR..... SELL THE 333MKS & Buy a NEW TRAILER..

ANYBODY INTERESTED.....
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Old 09-11-2018, 06:49 AM   #14
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Quote:
Originally Posted by Javi View Post
So, technically I could use these for tires.. Defender LTX M/S - Size: LT245/75R16 120/116 3042 lbs. They are roughly (30.4") the same diameter and width as the OEM

Still 884 lbs. more than the axle limit 3042 x 2 = 6084
I've thought it prudent to come back and address your hypothetical replacement tire size above.

Although it does have an identical maximum load capacity as any LT235/85R16 LRE tire, the minimum rim width may be a problem. All LT245/75R16 LRE tires have a minimum rim width requirement of 6.5".
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