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BrianM
11-14-2005, 06:22 PM
Just wondering what those of you with GM trucks and SUVs with the 5.3 are getting for gas mileage while towing. Just got back from my first long distance tow of approximately 1200 miles round trip and would have to say I am a little disappointed.

I have an '03 GMC Ext Cab Shortbed 2wd with the 5.3 and 3.55 gears. It has 70k miles on it. Generally in combined driving of about 60% highway 40% in town I get a very consistent 18mpg which I think is pretty darn good for a full sized truck. I used to do some short tows of about 40 miles round trip but it was always mixed in with normal driving. I saw the mileage drop but not all that much when say two round trips of 80 miles was factored in over a tank of gas.

Over this past trip all just towing my 190's which would mean a load of just over 3200 lbs boat and trailer I averaged right at 13 mpg over the trip :( . Best tank was 13.1mpg and worst was 12.8mpg. Now this was a pretty flat trip but spead was pretty much 75mph the whole way. Is this what others are experiencing?

Everything I hear here and elswhere is that the Hemi Dodges suck the gas. 13 mpg makes me ill so if the Hemi gets that mileage in general and worse towing I am sure glad I don't own a Dodge ;)

Ric
11-14-2005, 06:29 PM
sounds normal to me
Do you have OEM tire diameter?
I don't, so my mileage is innacurate when calculated per my odometer. Mine is a 6.0, 4x4 crew with 3.73 gears and I get around 12ish at best towing fast like you.

Just wondering what those of you with GM trucks and SUVs with the 5.3 are getting for gas mileage while towing. Just got back from my first long distance tow of approximately 1200 miles round trip and would have to say I am a little disappointed.

I have an '03 GMC Ext Cab Shortbed 2wd with the 5.3 and 3.55 gears. It has 70k miles on it. Generally in combined driving of about 60% highway 40% in town I get a very consistent 18mpg which I think is pretty darn good for a full sized truck. I used to do some short tows of about 40 miles round trip but it was always mixed in with normal driving. I saw the mileage drop but not all that much when say two round trips of 80 miles was factored in over a tank of gas.

Over this past trip all just towing my 190's which would mean a load of just over 3200 lbs boat and trailer I averaged right at 13 mpg over the trip :( . Best tank was 13.1mpg and worst was 12.8mpg. Now this was a pretty flat trip but spead was pretty much 75mph the whole way. Is this what others are experiencing?

Everything I hear here and elswhere is that the Hemi Dodges suck the gas. 13 mpg makes me ill so if the Hemi gets that mileage in general and worse towing I am sure glad I don't own a Dodge ;)

BrianM
11-14-2005, 06:30 PM
sounds normal to me
Do you have OEM tire diameter?

Yep, OEM size 255/70/16

ted shred
11-14-2005, 06:38 PM
That doesn't seem to bad considering your speed. Was this in overdrive? I have found sometimes it's best to go slower with the tranny in drive as it keeps the rpms in the most desirable range for good torque from the motor.

rodltg2
11-14-2005, 06:43 PM
just did a long tow of about 400mi. i averaged 10.9 after installing a cool air intake. im happy. i was getting about 9.5.

JDK
11-14-2005, 07:02 PM
Everything I hear here and elswhere is that the Hemi Dodges suck the gas. 13 mpg makes me ill so if the Hemi gets that mileage in general and worse towing I am sure glad I don't own a Dodge ;)

I think you're right, but, unloaded.
From what I've seen with buddies trucks, loaded, they are pretty good. The problem is, how often is a guy towing 4000+ lbs.

Andyg
11-14-2005, 07:08 PM
That beats my F150 with the 5.4L Triton. I get about 10 mpg whenever I tow my 197 on the interstate.

BrianM
11-14-2005, 07:14 PM
That doesn't seem to bad considering your speed. Was this in overdrive? I have found sometimes it's best to go slower with the tranny in drive .

I tow in drive with the transmission in Tow Haul mode. RPM at 75mph was about 2150. I am sure that driving 60 mph probably would improve mileage substantialy but I am not willing to sacrifice hours of my life for a little better mileage. 1200/75 = 16 1200/60 = 20.

That beats my F150 with the 5.4L Triton. I get about 10 mpg whenever I tow my 197 on the interstate.

Guess I am doing pretty good considering the circumstances (higher speed). Was just checking to see if this was normal. I'll consider myself lucky and just go back to telling myself that I have to pay to play.

