tow 4000lbs without tow/hall
 

2007 5.9 with 68,000 and runs great had all fluids done but dont know if when i tow my 4000lbs camper if i need to tow on flat land in tow/hall mode all the time. THANKS for any advice Tom

I'd say no for 4000lbs. As long as the transmission isn't hunting around trying to find the right gear you should be just fine towing in OD, tow haul not required

Depends on the terrain and type of driving you're doing. I've found it more efficient to run in tow/haUl if I'm under 50mph in hilly areas or a lot of slow down speed up type driving. Tow haUl will lock up the torque converter a little over 30mph in 3rd gear depending on throttle and keep from running up against the loose factory converter as much. It also keeps the tranny temp cooler.

I've got 117K miles and never had any problems with my CTD trans; however, my neighbor, who owns a transmission shop, has always told me that running in tow/haul mode will likely make my tranny last longer. And since adding my Smarty four years ago I leave mine in TH most all the time.

Thanks
 

Thanks for the info and i did not know if in t/h mode if it burns much more fuel.

Although I've heard people say you won't get as good of fuel mileage running in TH, the difference (for me) has been almost negligible. Depending on the terrain, I think TH can add mpg's if used accordingly. But I figure if my tranny will last longer then it would probably offset any additional fuel costs.

I tow an 8k+ Airstream trailer with mine. I usually use the tow/haul mode but often forget. No problem on my end so you can easily get by with it or without it.

I tow a 5500lb 32' gooseneck trailer with 2 cars inside using OD 95% of the time. For me, it is speed dependent - if a hill is making me loose MPH with out much increased pedal position, I will hit the Tow Haul which puts me into "D". I like to switch into D without the tranny doing it because it really raises the RPMs when it does itself. Also starting out from a dead stop, I use tow haul until 60 mph at which time I let off the pedal, push the button for OD, and the truck shifts very smooth and easy into OD, then I get back on the pedal. Just my two cents of being kind to the truck and tranny. Last trip put me over 202K miles - stock tranny with Goered Torque Convertor.

In flat land I do not think it will make much difference in mpg unless you stop and start a whole lot. In slow, mountainous country I run T/H even when I am not towing. On the 2007 you are in the same top gear whether in T/H or not on the flat.

When I had my v6 Chevy I got my best gas mileage in tow/haul, maintaining just enough speed to keep it in OD, with an open road in front of me. Your results may vary.

Just remember.... people will give different responses based on the different year model of thruck they own... Tow/Haul performed different functions on different year models.
Your 07 should operate the same as my 06, tap tow/haul once and the only thing changed is the shift schedule and how quickly the converter goes to lockup after a gear change, also backshifts the trnas with converter lock on decelleration..... tap it again and it completely disengages the Overdrive unit, leaving only 1,2,and 3 gear. Tap it yet again and it goes back to the normal driving mode.
I believe in either 04.5 or 05, the Tow/Haul button performed different functions. Seems like some years the Tow/Haul simply disengaged the OD unit....
I can say that at 4K lbs.... you are ok pulling in any mode you wish... unless you have really oversized tires and grocery getter gears

Poormanscat has it right.

For the 06-07 run it in TH all the time. It shouldn't be mpg you put priority on but rather the life of the tranny (and mpg is negligible at best considering other uncontrollable factors like terrain and wind). The TH mode on 06-07 trucks makes it a no brainer. If you don't have a tranny temp gauge I would be especially concerned with taking are of it. While on flat lands you don't have hills and gravity to contend with, you will have cross and headwinds. The truck is as aerodynamic as a 4x8 sheet of plywood. Winds will make the truck/tranny work hard. If you can't see your tranny getting hot so you can back it off, err on the side of caution and run TH to utilize the benefit it provides.

In TH the TC locks up right around 30mph, 4th and OD lock in right around 50mph. Upon decel the TC stays locked until around 20-25mph. I use TH exclusively, city, highway, loaded or unloaded.

I would like to see a message describing exactly what TH does in each year of truck. I think my 2005 just shifts harder and at different RPM's in TH as compared to regular.


47

Does your 05 go into OD when TH is engaged?

'07 48RE does. Just at a higher RPM and MPH. I think around 65MPH.