Towing with 6.0L gas / 4L80E combo?

[Mark Rinker]

I traded an '03 K3500 6.0L gas / 4L80E dually last spring in favor of an '02 Duramax. While I believe the decision overall was a good one, the lack of aftermarket tunes/products to 'correct what ailed' the gasser also played a part in the trade decision.

My truck got 8-9mpg loaded, and the tow/haul shift programming was HORRIBLE. Constantly 'hunting' from OD to D, downshift and over-revving, etc.
The poor shift characteristics of the stock OEM program and overrevving when towing was a big factor for me in low satisfaction and eventually trading the truck.

Q: Is anyone towing heavy and regularly with this combo? What are your reactions to mileage, shift quality, etc.? Running any Hypertech or similar tunes? Which are the best?

Idea: Switchable tune for regular unleaded / E-85, with improved shift points for Tow/Haul setting, either fuel. Whaddya think?

[ECMProgrammer]

I know you're the head agitator here (and nobody can tune anything except EFI-Live even though they've only been out for a year) send me your VIN and I'll make up a nice FREE tune for your truck. I won't promise you mileage gains--but HP and shift correction won't be a problem. Did I mention it was FREE...
I've been tuning these rigs since they were released--you can check our feedback on gasser rigs on any reputable forum that's been around longer than a couple years.


Lyndon
www.ecmprogrammer.com
Westers Garage
1-888-WESTER-1

[Mark Rinker]

Thanks for the offer, but I sold the 6.0L gasser truck.

Obviously the tuner software market has become incredibily competetive. I wrote and supported Fortune 500 software systems from '85-'00, and experienced firsthand the incredibily quick lifecycle of proprietary (i.e. profitable) products and their inevitable replacement by commodified (its free!) me too products.

Frustrating, ain't it?

As one astute Product Manager once put it "...there is simply no barrier to entry into these markets. The only answer is to purse the difficult problems for our customers, and get good products to market first, with exceptional customer support."

Wester's was first on the landscape (Apple), but EFI-Live is capturing the intererest of the masses (Microsoft) to 'roll their own' solutions, rather than buy a packaged one. Interestingly, neither is a US based company. Not sure what that means, if anything.

In a few years, I wonder if one or both of the following will be commonplace:

1) Most performance enthusiasts will have an 'electronic workbench' of open software tools in their garages capable of allowing them to easily modify engine parameters realtime to 'fine tune' their vehicles to their particular needs (power/mileage/towing/racing);

2) ECMs will employ 'adaptive learn' logic better adapt any vehicle to its surroundings and use patterns (my owner lives in Denver and tows regularly).

There will always be a place for 'tuners' on the ragged edge of technology and performance! The next few years will sort out the men from the boys.

[DieselMonk]

had a 6.0l in my Yukon XL 2500 with a 4L80E. I've got 11mpg towing a 26ft camper trailer and 13mpg at best highway. Have cold air intake, 160 degrees thermostat, corvette valve springs, a new hotter camshaft, power programmer, headers, cat back exhaust. She has good power over 3000rpm, but the gas milage sucks big time. Even before all the mods to the enginge, I had worse towing at 9 mpg but better on the highway at 14mpg. Lately my avergage is 11MPG. Ordered myself a new 07 GMC Sierra 2500HD with a LMM.

[Mark Rinker]

I think you'll be much happier with the diesel...thats alot of mods for margin returns on the gasser...my experience with 6.0L exhaust, intake and programming mods was similar.

[opardinas]

Like Mark, I too am disappointed with my 6.0-4L80-4x4-4.10 setup. To make matters worse, I really like the way it looks with 285s. I tow about 9K in Southern Cal so I come up against a few steep grades. For the most part I can do OK but the grades really kill me. I get 13+ all around and 7-8 when towing. I have the Hypertech tuner and K&N FIPK.
Unlike Mark, I have opted to stick it out with my 6.0. The rationale is as follows:

1-It is an 04 and I have just 10K miles. I only use it when I go out with my TV or for weekend outings
2-It's really convenient to find gas at every corner
3-There'sa 20K delta to upgrade to a diesel

With that said, what can I do? My next step is to go to 4.56. The rig will cruise just fine in OD to about 61-62 MPH in the low 2000 RPM with TV. Any grade will kick it out of OD. I realize this may be a shift point issue but I can not adjust with Hypertech to hold in gear. I've heard of the Wester's but I have to question how much better that is than what I have now.

Your input is appreciated.

