Tow ratings

Hello folks. New to the site. Im on my 5th Tundra since the yr 2000. Just purchased a used 2019 SR5 Crewcab with the 38gal fuel tank, which i sorely needed to pull my 30ft travel trailer on long haul trips, and i notice in the owner's manual that the tow rating takes a 1000lb hit for the 38gal fuel tank! Go's from 9800 lb down to 8800 lbs! What gives? This makes no sense, as the larger tank and extra gas cant weigh much more than an additional 100 lbs. Does anyone know what Toyota is thinking on this?

 

It's not just the tank size. The crew max cab is heavier than the others, so that also plays a part. If you have a sunroof, that's more weight, too.

 

^ beat me to it!

9800lb max is usually for a truck without options (as opposed to limited, plantinum, 1794); usually the larger gas tank requires additional options of packages, which make up the bulk of the weight. It's really quite simple, though: the truck is rated for 16,000 lbs gross combined - your truck plus the trailer. So the gas tank, extra fuel, extra options, etc, can add to the curb weight of the truck, subtracting from the tow vehicle weight rating. It's not that your truck is rated to pull less - just that it will reach max gross combined (16k) faster than another truck with fewer options.

Easiest thing is to weigh the truck and trailer on a scale, then you know where you sit. My travel trailer was within 100 lbs of the yellow tag unloaded weight with full propane tanks, batteries, and some junk under the front bed.

 

Thank you for your responses. I can see that additional weight on the truck gets it closer to its MAGW, and the MACGW, but still dont see how it reduces its tow rating. Throwing 1000 lbs of cargo in the truck doesnt change the tow rating, it just gets you closer to it. But i agree that the best thing to do is put it all on the scales and make sure its all under the 16000 lb limit. Thanks again.

 

I know how it looks like you have a smaller tow rating on paper, but you really don’t. Pull stuff out of the truck and now you have a higher tow rating - on paper. The truck platform is rated for 16k gross combined; subtract curb weight of your particular model (with a driver and furl) from that 16k, and THAT is your tow rating. It’s that simple.

Many other manufacturers sprinkle pixie dust on their trucks to increase the tow rating in up-optioned trucks but it all just boils down to gross combined. That’s it. There’s nothing different mechanically between your up-optioned limited crewmax and a base double cab; axles, brakes, motor, transmission, driveshaft, u joints, springs, etc - all the same as long as you at comparing same motor and drive (2wd, 4wd). I did mention springs as there are a few different options, and most manufactures have a “special” spring package for their max tow vehicles, but pretty much all 5.7 tow package vehicles have the same spring, or close enough to it.

So, again, your tow rating is only lower in comparison because of the vehicle curb weight that increased with your options. That beast can still move the same amount of weight as any other 5.7 tow package tundra.

 

I don’t even see 8800 lbs in the owners manual. How did you come up with that number? What is your model code?

 

My SR5 crewmax is rated for 9400 lb. That would max out my payload without my family in the truck, too.

So, for me, as long as neither axle is overloaded, I’m ok being a bit over payload.

But even using my truck this way, I’m getting to the point where I need to jump to an HD truck.

 

Start here. https://www.tundras.com/threads/tow-ratings-guide-how-to-be-safe.39211/

 

It's not the larger tank but the extra fuel in that tank. Curb weight includes full fuel. The tow rating is dependent upon the payload of the truck and the models with larger fuel tanks have less payload. Remember the GVWR is the same but the curb weight is different. Toyota uses a formula which includes a weight for the driver and possibly the passenger to determine available payload left for tongue weight. The manual states tongue weight should be between 9 & 10% of the trailer weight. I don't know which number they use but lets assume 9%.
Tossing out some hypothetical number just for the sake of explanation. Truck has a payload of 1,300#. Driver and pax combined weight is 300#. This leaves only 1,000# for weight distribution hitch and tongue weight. Estimated WDH weight to be 100# and you have 900# left for tongue weight. There's your 10,000 max towing.
Don't forget anything else you take with you reduces your available payload and therefore your towing capacity.
Since many trailer manufacturers build erring on nose heavy, you really must be careful when picking out a travel trailer.

 

2019 Toyota Tundra owner's manual, Ch4, pages 177‐181, weight charts...there is an asterisk#4 with revised GCWR and TWR....the weights with the #4asterisk are for models with the larger fuel tank and towing package. For certain crewmax models, there is a 1000lb hit for the 38gal tank. Seems excessive.

 

Is this a matter of buyers remorse or are you simply sharing an observation of the weight ratings?

Trying to figure out how we can help you other than saying the vins are likely representing differently optioned vehicles driving the difference in ratings and that they are likely using the standard referenced on those pages to determine the TWR.

Scales will be your friend and help you figure out the truth for your specific setup.

 

Because the 38 gallon tank is only included with certain packages. Those packages include other features.

You're so focused on the tree you aren't seeing the forest.

 

No buyers remorse. Just was curious if there was a good answer to why the tow rating and the max combined gross weight rating took such a big penalty for the larger fuel tank. I dont think the difference of the weight of the larger tank and 12 extra gallons of gas, nor anything that comes included in that package could account for a 1000lb difference...that's a half-ton! So i posed the question just out of curiousity. Thanks for responses.

 

I'm trying to do that math as well.

Sunroof and a bigger tank and a slightly bigger cab, minus a smaller box does not work out to a 1000 lbs reduction.

Common core math?

 

Too many variables for anyone not Toyota to know, but I have faith in the auto manufacturer and the safety regulators to ensure every vehicle on the road meets some basic standard for safety.

While we view it as some metal and a few gallons of liquid, it could have to do with results from the towing standards used for their ratings, an engineering decision, or some other topic ($$$$) we're just not aware of. Regardless, I'm still at peace with what the truck is rated for and can actually do, as proven for 15 years of production for this one platform.

 

Maybe it's because 100lb more weight in the truck from larger gas tank filled up reduces the weight capacity of the truck left for tongue weight by the same amount. So... since tongue weight should be at least 10% of trailer weight taking 100lbs off the trucks surplus load capacity takes 1000lbs off the trucks towing capacity?

 

Bingo.

 

As others have recommended, a trip to the scale will make things easier to figure out. I have a 2023 4WD Limited Dbl cab 6.5 bed, pretty basic and have been travel trailer shopping the last few months. Getting close to purchase and started making myself insane looking at everything on the interweb, while everyone has an opinion, numbers are truth at the scale.

My door jamb sticker says I have payload 1490 lbs for occupants and cargo, after digging around Toyota website my model lists 1800 lbs payload
I just had some service done and a recall item came up that I need to downgrade my payload by 47.7 lbs for a spray on bedliner.

Door jamb says I have 1442.3 lbs of available payload for occupants and cargo.

Today's payload at the scale:

• 170# driver, 16 oz coffee
• eXtang rigid bed cover
• Westin Hdx stainless steel step rails
• Rear flip down bed step
• Bag full of tie downs

Curb weight per CAT Scales = 5940 Door jamb GVWR = 7310 Payload for more occupants, cargo, WDH, Hitch weight = 1370

I was surprised in a good way since the "occupants" has been debated in other threads if it includes driver. The difference from the door jamb to accessories was only 72 lbs. I did have a completely full tank. Good thing my main passenger and her dog add only 125#!