CAT Scale numbers (still a newbie to towing)

saseals wrote:
Can I ask where you did your weighing? I weighed my TV at a Pilot but was worried the whole time that I was in the way. What do they charge for multiple weights? I think I paid $11 for the TV weight. Now that I have a different trailer, I need to do some more weighing.

CAT scales at two different truck stops. When I went they weren't busy plus getting the weight only takes a second so you really aren't in the way, especially since I had to move off the scales after each re-weigh to adjust my hitch/drop the trailer. I paid $11 for the first weigh and $2 for each additional re-weigh as long as its within 24 hours.

My wife's uncle has used the scales at the weigh stations that are off the highway that you see the truckers all pulling into. I'm not sure if he paid for those but I assume those would be busier than CAT scales at a truck stop and probably more difficult to do your adjustments and re-weighs.

The CAT scales has a website that you can use to locate the closest one to you.

Can I ask where you did your weighing? I weighed my TV at a Pilot but was worried the whole time that I was in the way. What do they charge for multiple weights? I think I paid $11 for the TV weight. Now that I have a different trailer, I need to do some more weighing.

atwowheelguy wrote:


It looks like you have done a good job of adjusting the WDH. The rear axle is 10 lbs. under the weight limit. The vehicle weighs 7580 lbs. attached to the trailer. That also may be close to the GVWR. Was the family in it when it was weighed?

Yes, the whole family was in the vehicle including the 2 dogs. There was a few things that were packed in the back of the Expedition that can be moved to the trailer but I wanted to weigh things up identical to how I had it setup when I weighed it the first time 2 weeks prior.

MikeJulieGDImagine wrote:
Hit the scales again on the way to our site yesterday to re-weight with adjustments and here's where I'm at:

Expedition By Itself
Steering Axle - 3380 lb
Drive Axle - 3600 lb
GVW - 6980 lb.

Expedition and Trailer (No WDH)
Steering Axle - 3020lb
Drive Axle - 4700 lb
GVW - 7720 lb.
Trailer Axle - 5960 lb
GCW - 13680 lb.

Tongue wt. 7720 - 6980 = 740 lb.
Trailer wt. 13680 - 6980 = 6700 lb.
% tongue wt. 740/6700 = 11.0%

Expedition w/WDH (8 Chian Links from the bar)
Steering Axle - 3280 lb
Drive Axle - 4320 lb
GVW - 7600 lb.
Trailer Axle - 6080 lb
GCW - 13680 lb.

I decided since I was there I would give it one more go at 7 links
Expedition w/WDH (7 Chain Links from the bar)
Steering Axle - 3340 lb
GAWR 3700 lb.
Drive Axle - 4240 lb
GAWR 4250 lb. !
GVW - 7580 lb.
Trailer Axle - 6100 lb
GCW - 13680 lb.

So at 7 links from the bar the steering axle is only 40 lbs different than the Expedition with no trailer hooked to it. Drove to our site 110 miles from the scales and I couldn't believe what a huge difference it was from last weekend. Much more comfortable drive to the point my wife as a passenger could tell it was better. It was more solid, didn't feel as bumpy when we hit any uneven spots in the road and when we got hit by wind instead of feeling squirmy and getting pushed I could feel the Expedition hold steady and the trailer almost 'snap back' in line. Thanks the info on needing to go back and get re-weighed with the different setups.

It looks like you have done a good job of adjusting the WDH. The rear axle is 10 lbs. under the weight limit. The vehicle weighs 7580 lbs. attached to the trailer. That also may be close to the GVWR. Was the family in it when it was weighed?

I am approaching 30,000 tow miles on my F-150 in three years and an additional 46,000 miles of day to day driving miles. I replaced the original P tires with the exact same set of P rated Wranglers. I also replaced the rear shocks at 50,000 miles with Bilsteins. My TT crosses the scale at a weigh of 6200 to 6400 lbs with about 750 lbs on the tongue.

When we travel we set the Blue Ox to 8 or 9 links depending on how it is loaded. I always set the TT level or slightly nose down. It has 750 lbs. bars.

When towing I run 40 psi in the tire rather than the 32 lbs on the door jamb.
According to the CAT scales I am near my max cargo but the E-boost engine and towing package works fine.

