4.0 Tundra pulling with OD or not?

plugnickel · #1 (**permalink**) 03-23-2008, 11:48 AM

We don't have many hills here in TX, unless you get past San Anton or north of it. I usually leave my in OD. IS this in anyone else's opinion, bad for the transmission? We have just bought another Casita travel trailer that is a about 2200 lbs. (dry weight) I would like to here from other V6 people too. Thanks.

Marazzito · #2 (**permalink**) 03-24-2008, 11:56 AM

You more than likely want to take it out of overdrive. Automatic transmissions can quickly overheat when they are constantly shifting back and forth. If you can leave it in OD and it stays in 5th, then it should be safe to tow in OD.

Thelt · #3 (**permalink**) 04-09-2008, 04:11 PM

If it is not constantly shifting in and out of overdrive you should be fine.

funfinder4 · #4 (**permalink**) 04-15-2008, 04:13 PM

Back when we had our little '16 Fun Finder T-160 @ 2,600 lbs, I towed all the time in 5th. The Fun Finders are '7 wide & '9.5 tall...not as aerodynamic as your Casita!

As long as the terrain was level and winds were not high it would stay in 5th gear without any problems. I've noted lower transmission temps while in 5th gear than when I took it out of overdrive (4th gear). As long as the torque converter stays locked, this should be true for you also.

What kind of mileage are you getting while towing? I use to get 11 mpg @ 65-70mph. Once I slowed down to 55 mph following my grandparents Class A and got a whopping 15mpg! Now, I'm lucky to get 9 mpg with my '30 TT.

With all the winds we've been having here lately in East Texas, I've been averaging more like 7mpg!

plugnickel · #5 (**permalink**) 04-15-2008, 08:46 PM

Quote:

Originally Posted by funfinder4

Back when we had our little '16 Fun Finder T-160 @ 2,600 lbs, I towed all the time in 5th. The Fun Finders are '7 wide & '9.5 tall...not as aerodynamic as your Casita!

As long as the terrain was level and winds were not high it would stay in 5th gear without any problems. I've noted lower transmission temps while in 5th gear than when I took it out of overdrive (4th gear). As long as the torque converter stays locked, this should be true for you also.

What kind of mileage are you getting while towing? I use to get 11 mpg @ 65-70mph. Once I slowed down to 55 mph following my grandparents Class A and got a whopping 15mpg! Now, I'm lucky to get 9 mpg with my '30 TT.

With all the winds we've been having here lately in East Texas, I've been averaging more like 7mpg!

I have been getting about 14 in OT. (5th gear) It is about 14 out of OT.

zeropoe · #6 (**permalink**) 04-23-2008, 08:19 PM

why is Overdrive the default position on my tundra always hauling 2000 or 3500 pounda and have to turn off overdrive but can't tell the difference between on or off should I only use overdrive on the highway. I also was wondering what the maintenance required light would flash five or six times and turn off. I have an 06 V8 Tundra longbed automatic. Some advice for a landscaper out there?

funfinder4 · #7 (**permalink**) 04-23-2008, 08:43 PM

Quote:

Originally Posted by zeropoe

why is Overdrive the default position on my tundra always hauling 2000 or 3500 pounda and have to turn off overdrive but can't tell the difference between on or off should I only use overdrive on the highway. I also was wondering what the maintenance required light would flash five or six times and turn off. I have an 06 V8 Tundra longbed automatic. Some advice for a landscaper out there?

For most landscaper's I'd suggest turning O/D OFF if your not on the highway. For everyday city street towing, you speed is generally going to be ~40mph... which is ok for 5th gear non towing... but to low in rpms if towing. That's probably why you don't really notice a difference right now, because most of the time it's staying in 4th gear or lower. Turning O/D OFF will insure it doesn't try to shift into 5th for those very short periods of time possibly while going down small hills.

Matinance required light is an oil change reminder. Easy to reset if you've changed your oil but just didn't reset the light. Hold down the trip selector while you turn the key to "on"... Hold trip until you see your OD count down. Light should go out. Do change your oil though if it's time.

kathyricks · #8 (**permalink**) 04-24-2008, 01:03 AM

Americans are conditioned to think high RPM is harmful to engines because they were raised around slow turning pushrod American V6 and V8 engines that would wear fast or suffer burned valves if run at high rpm all day long.

Asian engines are different. They can run 3000 - 4000 RPM all day long for 500,000+ miles. They've doing it since 1975. But Americans are reluctant to believe this so thousands of them tow in overdrive and end up burning up their transmissions.

Anyway, the rule of thumb is that it's OK to tow in overdrive IF you are sure the torque
converter clutch is not constantly unlocking and locking (watch the tachometer) and IF the transmission is not constantly shifting in and out of overdrive. For owners who can't tell what the transmission is doing then lock it out of overdrive. Your Asian engine and transmission will thank you with a long, troublefree life.