OP

[DieselMonk]

Like Mark, I too am disappointed with my 6.0-4L80-4x4-4.10 setup. To make matters worse, I really like the way it looks with 285s. I tow about 9K in Southern Cal so I come up against a few steep grades. For the most part I can do OK but the grades really kill me. I get 13+ all around and 7-8 when towing. I have the Hypertech tuner and K&N FIPK.
Unlike Mark, I have opted to stick it out with my 6.0. The rationale is as follows:

1-It is an 04 and I have just 10K miles. I only use it when I go out with my TV or for weekend outings
2-It's really convenient to find gas at every corner
3-There'sa 20K delta to upgrade to a diesel

With that said, what can I do? My next step is to go to 4.56. The rig will cruise just fine in OD to about 61-62 MPH in the low 2000 RPM with TV. Any grade will kick it out of OD. I realize this may be a shift point issue but I can not adjust with Hypertech to hold in gear. I've heard of the Wester's but I have to question how much better that is than what I have now.

Your input is appreciated.

OP

Look at the mods I have done to my 2500 YukonXL and I am not happy yet with the performance setup I have. In your case I would try a super charger. Yes, it cost money, but all the little mods i've done to mine cost me the same thing and have less power. A good super charger with intercooler setup should give ya about 50% more power. For the 4L80e are lower /or higher first and second aftermarket planetary gear, that give you more more / less launch. I am done playing with my truck and ordered myself a new diesel with a LMM.

DM

[DmaxMaverick]

When you install a supercharger to a gasser, the only advantage left is the convience of pumping gas. The cost of the charger and install offsets the Duramax/Allison premium, then you're stuck with 1/2 the mileage, and still less power. Gasoline economy will track your power increase. The ratio is still 15:1 with gas, so more air is more fuel, and add to that the parisitic loss to the charger. It's a losing battle. They do run good, though.

[K. D.]

True, but I still remember the hair raising sound of a full house 350 turning 6000 rpms barking through dual 3 inch straight pipes.. (sigh)

K.D.

[Mark Rinker]

I briefly owned a lowered 2000 Silverado C1500 extended cab last summer with a Whipple supercharged 5.3L. It was stinky fast, but I don't think it would have pulled itself out of its own tracks with a trailer behind it.

Since you tow on weekends and don't rack up many miles, I'd stick with the gasser and enjoy. Maybe the Westers tuner guy will help you out with the right tune, and ADJUST THOSE SCREWED UP OEM SHIFT POINTS!!!

[IUPAC]

I just completed an 1800 mi. round trip from Ohio to Maine/New Hampshire across Pennsylvania with my '03 6.0L/4l80e crew cab this weekend. With an empty 4000# gooseneck 10 mpg, on the return trip 10,000# @ 8.1 mpg. The truck performed flawlessly, very comfortable, smooth ride (considering the conditions), the truck could pass anything but a gas station. That is the only thing I'd change. I couple of climbs were difficult, but I kept it at a decent speed without having to rev over 3400 rpm. The toughest part of the trip was west through N.H. on a two lane highway (the only section where my tranny temp went over 160 deg.) D-max would be nice but not for the money, and the frequency of my trailering trips.

[Mark Rinker]

Not bad mileage numbers at all. You said it - for infrequent towing you saved a bundle on your initial cost of ownership, as well as your cost per mile now that gas and diesel have permanently 'flip-flopped' in price.

[Got Diesel?]

I have lots of good work experience with the 6.0 gas version.

We run 3 crew cab shortbed at work. One 02' and two 03'. We tow 28 ft enclosed car trailers in the city all summer long with about 2 ton in each trailer. In the winter all they do is plow snow and pull skid loaders around.

My old truck is one of the 03' and it has had the most pampered life if the three as up to the last year I used it as my personal truck and just drove to job sites with minimal towing. Today it has about 165,000 miles on it (I averaged about 60,000 miles per year for the first couple of years).

The other two are crew trucks and pretty much get the crap handed to them on a daily basis by the guys. They both have 70,000 hard miles on them.

The 02' has been the best truck of the two crew trucks as it has had the minimal repair work done to it. I checked the other day and the 03' was purchased with a extended warrantty and has been in the dealer 17 times for lots of check engine lights, a fuse box that tryed to start on fire after a blower motor failed and has had the exhaust manifolds replace 4 times after the cracked, and has had the rearend replaced after having a axle seal leak in the process finding metal "chunks" in the fluid.

I will get to the point now.

We average about 6-7 MPG with them when in tow.

And I averaged 12 mpg when I handed my truck down to the crews (I peeked at it this summer and the average in the message center said 6.5 mpg)

I have steped up to a 06' Dmax with the allison and am averaging 16 mph with it after 65,000 miles. I get any where from 10-14 in tow with it. I will take the "shine" off it and then it will get handed down the line somewhere in the 150,000 mile range.

The guys are tickeled to get my trucks cause the come loaded with the LT trim. If we order a crew truck it ends up being a silverado model.

[Quack_Addict]

Let me start this post by stating that I am now the proud owner of an bone stock LBZ / Allison -equipped 2500HD crew cab with 8' bed.

