Thread Tools Search this Thread Display Modes
Old 01-06-2010, 12:12 PM   #1
2 Rivet Member
mddsmith's Avatar
2002 27' Safari
College Station , Texas
Join Date: Oct 2009
Posts: 58
Why shouldn't I use overdrive?

It's been a while since my last dumb beginner's question, so here goes. My tow vehicle is a 2005 Ford F-150 with a 5.4L V-8, with a tow rating or 8000 pounds. My trailer has an empty weight of 5300 and max weight of 7300 pounds. (I know this is not the optimum tow vehicle for this size trailer, but when I bought the truck, I had no idea I would someday be needing it to tow a travel trailer.) I have read that I should disable overdrive when towing a trailer, and Ford has even put a handy little button on the console to accomplish this. My owner's manual just has a brief mention that I should do it, but doesn't give any further explanation. What I'm wondering though is why is this necessary? Would it damage the transmission otherwise, or what?

mddsmith is offline   Reply With Quote
Old 01-06-2010, 12:19 PM   #2
Rivet Master
Lumatic's Avatar

1971 25' Tradewind
1993 34' Excella
Currently Looking...
Estancia , New Mexico
Join Date: Feb 2005
Posts: 6,951
Images: 16
Blog Entries: 1
I have a F250 and a 5.4 Triton. My trailer weighs 4500#. I use overdrive for towing 95% of the time, occassionally switching off the overdrive on long steep hills when I don't want the tranny frequently switching in and out of the high gear. It feels like the most efficient use of the drive train to me. Somebody correct me if I am wrong.

Lumatic is offline   Reply With Quote
Old 01-06-2010, 12:25 PM   #3
Rivet Master
2005 19' Safari
Join Date: Aug 2004
Posts: 2,450
We have a 2008 Tundra that has a "tow/haul mode" switch for the same purpose. However, like you guys, we leave it turned off on the flats; and only turn it on in the mountains when we need engine braking, or the transmissions starts hunting (can't seem to find a good gear and stay in it).

It is supposed to reduce engine lugging, but I think with the new electronic controlled engines and transmissions, that it is best to just let the electronics do their thing, and ignore what the engine and transmission is doing (in most cases).
Phoenix is offline   Reply With Quote
Old 01-06-2010, 12:56 PM   #4
Silver Sneaker
2006 16' Safari
Denver , Colorado
Join Date: May 2006
Posts: 87
Our experiences


1990 Ford F-150 (Overhauled) 302 cu. in. engine, stock transmission (very high speed 4th gear), 06 Bambi 16 (3460 lbs. loaded), full timing (except this winter), just the 2 of us. I only use 4th gear down wind or down hill, 3rd gear 99% of the time.

We also only drive 60ish on busy roads (where others can pass easily), faster on roads where passing is harder, if we can (retired, what's the hurry?).

Someone on this forum had what was a great idea in my mind to determine which gear to use. Get the rig up to a steady highway speed while on the level. Note the position of your foot on the gas pedal. Now, change to the other gear and carefully keep the speed the same and note if you need to push down or let up on the pedal. The position of the pedal is a rough indication of the power needed and gas being used to keep the rig going at that speed. Use the furthest "up" position. Also, usually the further down the pedal is, the harder it is on the engine and gas mileage.

Our bottom line? Slow down, use 3rd gear mostly, use 4th when light. I also keep the RPM at or above 2500; seems like less than that and the engine is struggling too much. Also, slow down, or did I mention that?

Using this method we get around 11.5 MPG (with the trailer), and about 18 without; plus, I expect the engine to last longer.

Happy trails!
Elvie is offline   Reply With Quote
Old 01-06-2010, 01:03 PM   #5
Stefrobrts's Avatar

1968 17' Caravel
Battle Ground , Washington
Join Date: Dec 2002
Posts: 11,979
Images: 50
Blog Entries: 1
I use overdrive unless we're pulling up a long hill. Haven't had any problems that way yet. 1995 E-150 with 351 V8.

Stefrobrts is offline   Reply With Quote
Old 01-06-2010, 01:08 PM   #6
Rivet Master
DanB's Avatar
1970 23' Safari
2005 30' Classic
1986 31' Sovereign
Lorain , Ohio
Join Date: Dec 2005
Posts: 1,633
Images: 9
I have always wondered this myself. A certain retired professional truck driver of this forum can explain it better, but I believe he never uses overdrive.

To me, the engine just sounds like its running easier in overdrive. But, consider the cost. If the engine is running easier, the tranny is working harder. Especially in hills. Going flat, I still don't see a problem. (Rumor has it a certain Durango was spotted doing 90 with trailer in tow.)

In the hills, You can almost feel the tranny getting kicked when it shifts in and out of gear if you are using overdrive. I now understand that it is safer (and less expensive) to tax the engine. I was told "the overdrive gear is the weakest gear".

