whatcha got?

[batts496]

Seeing that there are so many of the gasser guys posting on this board,lol, my question is; What do you drive and what and how much do you tow with your 6.0 and 8.1's? I pull a 33' silver star supreme horse trailer, truck and trailer total weight is around 18,000 lbs, give or take, got around 3000lbs on the pin. milage empty is in the area of 11.0 mpg, loaded is 8-9.5 depending on the terrain. If I keep the rpm at or below 2000, around 60 mph loaded I can squeeze out about 10 mpg. On the highway, flat ground no A/C, running a steady 55mph for 100 miles I mannaged a whopping 14.3 mpg. I have yet to find an injector blowing diesel into the crankcase! Not complaining about my milage, just stating what I know, I'm all about some bigblock. Every other piece of equipment that I got is diesel, except my old push mower! I believe that this is my second post and I've been registered since august 2001, the day I bought the truck, 37000 miles as of yesterday afternoon.

[Heartbeat Hauler]

Ha! My wife drives an '04 Suburban 2500 LT 6.0L, but the only thing she hauls is my big butt :D Towing chores fall to the '01 3500 Dmax/Allison w/Banks goodies, and we pull a 2001 Forest River Sierra 30ft 5ver. Eh Eh, Mazdas ain't the only ones that can....Zoom Zoom. ;)
JP

[madmatt]

My old 00' 6.0l has done many a mile hooked to either my 28' tri-axle flatbed, 24' Storm enclosed hauler or my previous 37' Storm enclosed hauler w/ living quaters. the worst milage I got pulling any was 10mpg pulling my 37'er back from PA. I got about 17 empty. I don't know what the big'in weighed but it was heavy. All I hauled was 4 race quads, welder, compressor, tools, water, fuel, spare parts and tires and my clothes/gear. I used my flatbed for hauling Dodges and Fords to the shop :D

[markrinker]

My 2003 K3500 6.0L typically pulls a 25' dovetail dual axle trailer, averaging 6K loads, some as high as 12K. My mileage hovers around 9 with trailer, 11 empty.

Today I had the stock backpressure maker replaced with dual Flowmasters wheezing through dual 2.5" pipes dumping out each side between the duals and mudflaps.

It sounds great!

[madmatt]

mine flew through flowmasters as well. No cats dual 3" from the gibson headers back. The pcm was an SLP as was the intake. the filtering was done w/ foam.

[motorhomeguy]

Running an 8.1L in a 38' Class A motorhome. Traveling weight is 24,000 lbs. solo, 29,000 lbs. when towing my full-size Chevy 4x4 pickup behind it. Runs like a raped ape and gets 6-9 mpg depending on terrain.

There's definitely no replacement for displacement... ;)

[markrinker]

Madmatt - I am considering a performance PCM. Wester's has one for $499. How do I get prices on the one you mentioned?

Did you notice significant 'seat-of-the-pants' performance? Mileage better or worse? Rev limiter removed? (Although I have never hit it with mine...)

I plan to pull the truck this summer in a few local truck pulls. Am considering a 100-shot wet nitrous kit.

[madmatt]

check out SLPONLINE web page (http://www.slponline.com) They specialize in GM mods. They have heads, cams, programs, headers, etc,etc...Yeah the reprogrammed PCM was a major boost! I also ran their cold air intake, rocker arms and cam. For SLP's hottest program you're looking at about $450 and you get:

Recalibrate speedometer for non-stock gear ratios*
Remove top-speed limiter*
Disable Computer-Aided Gear Selection (CAGS)**
Disable torque reduction**
Disable shift delays**
Increase shift firmness**
Raise rev limiter**
Raise WOT shift points**
Adjust cooling-fan activation points**
Adjust AC shut-off for WOT**
Disable vehicle anti-theft system**
Disable catalytic-converter over-temp feature**
Disable EGR**
Disable air pump**
Disable specific error codes**
Install SLP High-Performance Spark Advance***

they do all the high performance applications for GM: the WS6, Z06, SS and so forth. If you were to go to a dealer and order a WS6 specific part, we probably turn around and order it from SLP depanding on what it is.

[madmatt]

whit all that I made a hair over 400 ponies @ the RWs and still got 14 mpg after the mods. i never made any long hauls w/ these mods though. before the cam and rockers I got about 16mgh.

[markrinker]

Interesting. Are you running a stock cam? Crane makes three custom grinds for the 6.0L. I want one that makes more HP/torque down low.

[madmatt]

No, I was running a cam from SLP/ It was the same specs as what made it's way into the LS2. I understand Comp makes a good 6.0l grind as well. whichever way you go the stock rockers gotta go and I upgraded to SLP pushtubes as well. I figured it was cheap insurance since I was in there already.

[markrinker]

So is this the correct order of mods?

1) Exhaust (done) +15 hp
2) High flow air Filter +5 hp
3) Cam / Lifters +25 hp
4) PCM +25 hp
5) Heads? ?

What about injectors?

[madmatt]

Lets see...I did the headers and exhaust along w/ the cold air intake first. then I did the PCM, after that I got a little more radical and did the cam, rockers, pushtubes, retainers and keepers and now that you reminded me I installed a set of matched flow 35lb hr injectors and an aftermarket MAF sensor, but I can't remember where I got it.
Beware!!! After all this your tranny will need upgraded. Mine never got hot just cruizn' but when you hooked up or chained down you could tell it was suffering. I unloaded mine about 1 1/2 years ago because I could tell the tranny was going to need worked over and since I was building a house and changing jobs I didn't want to sink any more money(hopping it up anyway) into a truck w/ 90 some thousand showing on the odometer. Wish I'd kept it now! :(

[markrinker]

Thanks for the insite. I think the programmer is next. I could use some MILEAGE - I am getting 8 loaded and 9 unloaded, but I haul a** at all times, too.

I broke a clutch in my 4L80E at about 38K miles. The covered it under warranty, and rebuilt the transmission as well.

At ~45, reverse let go. Again, they repaired the transmission under warranty, but since I use the truck for commercial towing - I am now 'on my own'.

I'll probably pursue the mods anyway and replace it with the new Chevy 4L85E when it craps out. My understanding is that the '85E has some heavy duty parts in places where the '80E commonly fails under high HP applications...

[madmatt]

I ran from Mt Morris PA to Louisville, KY in 6 hours w/ one fuel stop and still got 11mpg pulling my 24'er. there was a three or four truck "mini-convoy" and we were moving to slow if we were go less then 90 mph. that was before the real nasty but after the PCM mods and of course my rig is probably a lot lighter.