Matt_Jr
Platinum Member
bake321 said:
Sounds like a heck of a drive. Listen to books on tape, satelite radio, or sing
100 bottles of beer on the wall w/the kids?Should I Be Using Overdrive When Towing?
- Thread starter Rameck
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Sounds like a heck of a drive. Listen to books on tape, satelite radio, or sing
100 bottles of beer on the wall w/the kids?Best to read the owners manual. Unless the vehicle has a lot of torque/horsepower to spare in overdrive (and many SUV/trucks are overpowered these days compared to their predecessors) - you typically don't want to be in overdrive when towing. Overdrive is meant for fuel efficiency at constant speed on flat surfaces. It is not meant for quick accelerations or pulling heavy loads.
Joe
Joe
Builder
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Know your transmission. Find out which gears will lock the torque converter, too!
Matt_Jr
Platinum Member
Builder said:
Many cars and trucks will lock the torque converter at speeds as low as 25mph depending on engine load i.e. coasting, maintaining speed and slight acceleration on level roads. However not all owner's manuals will tell you when the converter will lock and often times the only way to know is to look it up in the service manual or on a scan tool while watching the vehicles data stream. I know I know, lots of people keep saying read the owner's manual and there's nothing wrong with that. The fact is that the owner's manual is written to help you understand how to properly operate your vehicle in most conditions, but it doesn't go into descriptions of how things work and break down what to do to often help you get the most out of it.
For instance, I know a lot of people who would never think to shift a vehicle into a lower gear while going down a steep hill and pulling a load in an automatic transmission. This can save a lot of wear on your brakes and decrease the chances of glazing the pads and rotors and boiling the brake fluid while maintaining control. It might increase a little bit of wear on the trans but I do it in every car and truck I own. I've put almost 150K on one truck, 130K on a car I have, 140 on 2 suburbans and several others and have yet to burn up a transmission. And I do this every single day. I live up on a mountain in northern Va. 2 miles off the paved road on hills that require four wheel drive in dry weather if towing even something as light as a small atv.
The key to making your truck last long is regular preventive maint. I flush my trans with BG synthetic fluid every 25k miles and drive close to 100k miles a year. My Toyota Prius has over 130k miles on it and still has the original brakes on it. My rotors are starting to rust more than my brakes are wearing out. I'll have to replace those when it does finally need brakes but the point I'm making is the more you know how they work the longer you can make them last by having good driving habits that help them work better, more efficiently, and last longer. That includes knowing when to push the tow/haul button, when to turn off the overdrive, and when to pull the shifter down into 3rd, 2nd, 1st, or straight from drive to first. On vehicles with automatic transmissions built after '95, you don't have to worry about overreving the engine 'cause the computer won't let you (unless you're in first and accelerating). Practice leads to confidence which leads to competence, even in something as mundane as pushing a button. I'm going to shut up now.
OP
Rameck
Bronze Member
This is a 2001 Tundra extra cab with a V8 but don't know the cu. in. of the engine. There is no haul mode switch for this that I'm aware of. The hitch is after market. I figured that I'd not be using the OD for up and down hills but some flat land between L.A. and upper Ca. was wondering if usable on the flat areas. The speed is posted max of 55 mph for towing trailers in Ca. and that's fine with me. I feel more comfortable and more in control at lower speeds towing this big of load. Figure, by the time I get to tow it to Washington this summer, gas will be around $4.00 a gal. but don't want to ruin the trans just to safe some money on the flats using overdrive when towing. Appreciate all the input. Still learning.
thanks,
Ralph
thanks,
Ralph
Matt_Jr said:For instance, I know a lot of people who would never think to shift a vehicle into a lower gear while going down a steep hill and pulling a load in an automatic transmission. This can save a lot of wear on your brakes and decrease the chances of glazing the pads and rotors and boiling the brake fluid while maintaining control. It might increase a little bit of wear on the trans but I do it in every car and truck I own. I've put almost 150K on one truck, 130K on a car I have, 140 on 2 suburbans and several others and have yet to burn up a transmission. And I do this every single day. I live up on a mountain in northern Va. 2 miles off the paved road on hills that require four wheel drive in dry weather if towing even something as light as a small atv.
Actually, when in T/H a quick tap on the brake peddle while going down hill tells the trans controller that it should maintain that speed. It down shifts to hold that speed - all by it's self. Works real good - surprisingly so. Then again, that's a GM and not a Toyota so maybe that capability does not cross over?
For the OP - if you don't have a T/H button - I'd agree you are much safer manually sticking it in D and not OD. But on the flats you could probably give it a go with little to no down side. Just don't forget to flip it back to D on uphill grades or to pass.
If you have not be doing regular trans fluid flush's on the truck, I would 100% do it before the tow. Your truck will thank you for it! Power back flush, new filter and if you can $$ go with synthetic fluid. I'd also put synthetic gear oil in the rear differential as towing will heat them up.
jb
Egon
Epic Contributor
Uhh, does your truck have a larger transmission cooler on it like comes with some vehicles that are configured for towing?? If not stay out of overdrive.
When I tow with my truck the OD is always locked out.
When I tow with my truck the OD is always locked out.
Builder
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john_bud said:
My light truck actually has a feature where you pull the shifter stalk back one notch to the "M" (manual) position and then you can push the "+/-" toggle switch on the shift stalk and shift it like a manual transmission with no clutch. Of course, in tow haul it downshifts automatically.
HarryVanderpool
Gold Member
So far, everyone has left out a very importand part of the equation:
What is your final drive ratio?
My 7.3 PSD has a 4:88 final drive.
I tow 8800# all over Oregon in overdrive.
If i didn't, I would have to push 2500 rpm just to reach 50 mph.
When I'm on slow windy roads I lock out OD.
Otherwise, its just another gear.
I cruise at 2000 RPM which is 54 mph. (in OD)
What is your final drive ratio?
My 7.3 PSD has a 4:88 final drive.
I tow 8800# all over Oregon in overdrive.
If i didn't, I would have to push 2500 rpm just to reach 50 mph.
When I'm on slow windy roads I lock out OD.
Otherwise, its just another gear.
I cruise at 2000 RPM which is 54 mph. (in OD)
Builder said:
Yeah, that is a super nice feature on the newer 6 spd allisons. My archaic 5 speed alli could use that and the 2nd OD!
Harry, 2000 rpm at 54 mph??? Ouch! And you only tow 8800# with it? Double ouch! I used to tow that much with my yr 2000 1/2 ton auto 3.73 gears and got 10-11 mpg. BUT.... Taxconsin is mostly a good bit flatter than Oregon. While expensive to run, I'll bet it's a stable rig.
jb
