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I have a 2019 Limited Off-Road towing a 2019 27' Airstream. I love my Tundra, but I'm worried it's not enough truck for the trailer. Full weight on the trailer is 7600, but I'm not carrying full weight. When I'm towing downhill, I'm picking up significant speed (70) on steep grades. Please talk me through this. What should I be doing to prevent this from happening? I've tried shifting down, and it may work for a bit, but before I know it, I'm speeding back up. Sorry I can't be more truck talkie.
 

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I have a 2019 Limited Off-Road towing a 2019 27' Airstream. I love my Tundra, but I'm worried it's not enough truck for the trailer. Full weight on the trailer is 7600, but I'm not carrying full weight. When I'm towing downhill, I'm picking up significant speed (70) on steep grades. Please talk me through this. What should I be doing to prevent this from happening? I've tried shifting down, and it may work for a bit, but before I know it, I'm speeding back up. Sorry I can't be more truck talkie.
Are you using the gears? Tow haul mode? How steep of a grade are you going down? Between the trailer brakes and the truck brakes and the gears you should be fine if everything is set up right. Weight distribution hitch set properly? There's a lot of variables that go into it. How much load in the truck?

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Are you using the gears? Tow haul mode? How steep of a grade are you going down? Between the trailer brakes and the truck brakes and the gears you should be fine if everything is set up right. Weight distribution hitch set properly? There's a lot of variables that go into it. How much load in the truck?

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Using weight distribution. Tow/haul. Trying to use gears, but after a bit I'm as low as I can be but still fast. Not much load in the truck, but I don't have much payload. I thought my brake controller was set up correctly, but am wondering if that's my problem. Does adaptive cruise control play a role in this? Should I turn off?
 

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I am no expert on this subject, so I am pointing that out right up front.
You should NOT be using cruse control and expecting it to control your speed on down hills with a trailer. Use your gears in combination with your brakes. You do not want to over heat your breaks and lose them. I do not know what brake controller you have and some are not well thought of. I have a 26 ft Airstream. I drive almost solely on mountain roads. I did not have my brake controller turned up enough many times but unaware. Once on a very mountains road driving too fast I over heated the brakes on the truck and lost breaking power. My fault and very scary.

That event caused me to learn more about my brake controller. I talked to people that I trusted with more experience towing than I had. I was told you need to change your controller setting for the situation. I usually left it in one power setting for just about everything. I was running it on the highway at 7.8 (comparable to volts, 0 volts is no electric breaking power on the trailer and 12 volts would be a lot although some break controllers will go beyond 12 volts). For me 7.8 was too much breaking driving around a parking lot and too much for 25-35 mph roads but seemed OK on the highways. But it was not enough, it was causing the truck to use more breaking power than the trailer. Also control your speed on big down hills switching between gears and breaks.

The breaking power of the trailer needs to be close to equal of the truck at highway speeds (the trailer should not be pushing the truck and the truck should not be pulling the trailer under breaking). For me now at highway speeds I turn my break controller up to like 10 -12 on my Techonca P3. However, once off of highway speeds you need to turn down the breaking power or you will feel the trailer breaks trying to stop you especially in town or parking lots. You have to play with it a bit to dial it in for your needs. My settings may not work for anyone else but the theory will work.

Do not be afraid of some RPMs. I will down shift to 4-3 or maybe 2 depending on the situation. I try to keep the motor turning about 3000 rpm. As it gains speed and approaches 4000 rpm I break gently until I am back to 3000 rpm. My theory is this is allowing some break cooling as the motor takes the load and vice a versa.
Hope my experience helps. This has been working for me.
If you do not have the TRD rear sway bar you may want to consider one, also adding a cabin controlled rear air bag over load suspension, together makes a huge difference in the way the Tundra will tow.
 

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I am no expert on this subject, so I am pointing that out right up front.
You should NOT be using cruse control and expecting it to control your speed on down hills with a trailer. Use your gears in combination with your brakes. You do not want to over heat your breaks and lose them. I do not know what brake controller you have and some are not well thought of. I have a 26 ft Airstream. I drive almost solely on mountain roads. I did not have my brake controller turned up enough many times but unaware. Once on a very mountains road driving too fast I over heated the brakes on the truck and lost breaking power. My fault and very scary.

That event caused me to learn more about my brake controller. I talked to people that I trusted with more experience towing than I had. I was told you need to change your controller setting for the situation. I usually left it in one power setting for just about everything. I was running it on the highway at 7.8 (comparable to volts, 0 volts is no electric breaking power on the trailer and 12 volts would be a lot although some break controllers will go beyond 12 volts). For me 7.8 was too much breaking driving around a parking lot and too much for 25-35 mph roads but seemed OK on the highways. But it was not enough, it was causing the truck to use more breaking power than the trailer. Also control your speed on big down hills switching between gears and breaks.

The breaking power of the trailer needs to be close to equal of the truck at highway speeds (the trailer should not be pushing the truck and the truck should not be pulling the trailer under breaking). For me now at highway speeds I turn my break controller up to like 10 -12 on my Techonca P3. However, once off of highway speeds you need to turn down the breaking power or you will feel the trailer breaks trying to stop you especially in town or parking lots. You have to play with it a bit to dial it in for your needs. My settings may not work for anyone else but the theory will work.

