When to use Tow/Haul mode?
 

Ok, so this past weekend I pulled a trailer for the first time with my fairly new truck. Yeah, I know, another grocery getter pretending to be a man. [dummy] What can I say, times are tough and I'm not able to move forward with my plan right now to purchase or even sometimes rent a toy hauler.

So, my buddies and I loaded up our dirt bikes, gear, fuel, water, tools, etc., for a long day at a local MX track. My friend's trailer is a home built unit, but very sturdy and big. He said it weighs about 1500 pounds empty. He drives rigs for UPS, so I'm sure he is knows the weight of the trailer to be correct.

Anyways, I asked him and he did some quick math and figures we were pulling about 3,000 to 4,000 pounds. No challenge for the truck really. But, it had me wondering. When is the right time to use the Tow/Haul mode?

We were on freeways, about 1.5 hours each way, mostly flat ground.

Oh yeah, I averaged about 16 mpg with the load too. Awesome!!! [guitar] Try that with a gasoline truck.

ben

this is just my opinion but I use tow haul anytime I pull a trailer.
most of the loads I haul are pretty heavy though.
I wish I got 16 mps empty.
When I pull the 48 foot enclosed I get around 9 or 8 if there is a head wind.

my truck is a 2004.5 which means I have OD lockout. I use OD lockout in the mountains to keep rpm above 1800 when traveling at slower speeds. For these trucks 1800 rpm are above keeps from lugging the truck. Cooler egts and you are in the power band so to speak.

I use tow haul whenever I pull a trailer. And the heaviest thing I pull is a 25 foot pontoon boat. About 5000 lbs. It may be overkill but I don't want my transmission life to be a fair fight. I have a mag h tranny pan and diff cover. Most of the lakes I go to are a long way down twisty, two lane, hill laden roads. I got tired of putting transmissions and rear gears in 1/2 ton trucks and went heavy duty. So what if it's overkill, use it. Nobody on this site will give you any grief for taking steps to extend your parts life.

I use tow haul all the time with the 6.7 and the 68rfe transmission. If you still have your emissions in place it helps to keep the rmps up and not lug the beast in town driving. I have clocked over 35000 miles with no soot or emissions problems. I run the exhaust brake and tow haul all the time weather hauling anything or not. It will not affect your highway mpg at all but it will lower your city mpg just a bit.

I agree with the above, plus it helps bring it to a stop with less foot braking.

Also sounds cool.

Chris

I use T/H accelerating and hill climbing on the open road. I rarely use T/H in town or on downhills. I like to shift for myself, and the automatic downshifting in T/H with the EB, usually doesn't match my needs exactly for the moment.

I use mine all the time, and have not noticed any difference in my MPG. I like the added throttle response.

Same here.

the thing that is different about the 68rfe and the 48 is that the TH mode does more than just lock out O.D., it actually changes the shift up and shift down points giving you better resonse and better braking. The 68 has a tendancy to lug around when in normal mode and that creates trans heat. When it is in TH it has much higher shifts and they are much crisper both up and down. It also holds the engine brake engaged alot longer.
I drive around town in TH sometimes if the trafficis bad just to let the EB do its thing better, also anytime I have a trailer hooked up

Chris

I have an 03 and I tow with in O/D as long as you have the rpms up up high enough that when you push the O/D on button it dosent lug down to low, Lugging down in O/D while towing is hard on the Little spur gear in the tranny. If its a steep hill I will kick it out of O/D.

Wow. I didn't realize so many of you would recommend running in TH not matter what you are towing, and especially didn't expect you recommend it when empty.

I've tried it and liked the better throttle response and EB action, but figured it would be worse on mpg's that way too.

Ok, so now I have two buttons to push everytime I startup. EB and TH. LOL

Thanks for the responses.

ben

With my '05 I always use TH when towing my 6K boat or 10K school band trailer. While I can't lock out OD, if I cycle the TH switch between TH and not-TH and back to TH the trans will drop out of OD. It'll stay out till the hill drops away and then shifts back up to OD. Maybe this is a feature of my BD valve body, but I like it in the absence of an OD lockout.

The double deep transmission pan was a good investment along with the valve body. I had the truck at the dealer for a look see and the mechanic commented on how firmly it shifted.

I ran this weekend in TH mode. First day was loaded with my dirt bike and gear. Nothing heavy at all. Next day empty.

Man it is so much more jerky when slowing down. Practically don't have to use the brakes. But, I worry about what all that jerking is doing to the tranny and driveline. I didn't tell my wife, and she started bitching at me for driving crazy. LOL

ben

I wouldnt think it is doing any more to the powertrain than it would be when you are towing heavy and using TH.