Workin' 4 Toys
11-14-2005, 07:16 PM
My '04 Yukon gets about 15mpg. Haven't towed with it yet since I have the P'stroke. But I may take it 1000 miles with the sleds on it in a few weeks. If I rememeber Ill post my results.

dog paw
11-14-2005, 07:21 PM
Yes thats pretty good. A friend of mine has the 6.0 Chevy that he pulls a Ranger bass boat with. I think he is lucky when he gets 10 mpg. I rarely pull with my Yukon and never in overdrive, I think it runs around 13mpg towing. My Powerstroke gets 17 with or without the boat.

Andyg
11-14-2005, 07:23 PM
I rarely pull with my Yukon and never in overdrive, I think it runs around 13mpg towing.

I also never tow with the truck in overdrive. I would rather pay a little more in gas than have to rebuild a transmission after 50,000 miles. I used to tow about 3000 miles a summer, now that will hopefully change that I have a cabin to keep the boat at. One of the selling points to the wife was the gas savings.

Nuts4Water
11-14-2005, 07:27 PM
I towed my boat to Shasta last Summer from Portland OR with my Suburban and got about 9.5 miles per gallon during the trip. Unloaded it gets about 12-13 average.

BrianM
11-14-2005, 07:31 PM
I also never tow with the truck in overdrive. I would rather pay a little more in gas than have to rebuild a transmission after 50,000 miles. I used to tow about 3000 miles a summer, now that will hopefully change that I have a cabin to keep the boat at. One of the selling points to the wife was the gas savings.

I used to sell GMC trucks and in reading the manual for the 5.3 trucks and talking to the Service Tecs it is reccomend that when towing to leave the vehicle in D drive and use the Tow Haul mode. This changes the 'program' of the transmission specificly for towing increasing the amount of rpms that the transmission will hold in each gear before upshifting and causing the transmission to kick down to a lower gear sooner to avoid lugging. 'Overdrive' is just 4th gear and there is no detriment to towing on the flat interstate in 4th gear.

Upper Michigan Prostar190
11-14-2005, 07:39 PM
When I towed my MC home this spring, I used my parents Tahoe with the 5.3L and standard OEM tires. We used the "Tow/Haul" mode on the transmission and the trip was approx 1000 miles. We had my prostar 190 on the trailer, 3 guys all 190-235 lbs range, some luggage and tools. depending on who was driving, we got around 14 to 15 MPG towing. But when My buddy was driving and he hit michigan, he wound up to 80 MPH and that destroyed the fuel economy to about 10 MPG. :eek: thats my expereince with it. thats the only long distance towing I did with it.

OH yea, and Word UP on what BrianM said about TOW HAUL mode. It RULES!!!! I work at a GM shop too and thats what our techs advise as well. works like a charm :twocents: JR, can you hit me up with a "Tru dat" here :cool:

UMP

Ric
11-15-2005, 12:25 AM
I tow in tow haul mode but I wish I had the patience to kick back 'round 60 while towing and just see what my mileage would be... Nah, gotta get to the lake!

When I towed my MC home this spring, I used my parents Tahoe with the 5.3L and standard OEM tires. We used the "Tow/Haul" mode on the transmission and the trip was approx 1000 miles. We had my prostar 190 on the trailer, 3 guys all 190-235 lbs range, some luggage and tools. depending on who was driving, we got around 14 to 15 MPG towing. But when My buddy was driving and he hit michigan, he wound up to 80 MPH and that destroyed the fuel economy to about 10 MPG. :eek: thats my expereince with it. thats the only long distance towing I did with it.

OH yea, and Word UP on what BrianM said about TOW HAUL mode. It RULES!!!! I work at a GM shop too and thats what our techs advise as well. works like a charm :twocents: JR, can you hit me up with a "Tru dat" here :cool:

UMP

whitedog
11-15-2005, 12:38 AM
2500 HD 4x4 6.0 tow ot haul about 50 % of time has 4:10 gears and 265 75 16 tires. Towing under 6000# average 12-13 over 6000 up to 14000 average 10. No load 17-18. Towing under 4000 overdrive tow/haul mode over 4000 driver and tow/ haul mode. Towing over 60 mph seems to drop milage about 1 mpg.

My 98 K1500 4x4 with 5.7 and 3:83 gears gets11 mpg towing the boat 70 mi round trips several time a a week. and 17 mpg empty.

