Hank-buford

Im just curious when I should use my tow/haul switch. Is it safe to leave it engaged while driving at highway speeds? Thanks

Eric0508

Yes it is safe. Use it anytime you hault a trailer/load of any significant weight. It doesn't affect fuel economy in any significant way and may save your transmission

SIC_HDPP

I'm going to have to disagree with you on some points. Tow haul mod holds gears longer and unlocks the torque converter more often resulting in higher rpm's which means more fuel used.

Personally scooting around I use tow haul for the stop and go traffic. On the express ways (ones that aren't extremely hilly) I don't have tow/haul on. If the truck is constantly shifting between sixth and fifth I will lock out sixth and run I'm fifth gear with no problems.

acadianbob

Partially true. It doesn't lock the torque converter until 4th gear when normally it would lock in 3rd. This is done to provide more "oomph" when accelerating. BUT, at highway speeds, it will shift to 5th (if it needs more RPM due to load) and remain locked whereas the normal process is to stay in 6th and unlock the torque converter. Fuel use difference is negligable.

smokeywren

I can't tell any difference when tow/haul is engaged unless towing heavy in hills or mountains. The big difference when towing heavy in hills and mountains is the gear selection strategy. It will downshift much earlier for comin' down the mountain, and automagically downshift all the way down to 2nd gear if necessary to control the speed. Without tow/haul selected it won't downshift nearly as early or as deep into the gear selection.



Yes. Whether towing or hauling or not, you can drive at normal highway speeds while tow/haul is turned on, even higher speeds such as 84 MPH ticket limit on I-10 and I-20 in far west Texas. But you don't gain anything by turning on tow/haul if you're not towing heavy, and I hope you're not towing heavy at over 65 MPH. (Most trailer tires are limited to 65 MPH).

Manuellabour247

I use tow/haul when I'm in heavy traffic hauling any load. Makes it easier to drive. I also use it at the track. lol.

I've used it hauling a 16 ft. utility trailer at highway speeds with no ill effects. You can see it working better when you start off while hauling a load. helps with take-off.

brulaz

This is what I've seen as well. And an unlocked torque converter, especially when pulling a heavy load up a long steady grade, generates more heat which isn't good for the tranny.

I always use Tow/Haul when towing/hauling.

Hank-buford

Cool thanks for the info everyone.