Axle upgrade questions

JIMNLIN wrote:

Adding more info from sticker on side..

GVWR 10500 Lb
GAWR 5080lb each
Tires ST225/75R15 D Planning to upgrade to goodyear E range
Axles Dexter 184357 5200lb

Sound like the mfg used 5200 lb axle and then derated them with 5080 lb springs.
Any wayz....the trailer may weigh 10000 lbs fully loaded. Now subtract hitch weight = around 1400 lbs leaves 8600 lbs on the axles or 2150 lbs per tire.
Several reasons a trailer can have too much axle/tire capacity.
You really need to weigh the combo on a set of CAT scales for your trailers axle weights or just use a certified single platform scales with just the trailer axle on the platform. That way you will know what you have and what you need....and don't need.

My 1997 5th wheel rv trailer has 5200 lb axles and around 2500 lbs per tire capacity requirements.
This trailer has lots of miles on it with 51k and 55k miles the first two sets and at 48k I'm looking to replace them now with the same LT215/85-16 E at 2680 lb capacity per tire. Ran the first set for 7 years and 55k miles with no issues other than keeping them pumped to full 80 psi sidewall pressures 352 days a year.
I use Firestone LT Transforce HT or Cooper LT Discoverer HT-3 and BFG LT Commercial TA 2 .
Edit; add tire brands /sizes.........jim

Great info. Thanks for the post and education! So my 5200lb axles may not be undersized since I did not calculate the tongue weight. Great point. I still have the issue of excessive inside tire wear. I need to replace these tires ASAP and am in the process of doing so since we have multiple trips planned over the coming weeks, but I am concerned that over another 10k miles this new set will be destroyed just like the factory tires. I checked with 2 trailer shops in my area (shops that sell heavy duty and standard commercial grade trailers) and neither do axle / trailer alignment as a service. Not sure where to go from here.