Revised GVWR after axle upgrade??

[TundraTower]

We have a 2014 TT that came with two 3,500 lb axles/springs and very little payload capacity. By the scales the axle/springs run at 96% of capacity at trip weight and within the GVWR. The springs were always flat, it had developed a lean on the kitchen side, and we bent one axle on a long trip out west last summer.

This winter I had the 3,500 lb axles replaced with 5,200 lb axles and springs. This is much better suited for even the original GVWR and I can tow with more confidence.

I know several folks here have done this modification. I'm just wondering if anyone has found a way to rationalize a higher GVWR for the upgraded trailer system? Not from the OEM of course, but a new higher guideline for your own situation.

The new axles, springs, tires, and wheels weigh 200 lbs more than the stock components. I think I can increase the GVWR number by that 200 lbs because that is all below the frame and limited only by trailer brake capacity which now far exceeds what I need.

The next limiting factor on GVWR seems to be the frame/tongue assembly, and that is very difficult if not impossible to evaluate. I tried to decipher how far up the model line the OEM used that frame versus those respective GVWR's, but that is far from exact and only adds a couple of hundred pounds at most.

For those of you that have done this modification, are you just staying around the original GVWR and towing with more confidence and better handling, or have any of you increased the payload limit with the new suspension by some calculation or rationalization?

I would like to have more payload but I know that frame was built to a price point just like the axle sizing. I've tried to explain to DW that the cast iron stove and hot tub are probably not going to make it on the load manifest either way.

Thanks

[boosTT]

I reach out to the frame manufacturer (BAL?). Its a standard frame. It will have a rating.

[harley4275]

I have a 2013 that had 3500# axles and springs and like you ,I did the scales loaded and was under the weight by 600 lbs ...but springs were flat and tires were bottoming out on bottom of trailer wheel well. One axle straightened so had 4400# axles and matching springs installed. (4400s are 5200s with original 10"brakes instead of 12" brakes.)Kept original rims and they supplied same size tires ,so my GVWR stayed the same as tires are now the weak point. I guess you could say the frame also.
I added wet bolts too and a much quieter ride.

[dodge_guy]

I looked up that model and it looks as though it is a stacked frame (I don't know what the industry calls it) where the Aframe is under the trailer frame. If that is the case that is a very stout frame. there are different height frames 6" 8" and I think 10". I believe yours is an I beam style and 8 or 10" tall. My 07 Cherokee has that same setup (not sure on height but it is an Ibeam frame) and has an 11,200lb GVWR and a 7100lb dry weight. my axles are also 5200lbs ea. You could call around and find a place that knows about recertifying for increased GVWR. I know Limo manuf. do it to there cars and they only add HD springs.

I wouldn't think twice about it, you made it safer than the factory did!

[Ivylog]

If you could put all of the increase capacity over the axles you could use all of it but the further from the axles the weight is put the less the increase can be used without knowing the strength of the frame.

If they went cheap on something as important as axles and tires what else did they skimp on.

[donn0128]

Now, frame has become your weak link. The frame,springs,axles,tires, and wheels were all matched to a specific weight limit. All you have done is band aided the situation. Not saying the frame will instantally fail the minute you go 10 pounds over its rating, but fail it can sooner or later