New TT. the last one was very heavy, so od off, no brainer but this one is very light, and when towing, I stuck at 2,700 rpm most of the time except for hills, when it hit the passing gear. Not a lot of weird "hunting" rpms going up and down....I know the od is not a power gear, I dont want to hurt my tranny, but Id like to stay in od if its safe, im sure it saves gas...but then again I got 10 with the overdrive on, so I guess I just like the fact that with od on the rpm's are lower, seems nicer to the engine. I dont know, im not an engineer. :-{
Hi, first thing would be to read your owners manual and see what it says. Mine says it's OK to tow in overdrive. But when hitting hills, up or down, I manually turn off overdrive and manually down shift to a proper gear. Some later vehicles have a TOW/HAUL mode and will down shift automatically for up-grades or down grades.
Bob
2005 Airstream Safari 25-B
2000 Lincoln Navigator
Equal-i-zer
Yamaha 2400
for one thing going into passing gear may not be the best gear for towing up a hill. third gear would be better and ease off the foot pedal a little bit, no need to push your rig up hill as fast as you drive on the flat
If it says you are ok to tow in od, then you can, although you probably want to experiment. My Tahoe says I can tow that way too, but I actually get better fuel economy towing in 3rd, and the transmission temperature runs about 10 degrees cooler. The engine seems more efficient in the 2300-2500 rpm range than at 1800 rpm when under heavy load.
Quote: I just like the fact that with od on the rpm's are lower, seems nicer to the engine
But your trans temp fluid does not. Check your owners manual. Bear in mind the slower you go under a load the less the fluid is getting cooled. Trans temp is a killer of trans.
Lower rmp also means less fluid pressure and some transmissions need higher pressure to operate right under loads. Your choice where to put your money, fuel tank or trans.
My brother in law jumps up and down with joy that he gets 2 more mpg than I do when we go camping with our trailers. He pulls their trailer at 65-70 and OH YA lets see. He has had several blow outs burned up 2 sets of trailer bearings (he never re-packs them) and blown up a turbo one time, and a trans one time, and can't get over 20,000 on brakes and has had 3 minor accidents in the last 5 years and his truck is one year newer than mine.
Your choice
(To cheap to buy new)
1990 37 ft 5th wheel that hasn't moved since 1996 (our best home)
1997 33 ft trailer (winter home in much warmer climate)
2005 25 ft M/H (our "stand up B" for traveling)
nrg2brn wrote: ...when towing, I stuck at 2,700 rpm most of the time except for hills, when it hit the passing gear.
This quote concerns me. What is your tow vehicle and what transmission?!
I'm going to assume a 4spd trans, so 3rd is the 'passing gear'. Your either going pretty fast or your not getting torque convertor lock up in 4th (OD) so your generating a lot of heat. TC lock up can be determined by modulating your foot on the throttle; do you get a change in engine speed without any (or a small amount) of change in vehicle speed? If so then the TC is not locked and generating heat; lock out OD and tow in 3rd.
The same would apply if you have a 5spd trans, but the above is an example.
2005 2500 Cummins/48RE/3.73, QCLB, 4wd, BigHorn, Edge Juice w/ CTS + Turbo Timer, ISSPro Oil and LP pressure gauges in cubby hole, GDP 20/2 filters on frame rail, Custom Diesel Steering Box Brace
'10 Forest River Shockwave Toy Hauler 21'
Honda EU3000I Genny
I don’t use OD never have, and if I had a newer TV that said I could I still wouldn’t…
I travel at about 62 and not using OD has kept my engine and tranny working like new for 200,000 miles now… lower RPMs doesn’t equate easier on the engine or better MPG…
I have never heard of anyone doing harm by not using it…
Love my mass produced, entry level, built by Lazy American Workers, Hornet
My truck has an automatic transmission controlled by a computer so I have no need to manually do anything. I could NEVER monitor all of the parameters the computer monitors to make that decision. I DO decide if I want to use tow/haul or leave the tranny in normal driving mode. I usually make that decision when I hitch up the trailer.
Good luck / Skip
2011 F-150 HD Ecoboost 3.5 V6. 2550 payload, 17,100 GCVWR - 2004 F-150 HD (Traded after 80,000 towing miles) 2007 Rockwood 8314SS 34' travel trailer
US Govt survey shows three out of four people make up 75% of the total population
If the road is flat or even better, slightly downhill, the tranny is not "hunting" and my trans fluid temps are where they belong I will run in OD as it is simply more efficient. Using 500 less rpm for the same speed will positively impact your mileage but..... anytime the downhill grade gets to be more than about 2 percent I lock out OD to maintain a safe, controlled speed without riding the brakes. If the grade going up is enough to cause the tranny to downshift then you should lock out OD to keep it from hunting which will generate excess heat.
We have been doing a lot commuting with just the TV up to the mountains where we parked the TT for the summer. I love to lockout OD on the mild down grades as it will hold my speed at a very comfortable level without the use/abuse of the brakes. If the grade gets steeper, about 4 percent or more, then I just manually downshift to 2 which will hold me at 50 even on a 6 percent grade and the brakes stay nice and cool ready for any emergency.
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Hi, first thing would be to read your owners manual and see what it says. Mine says it's OK to tow in overdrive. But when hitting hills, up or down, I manually turn off overdrive and manually down shift to a proper gear. Some later vehicles have a TOW/HAUL mode and will down shift automatically for up-grades or down grades.