Still better than the pathefinder I had got 14 mpg all the time with a 5 speed to boot.:(

dog paw
11-15-2005, 08:45 AM
2500 HD 4x4 6.0 tow ot haul about 50 % of time has 4:10 gears and 265 75 16 tires. Towing under 6000# average 12-13 over 6000 up to 14000 average 10. No load 17-18. Towing under 4000 overdrive tow/haul mode over 4000 driver and tow/ haul mode. Towing over 60 mph seems to drop milage about 1 mpg.

.:(

The HD has the sweet trans, 4L80. IMO thats just under the Allison It's a tough one. The rest of us hehe have the lil 4L60 It uses the band over 3/4 clutch unit to get OD. NOT a good setup to pull loads with. The tow haul mode is a big help if you have it

OhioProstar
11-15-2005, 09:17 AM
I have an '03 with the 5.3liter, 3.73 rear, and 285/75/16 BFGs. It gets around 16 day to day and 13 towing the boat, a lot of gear/beer, and a couple people. The manual actually says not to use tow/haul with a trailer that weighes less than 4000lbs.

Ric
11-15-2005, 09:34 AM
I have an '03 with the 5.3liter, 3.73 rear, and 285/75/16 BFGs. It gets around 16 day to day and 13 towing the boat, a lot of gear/beer, and a couple people. The manual actually says not to use tow/haul with a trailer that weighes less than 4000lbs.
sounds really good, have you recal'd the speedo for the 285 tires?

OhioProstar
11-15-2005, 09:38 AM
Not yet...I am thinking about dropping a Westers chip in..but with the new GMT900 line coming out I might just wait. The Speedo is off about 3%.

east tx skier
11-15-2005, 10:05 AM
I tow in drive with the transmission in Tow Haul mode. RPM at 75mph was about 2150. I am sure that driving 60 mph probably would improve mileage substantialy but I am not willing to sacrifice hours of my life for a little better mileage. 1200/75 = 16 1200/60 = 20.



Guess I am doing pretty good considering the circumstances (higher speed). Was just checking to see if this was normal. I'll consider myself lucky and just go back to telling myself that I have to pay to play.

I think you've got it. You'll do better mileage-wise at about 60 mph. But even though I have more time than money, I usually tow at 65--70 mph. My Ford manual suggests that I could get better mileage towing with overdrive turned off. Haven't tested it as I always have it out of overdrive when towing. My typical out of town tow is just over 100 miles and I will burn approximately 6.5 gallons of gas in the process. So that puts me in the 15 mpg range. Remember, this is approximate, so I'd bet it's a little lower. (01 Exped. 5.4 Triton, 3.33 rear axle).

I always complain about that weak rear axle ratio except when I'm on the highway.

LakePirate
11-15-2005, 10:17 AM
I have the 5.4 in my Avalanche and get around 13 or so when towing, it is much worse in the wife's tahoe. Don't really know why.

I don't buy that drive 60 crap, the point of diminishing returns has to be much higher. Explain when I am driving a car with one of those fancy computers that gives me the current avg mph why when I start rocking it at 85 or so the economy picks up?

east tx skier
11-15-2005, 10:20 AM
I have the 5.4 in my Avalanche and get around 13 or so when towing, it is much worse in the wife's tahoe. Don't really know why.

I don't buy that drive 60 crap, the point of diminishing returns has to be much higher. Explain when I am driving a car with one of those fancy computers that gives me the current avg mph why when I start rocking it at 85 or so the economy picks up?

I ran 85 to Houston this weekend in a freshly tuned Honda Accord with a new air filter and my mileage suffered for the speed by about 3 mpg from my previous trip when I ran 70.

The fuel economy ratings are done driving 59 with the A/C off on a flat surface on a calm day in a vacuum. ;)

I drive 65 when towing because I have a single axle trailer and like my chances of avoiding an accident or weathering a blowout better at that speed. I also drive in the right lane and pass in the left.

The reason my boat isn't a big pile of warped fiberglass at the moment is because I drive a little slower. Funny how missing a moron who crossed the road without looking my direction by an few inches will cause me to slow down a little. Much better being a few minutes late to the lake than dealing with insurance companies, lawyers, and next of kin.

Just sayin'.

