Trailering in OD
 

I always keep the overdrive off when trailering around town but is it necessary to keep it off when you are on the interstate maintaning a constant speed? Trying to get better than 8.3MPG on the interstate:cry:

depends on your truck and load.... with my dually I towed at 29,000 lbs gross for thousands of miles in overdrive... I have never had a vehicle that I couldn't tow in overdrive without issue except for a jeep cherokee that would constantly shift up n down so I'd tow in drive w it.

As stated--depends on your tow rig.

I towed boats over 40000 miles in a year with my Tahoe, boats from 20 to 27', and always left in overdrive. The computer will tell the tranny what gear it needs to be in.
PS-That is the factory trans in the Tahoe with 188,000 miles, serviced every 30,000 though.

I was alway told by my Tranny guy never never tow in OD!! So I have always left it in 3.
That said when using a GM in the tow mode it changes the shifting to a higher RPM for better power but will go into OD when up to speed. Ford does the same but did not go into OD, thats what I was told on a few year old trucks have no idea in the new? My chevy will go in OD at speed up to my year 2009. either way the best thing if your truck has a temp gauge for the tranny (most newer stuff does) do not tow if the temp is any higher then the engine!

Look at the computer and see what the mpg is when in OD and not.
In my situation I found I get the same or better mpg by turning the OD off.

Yea 3mpg difference....doesnt sound like alot but thats a 30% increase for me.

MJ - I was ALWAYS told the same.....thats why I had to ask

I have a 2005 Chevy 2500HD and the boat with my gear comes in right under 4000#(truck excluded)........I also hate that when OD is on with cruise control and I hit an overpass, the SOB acts like it wants to redline to get up it and just guzzles gas.....

I will try w/o the OD on this next trip and see how it goes. At 1200mi roundtrip I need all the help I can get!!! Especially when my normal fuel econ with no load is 11.3mpg!!!! Ol girl is tough but she aint a cheap date by any means......

OD off and slow down to 55 - 60mph.

personally I wouldn't even consider turning the o/d off with that truck and that tiny load (unless you have airplane gears and it is shifting a lot) but if you slow down as mentioned above you will save LOTS of gas.

Read the owner's manual... it will tell you what gear to tow in.

The closest truck I had to that one was an old 94 chevy 2500 4x4 ex cab with 4:10 gears... It had no trouble towing a 10,000 lb 38' fifth wheel AND a jeep wrangler on a towbar behind the camper in O/D and I HAVE to believe that your truck is WAY tougher than that old pig was.... the best thing you can do for your trans tho is to add an aftermarket trans cooler.... I put them in all of my towpigs...

I will say that my trans in my dually DID finally give out while pulling at 29k lbs but she had 330,000 HARD miles on her at the time so I can't fault it.

With my 29k dually camper and jeep combo mentioned above I can get 10+ mpg at 55 and with cruise on 78 I get 6.6 mpg

Put it in tow/haul mode and go with it. No need to shut OD off for that. Heck I've towed ALOT more than that with a 6.0L 3500 SRW, and it towed just fine and stayed in OD. As for revving up, the VORTEC engines do NOT like to be lugged down. They run the best high up in the RPM's, and it is probably helping your mileage in doing so(and also helps your trans).