Endurance Tires

[TedS]

The GD load sticker on my trailer has the tire pressure at 80psi, which happens to be the Endurance max load rating at the pressure of 80psi. There is nothing wrong running tires at max load capacity. All the charts say is the pressure required for a particular load carrying capacity. The charts do not say to not air tires to higher load capacity. The charts show max load capacity rating and the air pressure to get that rated capacity. If I were to air the tires to 90psi, the load capacity rating would not change to a higher number.

[Cate&Rob]

If you upgrade your tires (such as from 80 psi E to 110 psi G) it makes sense to run the new tires at the original pressure spec. To go higher will definitely give the trailer a rougher ride. I have always run my E tires at 80 psi and with a 1000 lb side-to-side weight difference on my 303 there is no wear difference. No indication of one side being over inflated or under inflated.

Rob

[Madonnell]

If going by the Cat scale weight on a 303 and dividing by 4 this can make a bad situation. The 303 is known to have 1000# heavier side on the street/drivers side of the RV from the factory. This will of course change when loaded, increase for sure with the pantry.

Interesting. I had our fulltime 303 weighed by the RV Weigh folks at the 2021 Colorado rally, about 5 months after we hit the road. Surprisingly the 2 sides were within 75 lbs of each other. I even had 2 tires re-weighed with fairly consistent results. This was with a loaded fridge & pantry. I attributed this to the slide weight being inboard since the slides were in (therefore more evenly distributed between the left & right wheels), but never did the math to see if it made sense.

But thats a huge discrepancy witb your observation.

[Scott'n'Wendy]

Madonnell
Thanks for posting. Interesting numbers. I've never had my trailer weighed and just assumed the street side to be substantially heavier due to the kitchen slide and the bed room slide outweighing the dinette slide.
Wonder why the front axle is getting close to the 5200# rating while the rear axle is 500# less. Nose low by any chance?
What's also interesting is GD lists the 303 pin weight as around 1800# I believe.Yours is at 3K. You store gold bricks under the bed? LOL.

[TedS]

Scott'n'Wendy probably front axle weighs heavier because the trailer CG is forward of that axle and contributes to the hitch pin weight.

[Country Campers]

Madonnell

That is quite interesting to see those weights. GD does provide a sheet from the factory with total weight and side weights. Do you have this sheet? It would be in the package with all of the manuals.

Brian

[Cate&Rob]

Madonnell

I have seen "curious" data from the RV Weigh folks on other trailers.

I know that my 303RLS left the factory with the left side weighing 474 lbs more than the right . (4022 - 3548) and a pin weight of 1742 lbs. I confirmed pin weight with a Shurline scale (picture attached) This shows pin weight of about 2000 lbs with full propane and two lead/acid batteries added to the trailer as GD weighed it when it left the factory. Loaded for camping, this pin weight goes up to about 2200 lbs. I know from other measurements done while I was sorting out stronger springs for the left side to level the trailer (a much longer story) that once the fridge, pantry, cabinets and drawers on the left side were filled with "stuff", the side-to-side weight difference is greater than 800 lbs.

There are several numbers in your RV weigh info that don't make sense. I have never seen a 303 pin weight of 3000 lbs. There is just not that much storage space in the front end of the trailer. Are you confident that the data you received is for your trailer ?

Rob

[Scott'n'Wendy]

Scott'n'Wendy probably front axle weighs heavier because the trailer CG is forward of that axle and contributes to the hitch pin weight.

But I thought that would be affected by the nose high/low attitude and equal if level. Remember I'm an electrician.....lol

[TedS]

Scott'n'Wendy Nope. All about moment arms and reaction forces. The center of gravity is the location of the center of all distributed weights, nose to tail. I can place a jack about 12 to 18 inches forward of the front tire and lift the whole side balanced on the jack because it's located under the cg, putting equal weight fore and aft of the jack.

[TedS]

The suspension springs will add a complication to the nose attitude and weight distribution on the tires. The cg will always be forward of the front axle, otherwise the pin weight would be zero.

[Cate&Rob]

For normal trailer suspension with an equalizer between the forward and aft springs, there is an easy way to determine if your axles are carrying the load equally. If one axle is carrying more weight, the equalizer will be tipped in that direction. This is affected by how level the trailer is sitting (or being towed). Madonnell has mentioned that he has installed independent slipper spring suspension, so this would no longer apply. And . . . yet again . . . we have wandered way off the original topic of this discussion LOL!

Rob

[Scott'n'Wendy]

And . . . yet again . . . we have wandered way off the original topic of this discussion LOL!
Rob

Look!!! A SQUIRREL!!! lol

[Madonnell]

Madonnell
Wonder why the front axle is getting close to the 5200# rating while the rear axle is 500# less. Nose low by any chance?
What's also interesting is GD lists the 303 pin weight as around 1800# I believe.Yours is at 3K. You store gold bricks under the bed? LOL.

Well, maybe a generator & a bit of lead. After this weigh, I did move quite a bit of weight backwards, and the drive axle weight is much more reasonable at cat scales now.

But I'm not really sure how much I trust those RV Weigh weights, anyway. As others are pointing out, it don't make a lot of sense. I believe Cat scales more since those are stationary & have to be certified, but that only give you the steer/drive/trailer numbers without some extra work.

[TucsonJim]

But I'm not really sure how much I trust those RV Weigh weights, anyway. As others are pointing out, it don't make a lot of sense.

I had my rig weighed at the 2017 GDRV National Rally, which included the tire weights. The guy doing the weighing was in a bad mood because of the line, so he was literally throwing the scales around in a temper tantrum. The reading from one scale was astronomical compared to the others. I didn't trust the results at all. I prefer a CAT scale myself. And if I need an individual wheel position weight, I'll use the method Cate&Rob detailed in his post.

Jim

[Cate&Rob]

At a GD rally a few years back, another owner brought his RV Weigh numbers to me to see if I could make sense of them. His empty truck rear axle side-to-side was within 50 lbs. When hooked to his 5th wheel, one side (supposedly) went up several hundred lbs more than the other. This, from a point load on the centreline of the truck ?? I went to try and talk to the RV Weigh guys about how this could be. They refused to talk to me. I cancelled my weigh-in with them.

Rob