TT Weight limits: theory and reality
There are a ton of threads here regarding the proper matching of TV and TT. Based on what I learned here, I made a very expensive decision to upgrade my brand new 1/2 ton to a 1 ton TV so that I would...
Forum Discussion
The truck makers design and test the brakes for the GAWR its on.
The F150HD with a 4800 RAWR and a 4050 FAWR = 8850 lbs of braking performance. Now if the F150 is pulling a trailer with two 3500 lb axles the GCW has a total of 15850 lbs of braking performance.
This is one reason a same F150 HD truck that is operating commercially may do so legally with a GVW at the sum of the GAWRs.
And of course thats why many RV folks use the trucks RAWR to figure how much weight the truck axles/tires can safely carry.
The chassis will easily handle the sum of the GAWR. Remember rating are determined by a components lowest working rating.
The truck will easily pass the minimum tests per the FMVSS's.
NHTSA says this about components of the GAWR:
"Gross Axle Weight Rating is the rated load-carrying capacity of an individual axle and wheel assembly. (It represents the load that may be steadily sustained by the components in the system; i.e., tires, rims, hubs, bearing, axles, brakes, suspension, sub frame, etc. with the GAWR limited by the components with the lowest working rating".
RMA
• GAWR: Gross Axle Weight Rating (for each axle) -
The maximum weight rating that the components
(tires, rims/wheels, brakes, springs, and axle) of
each axle are designed to support. This is
determined by the lowest design capacity of any
component. In other words, if the wheels have the
lowest design capacity of any component on that
axle, installing tires with a higher load capacity
does not increase the GAWR. By regulation, the
tire load rating times the number of tires on that
axle must equal or exceed the GAWR for that axle.
The F150HD with a 4800 RAWR and a 4050 FAWR = 8850 lbs of braking performance. Now if the F150 is pulling a trailer with two 3500 lb axles the GCW has a total of 15850 lbs of braking performance.
This is one reason a same F150 HD truck that is operating commercially may do so legally with a GVW at the sum of the GAWRs.
And of course thats why many RV folks use the trucks RAWR to figure how much weight the truck axles/tires can safely carry.
The chassis will easily handle the sum of the GAWR. Remember rating are determined by a components lowest working rating.
The truck will easily pass the minimum tests per the FMVSS's.
NHTSA says this about components of the GAWR:
"Gross Axle Weight Rating is the rated load-carrying capacity of an individual axle and wheel assembly. (It represents the load that may be steadily sustained by the components in the system; i.e., tires, rims, hubs, bearing, axles, brakes, suspension, sub frame, etc. with the GAWR limited by the components with the lowest working rating".
RMA
• GAWR: Gross Axle Weight Rating (for each axle) -
The maximum weight rating that the components
(tires, rims/wheels, brakes, springs, and axle) of
each axle are designed to support. This is
determined by the lowest design capacity of any
component. In other words, if the wheels have the
lowest design capacity of any component on that
axle, installing tires with a higher load capacity
does not increase the GAWR. By regulation, the
tire load rating times the number of tires on that
axle must equal or exceed the GAWR for that axle.
