Hybrid Tow Capacity Underrated?

I'm starting to suspect Toyota didn't bother to calculate a tow rating for the hybrid specifically.

Comparative Specs:

.................................Curb Weight........Wheelbase..........HP/Torque........OEM Tow Rating

Colorado ZR2 4WD...........4,800...............131.4"...............310/430.................7,700
Tacoma TRD Pro (hyb)......5,100...............131.9"...............326/465.................6,000
Tacoma OR nonhybrid.......4,630...............131.9"...............278/317.................6,300

I towed my ~6,000 lb boat this weekend with my Hybrid OR, no issues. Didn't feel like I was even close to the limits.

Are there other factors aside from the above specs that determine tow rating? Is Chevy overselling the Colorado, or maybe using a different calculation method?

 

maybe..... thats why theyre frames are bending... https://www.tacomaworld.com/threads/chevy-colorado-destroys-frame-while-towing.615725/

 

Tow rating includes being able to stop the total weight of truck, passengers, cargo, and trailer.

HV taco is heavier than non-HV, so tow rating would be reduced.

My guess is the larger/regenerative brakes on the HV are why tow rating is reduced 300# while vehicle weight is 470# more.

 

Good callout on braking.

 

how do regenerative brakes work?

 

tl;dr version is the electric motor becomes a generator - slowing the axles/driveshaft as it converts the energy into battery charge instead of friction/heat of conventional brakes.

Hybrids still have conventional brakes of course. My understanding is they're larger rotors though that may also apply to some non-hybrid trims. I've not researched that aspect.

 

so the brakes are just regular brakes but bigger.... and the electric motor does the "braking". none of which applies to reduced towing other than the weight of the truck being heavier.
some people may get confused and think regenerative brakes are some magic thing.

 

I don’t know how effective regen is in a Tacoma that’s such a mild hybrid and small battery, but in a full EV towing it’s about 85% as effective as a diesel exhaust brake. I towed down a lot of steep Colorado mountains without needing to touch my brakes, similar to with a diesel exhaust brake.

 

You towed with the Tacoma hybrid or another full/EV?

 

Another full EV truck.

 

Having looked a bit further, it seem the Off-Road has the larger 340mm front brake rotors as well.

Gross Combined Weight Rating (GCWR) is GVWR plus towing capacity. GVWR of the TRD Pro hybrid is 6780lb and 6240lb for the TRD Off-Road DCSB. (link) So that puts the Pro hybrid at GCWR of 12,780lb and the OR at 12,540lb. (240lb less)

Something is allowing Toyota to rate the hybrid at a 240lb higher GCWR - any ideas other than the hybrid motor? It's not magic, but it can add deceleration force - though how much so would depend on tires, traction, braking force from the conventional brakes, etc.

 

Horsepower/torque is probably the smallest factor for small trucks. Wheelbase, suspension, and brakes (and the associated payload) are much more critical.

Pulling is the easy part, and a weaker could pull the same weight, just accelerating slower. Try an emergency stop at highway speeds and see if the truck still feels underrated. (Not saying it has a problem now, but that's a more critical test).

 

[QUOTE="Something is allowing Toyota to rate the hybrid at a 240lb higher GCWR - any ideas other than the hybrid motor? It's not magic, but it can add deceleration force - though how much so would depend on tires, traction, braking force from the conventional brakes, etc.[/QUOTE]

Maybe the Pro's skid plates, sliders, ARB bumper (?) and seats add up to 240lb?

 

That's fair. These are the numbers for my '24 OR hybrid vs the '23 SR5 Tundra I traded in:

.................Curb Weight.........HP/Torque........OEM Tow Rating.....Wheelbase

Tundra............5,390...............348/405.................8,300...............145.7"
Tacoma...........5,100...............326/465.................6,300...............131.9"

The brakes and suspension may also be rated different, but there's a big difference in wheelbase. Not so much compared to the Colorado.

 

I think you need to be looking at GVWR, not curb weight. Tow rating will be considering the vehicle's abilities when fully loaded with passengers and cargo, not sitting empty at the curb.

Those are already factored into the GCWR and GVWR. Also, curb weight difference between Pro and OR hybrid is 70lb.

 

Good points. Makes sense to me.

 

Y'all haven't mentioned bearings.
The bearings in the axles and hubs also have a load rating.

 

I'd expect those to be among the many things the manufacturer considers when specifying the GVWR & tow rating.