Suburban big block
- Thread starter Powderboy
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I don't think they changed power output in the Suburbans due to them being mated to the 4L80E in that chassis ... on the pickups they upped the power output by like 25 horse in 2004 I believe.
I'd try to find the one in the best shape with the fewest miles regardless of the year.
I loved my 2005 2500HD with the 8.1L .... If that truck would have been a crew cab I doubt I'd have a Cummins sitting in my driveway
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Powderboy
Well-known member
I don't think they changed power output in the Suburbans due to them being mated to the 4L80E in that chassis ... on the pickups they upped the power output by like 25 horse in 2004 I believe.
I'd try to find the one in the best shape with the fewest miles regardless of the year.
I loved my 2005 2500HD with the 8.1L .... If that truck would have been a crew cab I doubt I'd have a Cummins sitting in my driveway
Thanks for the feedback. You always hear complaints about fuel mileage. How bad was it really?
I bought an 03 new..great truck... fuel milage wise..if you can handle your right foot(hard to do because the motor gets it) they do pretty good(empty on the highway, 14-16 at 55-60 mph.. if you feel the need for speed..well it will get down into the 8's..loaded with a 4500 pd 4 place open, cruiseing, about 10...hauling butt..about 7...pulling a 10000 pd travel trailer, about 7-9 depending on how hard you push it..now that's here in AK(I drove mine here new from Utah in 03) where everything is up/down and lots of hard pulls, driving it up empty, we averaged about 18 for the trip(about 4000 miles) but the flat areas down south really helped the average out..HP wise the burbs came rated higher on HP then the pickups did (at least in 03) and they are bad *** for pulling a load.........
About 5% overall worse than the current crop of GM 6.0L motors, and its not even funny how much better they tow.
On my 2005 2500HD ECSB with 3.73 gears, and 265 or 285 tires I would get 8-10 mpg towing @ 75 mph depending on wind, 9-11 @ 65 depending on wind, and I would get about 14.5-15 unloaded @ 75 on and 15-16 @ 65 mph .... Conversley, I had exactly the same truck for a work truck but a 2009 with a 6 speed and it maybe averaged 1-1.5 mpg better than my 8.1L did and didn't tug near as well.
I think with the suburban being heavier, you'd actually see slightly worse mileage than I posted however, but its not going to be appreciably worse than the same vehicle with a 6.0L ....
I had an '01 Yukon XL for 4 years and approx 40K miles. I loved the Yukon and the 8.1L, but it struggled some towing my 10K lb travel trailer. I wasn't too concerned about fuel mileage as the Yukon was the "right tool for the job". I did keep track though. I don't believe I ever got over 12mpg. Maybe when just while cruising at 65 or slower, but rarely. I would normally get 11-12 unloaded combination driving. When towing my 7x29 Aluma loaded, I would get 8-8.5 at 75 on interstate. When towing my 10K travel trailer, I would get 6-7mpg. It would struggle pulling up some of the mountain passes. "I think I can, I think I can"...but would always make it and never let me down. I've since replaced it with a '08 suburban that I had converted to a Duramax/Allison. I just got back from Cooke (1950mi round trip) and averaged 12.0mpg (I get 20+ unloaded - EFI live tune). Very happy and it just yawned at the Chief Joseph switchbacks. You will be happy with the suburban. I've got a wife, 3 kids and 2 dogs. It is the only way to go!! If you can, get a 2003-2006...more bells and whistles. I was not happy with the 6.0 in my 2008, but knew I was going to swap it out with diesel. Mark
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Powderboy
Well-known member
Hmm...sounds interesting. I have a 13 Denali HD with dmax and a 96 Powerstroke. I don't really need 2 pickups so I thought maybe I would swap out the Powerstroke and get a big block burb just for the heck of it. I have 5 kids, a hot wife and 2 grand baby's so I figured somehow I could put the extra seats to good use...
Man looks like finding a nice one is going to be a job. There's a few here in Seattle but they are all pretty hammered.
Man looks like finding a nice one is going to be a job. There's a few here in Seattle but they are all pretty hammered.
What is the total cost of having a Duramax/Allison swapped into a Suburban? Do I even want to know?
I know you could sell 6.0L/6L80E and associated hardware easily enough, but that's still gotta be at least a $12,000 deal? And it'd have to be in a state you don't have to pass a smog pipe test, right?
I know you could sell 6.0L/6L80E and associated hardware easily enough, but that's still gotta be at least a $12,000 deal? And it'd have to be in a state you don't have to pass a smog pipe test, right?
I spent about $21K to have mine converted. I bought a totaled donor for $10.5K and added a few goodies (exhaust, EFI Live tune, 17K lb hitch), the rest was labor. The 03-06 are cheaper because the donors are cheaper. The only way to do it cost effectively is buying a donor.
The following is a link to a video of when my burb was just finished. It was shipped back to me a day later.
https://www.youtube.com/watch?v=mrcWt6sZgpQ&feature=c4-overview&list=UUikeLGzl891UgeABbfK_tbA
BTW - you can have all emission equipment from Duramax installed. The older the better as there are less/no emission equip, but Duraburb has done full emission LML conversions (2011-2014).
Mark
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It's no worse than any of the newer 3/4 ton gassers.
I got a F250 6.2L 2013 right now that does 12-13 mpg empty summer commuting. About 10mpg winter majority in 4wd, and 8-9 mpg towing my 2 place enclosed loaded with 3 sleds and 1 in the bed.
The 6 speed trans is nice but it doesn't pull like the old 8.1 Chevy.
They made the 8.1s with the Alli behind them but not sure if that was just the pickups.
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Powderboy
Well-known member
no.
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catrider800
Member
Had an 04' Yukon XL with the 8.1 4.10 gears 285 tires. Got 10-11 empty and averaged about 7-8 on two trips to Montana towing a 7x27 enclosed. Great vehicle for hauling 5 guys a long ways.
That sounds about right.
Whenever someone posts some numbers that are too good to be true, they are false.
exactly , 3.73 trucks maybe got 12 mpg.
6.0L subs got 14 mpg tops with 3.73
If the dealer or Owner don't know the ratio, GT4= 3.73 , GT5 = 4.10 , G80 = posi traction. This info will be listed on the glove box sticker with all the 3 letter codes and the VIN