Ric
11-15-2005, 10:24 AM
Not yet...I am thinking about dropping a Westers chip in..but with the new GMT900 line coming out I might just wait. The Speedo is off about 3%.
Think twice about the westers chip (tune)
I've done it and while it's definitely peppier and such, the bang for the buck isnt there imo.
They retuned my truck 7 times (killing it completely after the 7th when I told them to put it back to stock and step away from the truck) Had to tow the vehicle to the dealer and get ecm replaced.
Never once did they get the tune right.
I think if you were in canada & could drive up to westers, you'd get a fine tune, but these kids("reps") with laptops (who mean well) can ruin your day, lemme tell ya!

edit Oh and if your speedo is off, so is your mileage if you're using the odometer for miles traveled. It should come out better when you recal actually.

Ric
11-15-2005, 10:26 AM
I ran 85 to Houston this weekend in a freshly tuned Honda Accord with a new air filter and my mileage suffered for the speed by about 3 mpg from my previous trip when I ran 70.

The fuel economy ratings are done driving 59 with the A/C off on a flat surface on a calm day in a vacuum. ;)

I drive 65 when towing because I have a single axle trailer and like my chances of avoiding an accident or weathering a blowout better at that speed. I also drive in the right lane and pass in the left.

The reason my boat isn't a big pile of warped fiberglass at the moment is because I drive a little slower. Funny how missing a moron who crossed the road without looking my direction by an few inches will cause me to slow down a little. Much better being a few minutes late to the lake than dealing with insurance companies, lawyers, and next of kin.

Just sayin'.
and you had the transom straps

east tx skier
11-15-2005, 10:31 AM
Ya know, I don't remember if I was towing with the strap when that idiot pulled out in front of me. I had just had my trailer brake system completely redone (thank goodness).

I was towing with the Grand Wagoneer at that time, which had a curb weight of approx 6,200 lbs and no ABS. Brakes locked immediately (as designed) and I watched the boat and trailer begin to swing out to the right. At that point, I just let off the brake and decided that she deserved it more than the people behind her waiting to cross the highway (that's where the boat was heading. So I laid on the horn and made up some new words for her. Hope she was wearing her Depends.

I don't wish that feeling on anyone. Probably the closest I've come to having an accident and not actually having one. I was, as usual, going 10 mph below the speed limit at the time. It was a good reminder as to why I do that.

Oh, and by the way, that Jeep GW got 10/12 with a tailwind. I was probably getting 6 mph towing that trailer. If I could've gotten 15 mpg highway with that truck, I'd still have it. It was 5.9L with something like a 2.75 or so rear end and a 2 barrel motorcraft carb. You could watch the gas guage fall. I never let it get below 1/4 tank (except once).

OhioProstar
11-15-2005, 11:06 AM
[QUOTE=LakePirate]I have the 5.4 in my Avalanche and get around 13 or so when towing, it is much worse in the wife's tahoe. Don't really know why.QUOTE]

I think you have a 5.3 under the hood....My buddies Tahoe gets around 18 miles per gallon. I think it has to do with a closed chassis vs. the tailgate on a truck. I think they might be geared up a bit too.

Evan Jones
11-15-2005, 11:24 AM
Just about all 2006 GM V-8s are coming with the displacement-on-demand technology that shuts down half the cylinders. This usually adds 3-4 mpg.

Evan Jones
11-15-2005, 11:26 AM
[QUOTE=LakePirate]I have the 5.4 in my Avalanche and get around 13 or so when towing, it is much worse in the wife's tahoe. Don't really know why.QUOTE]

I think you have a 5.3 under the hood....My buddies Tahoe gets around 18 miles per gallon. I think it has to do with a closed chassis vs. the tailgate on a truck. I think they might be geared up a bit too.

My 5.3 Tahoe (Z-71) has the 4.10 gear option which brings mileage down to 15-16.

milkmania
11-15-2005, 12:49 PM
to sum up gas mileage........

I've got 3 suburbans & a full size blazer in the driveway,
'93-3/4 ton 4x4
'95 1/2 ton 4x4
'97 1/2 ton 4x4
&
'88 K5 Blazer, yes, the K means it's also 4x4
(never had payments on any of them)

I did not buy a single one of them for gas mileage, I bought them for comfort & room, and I couldn't be happier!

now, in my situation, I do not drive them to work daily, if I did, I would drive a more economical newer vehicle.....then I would have fuel & payments to contend with.