Keep in mind that running a vehicle at or near its ratings is going to increase the wear and tear. There is not much you can do about that, except buy a bigger vehicle.

Well I looked up some info for giggles..

(c) Its load rating shall be that specified in a submission made by an individual manufacturer, pursuant to S4.4.1(a), or in one of the publications described in S4.4.1(b) for its size designation, type and each appropriate inflation pressure. If the maximum load rating for a particular tire size is shown in more than one of the publications described in S4.4.1(b), each tire of that size designation shall have a maximum load rating that is not less than the published maximum load rating, or if there are differing maximum load ratings for the same tire size designation, not less than the lowest published maximum load rating.

https://www.gpo.gov/fdsys/pkg/CFR-2011-title49-vol6/xml/CFR-2011-title49-vol6-sec571-109.xml

It would have to be already derated.

You know the lawsuits that would be involved it you relied on someone doing math to figure the load capacity of a tire.

Example: My tires says 44 psi @ 2535 lbs. I load my truck to 10100 lbs. I get blow out and cause accident and kill someone.

Whos going to tell me Im at fault and I should have known to do the math to derate my tire and I maliciously over loaded my truck.

If it was a dual use tire, such as passenger or truck then im sure they would have both ratings on the side wall.

Just like tires for a dually set up. There are two weight ratings on the side wall.. Single and duelly..

Public misinformation?

Id like to see an example of a passenger car tire that can be used on a truck.

Just trying to get educated here and have a friendly discussion regarding this. Maybe a new thread should be started as posting on top of someones post and going off topic normally is frowned upon..

lawrosa wrote:

Guess I missed your tires load rating in my reply above but divide the 2601 lb number by 1.1 = 2365 lb capacity for your P tires.

OEM already derates the tires AFAIK.. His tire rating is what it says on the side wall.. 2601 @ 44 psi.

Ill find documents supporting this if needed.. After all your not going to fit a 265 70 r 17 on a car are you.

A OEM tire or a replacement tire have the same load rating stamped on the sidewall.
You won't find a credible document stating that the P tires sidewall load capacity is a reduced number.

RMA
Chapter 3 - Tire Replacement Guidelines
Tire Size, Inflation & Load..........Chapter 3, page 37
Passenger tire load carrying
capacity must be reduced by dividing by
1.10 for light truck applications. For example:
P235/75R15 which has a maximum load capacity for
passenger vehicle application = 2028 lbs. For a light
truck application, using the formula, the maximum
load capacity would be 2028 / 1.10 = 1844 lbs.

**************************************

per 49 CFR FMVSS safety regs 571.110

S4.2.2.2 When passenger car tires are installed on an MPV, truck, bus, or trailer, each tire's load rating is reduced by dividing it by 1.10 before determining, under S4.2.2.1, the sum of the maximum load ratings of the tires fitted to an axle.

Since this is my first experience with towing I don't have anything to compare it with to know whether or not having 'P' tires is creating a problem. Since I've read so much about the positives of having 'D' or 'E' tires when towing I figure I will put a set on in the near future.

Yes you should upgrade the tires to an LT with that much weigh on them.

But watch out if you go to a higher load range as your rims most likely cant handle the higher psi. These tires are usually 80psi max or so.

Do your homework...

Guess I missed your tires load rating in my reply above but divide the 2601 lb number by 1.1 = 2365 lb capacity for your P tires.

OEM already derates the tires AFAIK.. His tire rating is what it says on the side wall.. 2601 @ 44 psi.

Ill find documents supporting this if needed.. After all your not going to fit a 265 70 r 17 on a car are you.

JIMNLIN wrote:

op wrote:
Max tire pressure is 44PSI which I already air up to when I'm hitched up and the lb rating is 2601. 'E' rated tires are coming in the near future.

Guess I missed your tires load rating in my reply above but divide the 2601 lb number by 1.1 = 2365 lb capacity for your P tires. A load D or E will stiffen the tire and eliminate that problem...if it was one.

Since this is my first experience with towing I don't have anything to compare it with to know whether or not having 'P' tires is creating a problem. Since I've read so much about the positives of having 'D' or 'E' tires when towing I figure I will put a set on in the near future.