Do not be afraid of some RPMs. I will down shift to 4-3 or maybe 2 depending on the situation. I try to keep the motor turning about 3000 rpm. As it gains speed and approaches 4000 rpm I break gently until I am back to 3000 rpm. My theory is this is allowing some break cooling as the motor takes the load and vice a versa.
Hope my experience helps. This has been working for me.
If you do not have the TRD rear sway bar you may want to consider one, also adding a cabin controlled rear air bag over load suspension, together makes a huge difference in the way the Tundra will tow.
I am no expert on this subject, so I am pointing that out right up front.
You should NOT be using cruse control and expecting it to control your speed on down hills with a trailer. Use your gears in combination with your brakes. You do not want to over heat your breaks and lose them. I do not know what brake controller you have and some are not well thought of. I have a 26 ft Airstream. I drive almost solely on mountain roads. I did not have my brake controller turned up enough many times but unaware. Once on a very mountains road driving too fast I over heated the brakes on the truck and lost breaking power. My fault and very scary.

That event caused me to learn more about my brake controller. I talked to people that I trusted with more experience towing than I had. I was told you need to change your controller setting for the situation. I usually left it in one power setting for just about everything. I was running it on the highway at 7.8 (comparable to volts, 0 volts is no electric breaking power on the trailer and 12 volts would be a lot although some break controllers will go beyond 12 volts). For me 7.8 was too much breaking driving around a parking lot and too much for 25-35 mph roads but seemed OK on the highways. But it was not enough, it was causing the truck to use more breaking power than the trailer. Also control your speed on big down hills switching between gears and breaks.

The breaking power of the trailer needs to be close to equal of the truck at highway speeds (the trailer should not be pushing the truck and the truck should not be pulling the trailer under breaking). For me now at highway speeds I turn my break controller up to like 10 -12 on my Techonca P3. However, once off of highway speeds you need to turn down the breaking power or you will feel the trailer breaks trying to stop you especially in town or parking lots. You have to play with it a bit to dial it in for your needs. My settings may not work for anyone else but the theory will work.

Do not be afraid of some RPMs. I will down shift to 4-3 or maybe 2 depending on the situation. I try to keep the motor turning about 3000 rpm. As it gains speed and approaches 4000 rpm I break gently until I am back to 3000 rpm. My theory is this is allowing some break cooling as the motor takes the load and vice a versa.
Hope my experience helps. This has been working for me.
If you do not have the TRD rear sway bar you may want to consider one, also adding a cabin controlled rear air bag over load suspension, together makes a huge difference in the way the Tundra will tow.
Thank you so much!

I know this is a big ask, but would you be willing to talk over the phone? It'll help me process the info better as ill be able to sort through all the technical language.
 

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Thank you so much!

I know this is a big ask, but would you be willing to talk over the phone? It'll help me process the info better as ill be able to sort through all the technical language.
Check your private messages section.
 

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Also know that the tow haul mode is designed to work the engine downshifting, however it won’t engage until you tap the breaks if you are tapping them to late that could also be the problem. Next hopefully tow haul is working properly. Also as everyone says depending on the grade you will always be picking up speed somewhat.
 

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Trailer brake battery? The brakes are powered from the tow vehicle. Otherwise yes... Make sure brakes are adjusted properly and they should keep the braking on the truck close to normal...

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You truck can handle this weight. If you get a bigger truck, like a diesel or 1 ton truck, those trucks will have more engine torque (especially diesel trucks) and may have steeper rear end gears, or both, which will provide more engine braking. But we are not talking about a huge difference. Maybe no difference at all, especially if you are talking about a gas engine of roughly the same size as your 5.7L. I have pulled big trailers with a Tundra with the 4.7L, 4.6L, and 5.7L, as well as a Ford F-150 with the 4.6L and 5.4L, and a half ton chevy and a couple Suburbans with the 5.3L, and a 3/4T Chevy Crew Cab with a 350. As far as pulling goes, all these all pull roughly the same.

The most important thing is to slow down. You cannot drive steep hills up or down at regular speed like you are driving a car. You have to slow down and take your time.

If you are going down a steep grade, you should down shift the transmission and let it eat. It may seem like it is really revving up too high, but as long as you are below the red line of the engine, you are not doing any harm, so just let it eat. You may need to slow down some as well because the lower the gear you are in, the more brake power you get from the engine. You may find you need to be in first or second gear to hold back a big trailer on a steep hill, and that may limit you to 20-30 mph, but so be it. You should really try not to use your brakes much on a downhill drive. Just take it slow and let the engine do the work. You should always try to adjust you downhill speed so that the engine can hold it back without using the brakes.

On a very steep grades, the truck engine will not hold it back, even in first gear, and when that is the case, you are going to have to use your brakes. The proper way to brake going down hill is to use the brakes fairly hard so you slow down until you are below your desired max speed, then take your foot all the way off the brakes and let them cool while the truck speeds up again, when you are at you max desired speed, use your brakes again. The main thing is that you want to be on, then off, then on, then off so you let those brakes cool down. If you just hold the brake on, even lightly, you will over heat them and lose the brakes. If you are on a hill that is too steep for the engine to hold it back, that should mean you are in first gear and the truck is still gaining speed. And when that is the case, your max speed should be determined by the engine RPM. If you are in first gear and still gaining speed, let the engine go up as far as you are comfortable (maybe 5000 RPM), then brake down to maybe 2500 RPM, the let off the brake and let it speed up again to 5000 RPM, and repeat.

And yes, you need to have a good balance between the truck brakes and trailer brakes. They should be adjusted so that the trailer brakes take care of the trailer, and the truck brakes take care of the truck. You should not have to push your brake pedal much harder than normal to stop with a trailer on. If you do, turn up the brake controller until the brake controller is able to stop the trailer.

Last, if people are blowing by you with a trailer, don't sweat it. Those are the guys you will meet at the campground that have been there two weeks waiting for their transmission to be rebuilt because they burned it up driving like a Ferrari.
 
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