Now that we've got that out of the way, my last truck was a bone stock 6.0L / 4L80E -equipped 2500HD crew cab with 8' bed.

The largest trailer I pull on a regular basis is my 23' Rinker on a tandem axle trailer. It's not a particularly heavy boat itself but load it up with salmon fishing gear, 3-4 guys in the truck and all our gear in the bed and you have a pretty typical outing. A normal pull for me is about 200 miles one-way with the last 50 miles on the way there being over some varied terrain. I have never really weighed the full load but I'd say the truck is probably pulling an added 6-7k pounds distributed weight down the road. The 6.0L/4L80E got the job done but in the hills, it was scarry. I will spare you the full story about why I decided to upgrade to the diesel but will go so far as to say it nearly involved a head-on collision while towing the boat because the LQ4 6.0L did not have the cajones when I needed them while I was committed to passing a semi on a 2-lane highway. To my defense, when I pulled out the oncoming traffic was damn near out of sight and an honest 1.5 to 2 miles distant. The 6.0L/4L80E had to go. At that point, I was sold on either the 8.1L or the Duramax.

Anyone who "has to have" a blower may want to consider this package.

http://www.w2wpowertrain.com/pc-122-63-gm-full-size-truck-high-output-intercooled-supercharger-systems.aspx

This is not intended as a shameless plug for their product; I have no vested interest in whether or not you buy a Whipple, Procharger, Vortech or other instead of the W2W kit. All I can say is I know the W2W system is well built and A LOT of dyno time and tuning went into what they have out.

Temper any thoughts of adding power to your truck with a supercharger with the knowledge that the power you add will decrease the longevity of other driveline components. I had the opportunity to purchase one of the W2W kits at a deeply-discounted rate. Thoughts of sitting stranded at the side of the road with a blown-up 4L80E or a rod hanging out the side of my engine block crept in. The decision I made is evident in the first line of this post.

I know, very well, how GM validates production packages and the lengths GM engineers there go through to fail-safe regular production content. NO aftermarket supplier comes anywhere close to what GM does be it in hard products OR calibration / flash tunes. The driving factor for any aftermarket supplier to bring their product to market is the all-mightly dollar. The sooner their product is available, the sooner they can sell it.

[IUPAC]

I surely can understand why you upgraded based on a safety standpoint, however I adjusted my driving habits to compensate. I don't think I need to be traveling that fast pulling that much weight. I did pass when it was safe, but many times I just sat back behind slower trucks and just waited. I wouldn't have saved that much time by passing and definitely saved money not buying a new truck.

[Quack_Addict]

The speed limit on the stretch of highway in question is 55mph -- and the state boys DO enforce it -- so speed isn't that much of a consideration to me. Being able to go up a marginal hill while pulling my boat and not having the transmission stuck in 2'nd gear with the engine wound out to 4000 or 4500rpm while still decelerating was a factor. There was not much margin left for pulling with my 6.0L even on a level grade and that genuinely bothered me for a variety of reasons, passing for one but more importantly getting up to speed to merge safely onto the expressway. I am much happier with the Duramax from a power standpoint. It also gets nearly double the fuel economy of the 6.0L when pulling.

The way I look at it, I had 3 distinct opions:

1. Keep the 6.0L truck 'as-is', be dissatisfied with the trailering characteristics and loaded/unloaded fuel economy of the truck the whole time, and drive the powertrain into the dirt before the odometer rolled 100k.

2. Keep the 6.0L truck but 'invest' in a power adder like a supercharger. Trailering characteristics would have been improved from a power standpoint but at the cost of powertrain durability and decreased fuel economy. Unloaded, the best my 6.0L ever showed was about 13.8mpg. I think there was a tail wind that day. It was normally around 11mpg (unloaded) and somewhere around 8mpg pulling. More air into the engine (supercharger) means more fuel. At the time, there were A LOT of used HD trucks up for sale with the 8.1L/Allison. I did not want to buy a used truck that I knew had been worked hard by the previous owner. I don't think many people buy (bought) 8.1 trucks for their resale value.

3. Cut my losses, sell the 6.0L truck and buy a D/A truck. Used D/A trucks were going for about the cost of what a new one would cost me so it was an easy call.

In my honest opinion, the 6.0L is an excellent engine and I see many practical applications for putting them into the HD pickup line, they just aren't the best choice for semi-regular / seasonal pulling duty like my application required.

[mr. monte]

I had a 04, 6.0 gasser. I didn't want to spend the extra $$$$to get the Dmax. That was one of my more foolish moves:( I LOVED the truck, BUT!!! for towing anything over 6000#, or something with alot of wind resistance...IT SUCKED!!! it would pull my open car hauler great. Anything larger had dramatic effects:eek:

so now I just got my 07 Dmax, and in stock form can not believe the difference, you can't get that power from a gasser w/ the fuel economy