Nise high towing How much additional wieght on rear tires

[aruba5er]

They keep raising the trucks and I am running about 2 inches nose high. I blew 3 tires in March and still trying to figure out why. How much more weight is on the rear tires because of "nose high" I had to adjust the hitch 3" up when I went from 2007 2500 HD to 2011 Hd and the new 2017is almost 3" higher again. Because of that I have decided I don"t need a new truck. I thought that the equalizers would change the weight to "equal" but does it? Any thoughts?
For what it's worth, they could drop the truck 11" and still have room for tires. And it would be a whole lot easier for us old farts to get into.

[Dayle1]

mapguy wrote:




Engineering wise -the equalizer in a leaf spring trailer suspension only function is to allow independent axle articulation as the axles move through suspension travel range.

Remember, that a typical leaf spring trailer suspension only has 2-3" travel from the neutral position(frame level)-compression or rebound wise.

Being nose high takes the trailer suspension out of the neutral position and compromises the suspensions ability to absorb roadway irregularities.

Being nose high is not really about the weight distribution, but about the compromise it imparts on the suspension system working properly.

Agree with everything but your opening statement. If the only goal was to allow independent axle movement, there would be no connection between the leaf springs, each axle would have a setup like typical single axle leaf springs. The equalizer does allow static and dynamic forces acting on one axle to alter the eye to eye spacing of the other spring and therefore attempts to balance the forces between the two axles.

[Wadcutter]

I helped a buddy set up his 5er as I had access to a certified scale. The difference between him running level and 2" high in the front was 250 lbs on the rear axle. 250 is within the +/- on a certified scale.
4" high was a few over 300 lbs more on the rear, still within the +/- tolerance on a certified scale.

[mapguy]

Ductape wrote:

Dayle1 wrote:
Just my opinion, but the equalizer should balance the weight between axles. But, with the trailer nose high, the rear axle has limited remaining suspension travel and so the rear tires experience more abuse. That is the downside.

Not just your opinion, but a fact. 😉

Posts to the contrary are incorrect.

Engineering wise -the equalizer in a leaf spring trailer suspension only function is to allow independent axle articulation as the axles move through suspension travel range.

Remember, that a typical leaf spring trailer suspension only has 2-3" travel from the neutral position(frame level)-compression or rebound wise.

Being nose high takes the trailer suspension out of the neutral position and compromises the suspensions ability to absorb roadway irregularities.

Being nose high is not really about the weight distribution, but about the compromise it imparts on the suspension system working properly.

[Cummins12V98]

rhagfo wrote:

Cummins12V98 wrote:
"Yet together both axles on the fiver came in at... 8000# so not sure how that happens"

I have this happen all the time, it's from weighing one axle with it near the scale pads edge.

True weight is the combined with both axles on center of scale.

These are likely a bad set of scales or very old, modern use load cells and should weigh accurate even at the edge.

I weighed at scales built in the last 5 years in WA on I-5 recently. Weighed front RV axle 8,720#, rear axle 8,820# that combines to 17,540#. Both axles on center came in at 17,760# that is a 220# difference.

Maybe the CAT scales would be closer???

[rhagfo]

Cummins12V98 wrote:
"Yet together both axles on the fiver came in at... 8000# so not sure how that happens"

I have this happen all the time, it's from weighing one axle with it near the scale pads edge.

True weight is the combined with both axles on center of scale.

These are likely a bad set of scales or very old, modern use load cells and should weigh accurate even at the edge.

[Cummins12V98]

"Yet together both axles on the fiver came in at... 8000# so not sure how that happens"

I have this happen all the time, it's from weighing one axle with it near the scale pads edge.

True weight is the combined with both axles on center of scale.

[laknox]

aruba5er wrote:
They keep raising the trucks and I am running about 2 inches nose high. I blew 3 tires in March and still trying to figure out why. How much more weight is on the rear tires because of "nose high" I had to adjust the hitch 3" up when I went from 2007 2500 HD to 2011 Hd and the new 2017is almost 3" higher again. Because of that I have decided I don"t need a new truck. I thought that the equalizers would change the weight to "equal" but does it? Any thoughts?
For what it's worth, they could drop the truck 11" and still have room for tires. And it would be a whole lot easier for us old farts to get into.

Personally, I'm 3-4" nose high and I've not noticed any temp differential between front and rear tire when towing, either empty or loaded. I =do= notice sunny/shade differences of 10-20 degrees, though. This being said, I simply don't think there's enough weight transfer between front and back axles to worry about, especially since I'm upgraded from D to E-range tires. This is =my= experience, with =my= rig; YMMV... I do know that some trucks have spacer blocks in their suspension that can be removed to lower the truck some.

FWIW, I do agree that today's trucks are just too d@mn high, and it's done for marketing and nothing else.

Lyle

[Fisher_Bill]

I thought my nose was a little high and I weighed in at the public scales on the highway and was surprised at how the weight was distributed;

Front axle.... 4700#

Front and dual rear together... 10,500#

Rear duals alone... 5750#

5er axle #1... 3750#

5er axle #2... 3750#

Yet together both axles on the fiver came in at... 8000# so not sure how that happens but those are my weights per axle so both 5er axles weighed the same, YRMV.

Bill

dapperdan wrote:
The further off level you are the more weight will be transferred to the low-side axel. In your case that would be your rear axel.

The easiest and smartest way to figure out YOUR weight situation would be to go to a scale and weigh the front axel SEPARATELY from the rear axel of your trailer, you'll be surprised at the difference.

Dan

[Cummins12V98]

With my 23K RV before adding 3" risers my rear axle weighed 1.200# more than the front!

[Bipeflier]

I exchanged the stock rear spring hangers for ones to drop the rear end 2 inches on my Silverado. Drop Shackles

Truck sits just slightly tail high empty and nearly level hitched up.

2 inches makes a big difference on the truck to trailer clearance issue.

[time2roll]

Probably need better tires.

[jmtandem]

Having towed multiaxle trailers for a living and having had many a trailer weighed in a loading yard and by DOT I found out the hard way the suspensions equalizer bars do not equalize the weight

Absolutely correct! The axle equalizers do not equalize the weight between the axles. One trip across the scales weighing both axles will give you the information you are looking for. Also, the axle's weights are not equal side to side either. Typically the side with the refrigerator or the slide out is heavier. Weigh each wheel and you, too, will find this out.

[ScottG]

dapperdan wrote:
The further off level you are the more weight will be transferred to the low-side axel. In your case that would be your rear axel.

The easiest and smartest way to figure out YOUR weight situation would be to go to a scale and weigh the front axel SEPARATELY from the rear axel of your trailer, you'll be surprised at the difference.

Dan

X2. You can verify this by looking at the spring and seeing it unload on the front as well as seeing the rear tires bulging more with the added load.
An equalizer only serves to try and keep the tires on the road.

[JIMNLIN]

Having towed multiaxle trailers for a living and having had many a trailer weighed in a loading yard and by DOT I found out the hard way the suspensions equalizer bars do not equalize the weight 100 percent. Its possible to over load the rear axle with a nose high trailer BTDT and a costly mistake by a rookie owner/operator.

Now....one size don't fit all as some folks use tires on their trailers with enough reserve capacity that eliminates overloading in this case vs another trailer with tires that have little to no reserve capacity.
Now add the fact some folks for unknown reasons don't use max sidewall pressures in their tires on a trailer. This causes the rear tires to operate in a run hot condition.
And of course tire quality. A poor quality tire won't last long if its ran hot continously in this situation.

As others say get some scaled axle weights for a base to start with.