Just my non-mechanical knowing opinion!
Proud Member of the Wally Byam Airstream Club #24260

The “Ohio Airstreamer -- Informal forum for weekend camping” thread.
DanB is offline   Reply With Quote
Old 01-06-2010, 01:14 PM   #7
Rivet Master
TinLoaf's Avatar
2006 25' Safari SS SE
Trenton , Illinois
Join Date: Feb 2007
Posts: 795
Images: 22
Originally Posted by mddsmith View Post
My tow vehicle is a 2005 Ford F-150 with a 5.4L V-8, with a tow rating or 8000 pounds. My trailer has an empty weight of 5300 and max weight of 7300 pounds. (I know this is not the optimum tow vehicle for this size trailer, but when I bought the truck, I had no idea I would someday be needing it to tow a travel trailer.)
I have the same truck, same engine and almost the same trailer. The truck is actually a really good match for that size trailer and controls the trailer better than my Excursion diesel did. If you install extra gauges you'll see that even though the engine and transmission are spinning faster, the transmission and exhaust temperatures run cooler with the overdrive off. That's all the convincing I needed.
TinLoaf is offline   Reply With Quote
Old 01-06-2010, 01:41 PM   #8
Rivet Master
Jim Foster's Avatar
1965 17' Caravel
1983 27' Excella
Walnut Grove/Laguna Woods , California
Join Date: Jun 2004
Posts: 1,616
Send a message via Yahoo to Jim Foster
The reason for not using overdrive when towing, is that usually when towing, you are driving slower. Slower equals lower RPM, which can equal lower oil pressure in the transmission. If you have a heavy load, and low transmission oil pressure, that combination can cause clutch slippage, which will certainly result in premature transmission failure.

My Silverado owner's manual says to tow in overdrive. That would indicate to me that even at low RPM, that transmission has sufficient oil pressure to not allow clutch slippage. That said, I still shift out of overdrive when the speed drops, and/or the load increases such as going up hill.

That may be "old school", but it works for me, as the truck now has 154K miles and is still doing a good job.
Past President, El Camino Real Unit WBCCI#6620
Street Rod Builder (see avatar)
Kite flier (check out links below)
Jim Foster is offline   Reply With Quote
Old 01-06-2010, 01:57 PM   #9
4 Rivet Member
jump's Avatar
2013 30' International
lubbock , Texas
Join Date: Mar 2007
Posts: 262
2006 3/4 dodge mega cab

Tow-haul mode will keep the trans fluid pumping more truck will downshift in or up shift as it deems necessary by the electronics...if your TV has a Tow-Haul mode, I suggest you use it whenever you are pulling something to keep the trans from overheating...its there for the safety of the transmission, not your comfort.......if you are towing with your 1/2 ton truck, use the overdrive off mode for the same keep the juice flowing and keep the trans cool.

at least this is how I understand how mine works
jump is offline   Reply With Quote
Old 01-06-2010, 02:09 PM   #10
4 Rivet Member
dstalzer's Avatar
2005 25' Classic
Austin , Texas
Join Date: Jun 2008
Posts: 370
It is my understanding that towing in overdrive is ok on level ground, but in hills or mountains, the transmission will continuously be shifting back and forth in and out of overdrive. I have talked to a number of people who have towed in overdrive and some who have locked out overdrive. The common result I have been told is that those who use overdrive in hilly country have all had transmission failures much sooner than those who stay out of overdrive in those conditions.

dstalzer is offline   Reply With Quote
Old 01-06-2010, 02:14 PM   #11
2 Rivet Member
1999 25' Safari
Fairburn , Georgia
Join Date: Jul 2006
Posts: 74
AMEN, Dennis
JackMac is offline   Reply With Quote
Old 01-06-2010, 02:23 PM   #12
Rivet Master
Airstream Dealer
Inland RV Center, In's Avatar
Corona , California
Join Date: Feb 2002
Posts: 16,499
Images: 1
Towing in overdrive, puts a heavier load on the engine, and raises the cylinder head temperature, that could lead to engine problems.

Also, if a vacuum gauge was hooked up the the intake manifold, or vacuum system of the engine, that when towing in overdrive, the vacuum gauge reading will show a lower reading, confirming a heavier load on the engine.

The heavier the load, the lower the vascuum, the higher the manifold temperature.

Towing a small Airstream, probably no problem. Towing a larger Airstream, total different story.

Inland RV Center, In is offline   Reply With Quote
Old 01-06-2010, 02:43 PM   #13
4 Rivet Member
azfiredog300's Avatar
1971 25' Tradewind
Surprise , Arizona
Join Date: Dec 2007
Posts: 346
Andy, I always tow in "Tow/haul" mode until I get to highway speeds then I would turn it off to be in overdrive. So that I understand this right, you are saying that I should stay in "Tow/haul"? I tow with a 2001 Yukon XL. I am glad this question came up because I thought I might be doing it wrong.
Jerry C.

"Travelstar Galactica"

WBCCI #13317
AIR #25664
Member of the Four Corners Unit

The only true failure is the failure to try.
azfiredog300 is offline   Reply With Quote
Old 01-06-2010, 02:58 PM   #14
Vintage Kin
slowmover's Avatar
Fort Worth , Texas
Join Date: Nov 2006
Posts: 7,784
Images: 1
Vacuum gauge is invaluable.

1990 35' Silver Streak Sterling; 9k GVWR.
2004 DODGE Cummins 305/555; 6-manual; 9k GVWR.
Hensley Arrow. 12-cpm solo, 19-cpm towing (fuel)
Sold: Silver Streak Model 3411
slowmover is offline   Reply With Quote

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Airstream Isuzu Diesel THM475 + Overdrive 44tonner Classic Motorhomes 21 09-19-2009 12:03 PM
FAST automatic overdrive transmission controller wmarsha Tow Vehicles 0 09-01-2009 09:38 PM
GEAR VENDORS overdrive, same as units IPM Mechanics Corner - Engines, Transmission & More... 12 07-02-2004 09:13 PM
Overdrive (ie; US Gear) VS trans upgrade ... Hayseed Mechanics Corner - Engines, Transmission & More... 24 07-17-2003 08:19 AM
Opinions on Gear Vendors under/overdrive rdm Mechanics Corner - Engines, Transmission & More... 0 10-15-2002 10:36 AM

Featured Campgrounds

Reviews provided by

Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 05:58 PM.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.

Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.