I have a 2007 Tundra 5.7L 4x2 Dbl Cab with 4.3 differential. When I tow my travel trailer weighing about 7200 lbs and very little in the truck bed, the truck downshifts on every hill regardless of how small the hill. With a tow capacity of 10,600 lbs, this weight is well within the truck's rated capacity. This does not seem normal to me. Is it? Is it bad for the transmission or differential?
Your trailer is pretty heavy. Are you using the Tow/Haul mode? Tow/Haul mode will keep the RPM's up to power over a hill, especially if you have the cruise set. Your Tundra doesn't know how big or long the pull will be so, it's going to prepare itself for a hard pull.
Without Tow/Haul mode engaged, you are going to get a lot of up and down shifts all the time.
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2007 Toyota Tundra Double Cab SR5 with the 5.7L V-8 and Doug Thorley headers
"Trying to tax yourself into prosperity is like standing in a bucket and trying to pick yourself up by the handle." - Winston Churchill?
6 gears are alot to play with. It knows what gear to be in under normal circumstances with no load. Then when you tow if you're still giving it easy access to the higher gears rather than telling it to hold for longer that's 1-2 more shifts it has to do when terrain changes.
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09 Crewmax 4x4 5.7.
Stampede bug deflector/ventvisors
Matching front tint.
Pioneer PRemier DEH 980BT
Pioneer Premier Shallowmount 10
Hertz HSK165.
Eclipse rear coaxials.
Eclipse EA4200/Alpine MRP M500
I have a 2007 Tundra 5.7L 4x2 Dbl Cab with 4.3 differential. When I tow my travel trailer weighing about 7200 lbs and very little in the truck bed, the truck downshifts on every hill regardless of how small the hill. With a tow capacity of 10,600 lbs, this weight is well within the truck's rated capacity. This does not seem normal to me. Is it? Is it bad for the transmission or differential?
I appreciate any info on this.
If you use D-mode and not sequential mode it will downshift when you touch the brakes. It is perfectly normal; and it helps to reduce braking. When in either mode D or S; with the cruise set it will downshift as well if your speed goes over 5mph from the set point.
I don't think it's bad for the trans or diff, but it does see additional wear from it. I personally, don't like it so i usally tow in S mode most of the time and shift manually going down hill. Otherwise, it's best to use D mode with the T-H mode enabled when towing.
Where you're using the truck for towing, just be sure to have the diffs and trans serviced sooner than normal and you'll have no problems.
How fast are you going and what gear is it down shifting to?
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Beer please! CBTMA (Member and Founding Father: Est. August 15, 2008)
Clicky>>> What The Heck is CBTMA
Unknown - "The biological purpose of pain is to prevent the recurrence of stupidity."
I try to hold it between 58 & 60. I downshifts to 5th, then 4th. I am new to towing a heavy trailer like this, so I guess I need to learn to use the S-mode. I had not read about it until now.
I try to hold it between 58 & 60. I downshifts to 5th, then 4th. I am new to towing a heavy trailer like this, so I guess I need to learn to use the S-mode. I had not read about it until now.
Completely normal.
5th and 6th are both overdrive.
I tow a 5000# TT with a flat front, at those speeds, mine mostly stays in 5th...unless I get a nice flat section of road (not many of those in the PNW) or I'm going down hill.
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Beer please! CBTMA (Member and Founding Father: Est. August 15, 2008)
Clicky>>> What The Heck is CBTMA
Unknown - "The biological purpose of pain is to prevent the recurrence of stupidity."
Personally, I only use it when my truck is really hunting for gears...like every few seconds in really hilly terrain. I'll use it in S-5 to lock out 6th.
Typically I just use D with the tow/haul on and the truck is perfectly happy.
Play with it next time you are towing, you ain't gonna hurt anything and you'll learn where your and your truck's comfort zones are.
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Beer please! CBTMA (Member and Founding Father: Est. August 15, 2008)
Clicky>>> What The Heck is CBTMA
Unknown - "The biological purpose of pain is to prevent the recurrence of stupidity."
If you are an engineer, you should appreciate these. Lots of pages, I know, but tons of great information and answered questions.
Give em' a read then send beer.
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Beer please! CBTMA (Member and Founding Father: Est. August 15, 2008)
Clicky>>> What The Heck is CBTMA
Unknown - "The biological purpose of pain is to prevent the recurrence of stupidity."
The only reason I have the Tundy is to pull the boat. I hate the down shifting. I use S4 or S5 depending on hills or wind. At 58 to 60 mph, and 7200 lbs I would use S4, set the cruise and enjoy the ride.
The only reason I have the Tundy is to pull the boat. I hate the down shifting. I use S4 or S5 depending on hills or wind. At 58 to 60 mph, and 7200 lbs I would use S4, set the cruise and enjoy the ride.
Really?? That's my favorite part about towing with the Tundra, saves a lot of heat on the brakes.
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2007 Tundra 5.7 6-spd 2wd
Silver, double cab, short bed
TRD package
Tundra downshifting towing travel trailer
I hate the down shifting. I use S4 or S5 depending on hills or wind. At 58 to 60 mph, and 7200 lbs I would use S4, set the cruise and enjoy the ride.
Linear Mode