I've worked vehicle accidents where smaller cars have collided with larger vehicles, and it's not good.
I've also seen accidents where suburbans have hit other full size trucks, again, it's not good.....but the chances of my children surviving a head on collision are greater as they're always in the middle row and buckled!

Rockman
11-15-2005, 02:48 PM
We have a 2002 HD2500 extended cab 6.0 Gas with the 4:10 gear.

I drive the truck to work everyday which can be stop and go for most of the way. So needless to say, my gas mileage $uck$.

When we head up north, I usually get good gas mileage since it's all highway driving usually about 70 to 75mph. But I can honestly say that when the truck is loaded and / or we are towing our MC or both, I get better gas mileage. Go figure. I think it's the way our truck is set up. We still have the OEM tires on it so maybe that is something to consider.

I will check this weekend to actually see what our MPG is. It's probably about the 13 range as most of you have noted.

Any changes made to the muffler, air filter, etc that would be recommended to get the truck to run more effiiciently?

I always tow in D since we have no overdrive and rarely use the Tow Haul Mode unless we are at a steep incline or ???

Do you guys actually tow with the Tow Haul Mode on all the time? I didn't think that was good for the trans, etc. :confused:

Kinda funny though, my wife says "the truck drives like a dump truck when it is empty" and I say "ya, it drives like cement truck when it's full." :D

6ballsisall
11-18-2005, 09:35 PM
JR, can you hit me up with a "Tru dat" here :cool:

UMP


Catching up on my reading here......

Tru Dat :cool:

Workin' 4 Toys
11-19-2005, 12:14 AM
I've worked vehicle accidents where smaller cars have collided with larger vehicles, and it's not good.
I've also seen accidents where suburbans have hit other full size trucks, again, it's not good.....but the chances of my children surviving a head on collision are greater as they're always in the middle row and buckled!
Obviously I agree here, having two behemoths myself. But, these rigs do not hold their own well against even larger rigs, and or the inevitable rollover. I have seen quite a few. The ride height vs. safety is somewhat misleading to the drivers who do not respect the center of gravity. Not to mention the T-bone.

h2oskier
11-19-2005, 12:27 AM
I am getting a solid 13.1 mpg. I also tow a '03 209 with it and don't see much change in mpg. I am wondering what I can do to improve my milage. I am going to add a bed cover, but what else can I do. Any suggestion would be helpful.

Jim
11-20-2005, 11:14 PM
03,4WD, 5.3 Ltr Burb. 3.73's towing 04 X10/ tandem trailer 4500 Lb. / 11.7 MPG at 70 MPH

6balls
11-20-2005, 11:25 PM
:) I am running my 2005 Suburban on E-85 (http://www.e85fuel.com/index.php) (85% Ethanol - 105 Octane) as it is a Flexible Fuel Vehicle. Runs great and is under $2/gal now.

captain planet
11-21-2005, 05:27 PM
[QUOTE=BrianM]

Over this past trip all just towing my 190's which would mean a load of just over 3200 lbs boat and trailer I averaged right at 13 mpg over the trip :( . Best tank was 13.1mpg and worst was 12.8mpg. Now this was a pretty flat trip but spead was pretty much 75mph the whole way. Is this what others are experiencing?

QUOTE]

Brian, speed kills. I can't speak for my 5.3 while towing because I haven't towed for long distances with it, but in a recent trip to Georgia and back I noticed a huge difference with regard to speed. With 6 people on the way to Georgia (not towing either way) going about 70 miles per hour I was getting 17.8 to 18 miles per gallon. On the way back, with 7 people, I was pushing it 75-80+ mph, and my mileage dropped to 17 to 16.5 mpg.

My buddy went to Tennessee to get his boat and on the way back (99 Surburban 5.3L) I think he told me he got 14-15 mpg. I'll have to double check with him, but I think that is about right

Thrall
11-21-2005, 06:20 PM
BrianM,
That don't sound too bad for 75 mph down the road w/ your 190 in tow. He!!, I only get 13-13.5 empty in the wifes 01 Dodge 1500, 5.9 gas motor, 4wd. W/ the boat at 75-80mph, get 8 or 9.
My Company rig, 5.4 Ford 2wd gas gets about 12mpg w/ the boat behind it.
Of course, I'm not too easy on the go pedal, but the ole Dodge has never seen more than 14mpg w/ a tail wind downhill.