# Suburban 2500 6.0l Or 8.1l??



## ssrrchase

Hi all - I need some input&#8230;. I pull a 26rs with a 1500 Suburban now. I have a chance to upgrade (which I'm taking) and my choice is between a 2500 Sub in either the 6.0L or 8.1L engine. So all you 2500 Sub owners and those in the "know" - which one? Is the 8.1L overkill for a 26rs?

Does anyone know MPG towing and not towing for both the 6.0L and the 8.1L. Is there a big difference? I expect 10 City/12 Highway/9 towing on the 8.1L. Is that close?
Any advice and help would be greatly appreciated.

Thanks,
Steve


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## mswalt

There is no overkill when it comes to pulling safely. Go for the 8.1. You'll never regret it.

Had mine now for about 3 years. Love it.

Mark


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## BoaterDan

I'd be _prepared_ for a mpg or two lower than that in the 8.1, but you're probably close.

There was a recent thread about the 6.0L not being as great as it originally sounded. I've actually been thinking since that thread about trying to find an 8.1L to trade my 7.4L for before they became ridiculously hard to find. The tow rating for the 8.1L was up to 12,000 pounds!!

There's no replacement for displacement!


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## MikeN

I have the 8.1 in a Chevy 2500 hd pickup, mileage is not the best, but it pulls my Outback 31kfw with ease. I get around 15mpg not towing (hwy) and around 9mpg towing (hwy). Around town I only get about 10 mpg. I also have the 4.11 rear.


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## BritsOnTour

mswalt said:


> There is no overkill when it comes to pulling safely. Go for the 8.1. You'll never regret it.
> 
> Had mine now for about 3 years. Love it.
> 
> Mark


Ditto - well we've had ours close to 2 years and it pulls our 28rsds without any problem at all. Of course it guzzles gas but we don't use it too much 'about town', only when we have the whole crew...... At least if you 'go big' and then decide to upgrade the tt, you'll be prepared!


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## Oregon_Camper

Hey...I'm here to tell you my 6.0 2500 is a GREAT TV. I get about 10MPG and have NEVER NEVER NEVER had any problems towing my 28RSS up and over the PNW Mountains (which is no small task)

Unless you think you're going to jump to a 30+ footer Outback in the future, save the extra cost and the extra gas money...go with the 6.0.


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## California Jim

This can be a subjective thing I'm sure, and I say this because I am somewhat disappointed in my 6.0 Suburban that also has 4:10 gears. I have already been in situations with this combo where I have my foot mashed all the way to the floor and just barely, and slowly got the job done.

I was in one campground (1000 trails Idyllwild, CA) and almost couldn't make it up the main entrance hill. 1st gear, gas pedal to the floor, almost didn't make it. It was most disappointing because this was my exact experience in this campground with the same trailer and my old 99 5.7 liter Suburban. I thought that surely it would be better. But no.

The 6.0 is a typical small block engine that needs to rev it's fool head off to make enough power to get the tough jobs done. In my experience It does do the job, just not in any kind of impressive fashion. If you loose your speed climbing large hills and need to slow or stop, you're pretty much toast. This has also been my experience climbing "the Grapvine" here in California with my new 6.0 Burb.

I really hoped for more since Chevy no longer offers the 8.1 in the new Burbs. After spending a bunch of money on this SUV I must honestly say that I am disappointed with it's power. It's beautiful, stable, greatly comfortable, and otherwise a pleasure. But no power improvement above my 99 5.7 Burb.

You're perspective/results may vary.


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## Oregon_Camper

California Jim said:


> This can be a subjective thing I'm sure, and I say this because I am somewhat disappointed in my 6.0 Suburban that also has 4:10 gears. I have already been in situations with this combo where I have my foot mashed all the way to the floor and just barely, and slowly got the job done.
> 
> I was in one campground (1000 trails Idyllwild, CA) and almost couldn't make it up the main entrance hill. 1st gear, gas pedal to the floor, almost didn't make it. It was most disappointing because this was my exact experience in this campground with the same trailer and my old 99 5.7 liter Suburban. I thought that surely it would be better. But no.
> 
> The 6.0 is a typical small block engine that needs to rev it's fool head off to make enough power to get the tough jobs done. In my experience It does do the job, just not in any kind of impressive fashion. If you loose your speed climbing large hills and need to slow or stop, you're pretty much toast. This has also been my experience climbing "the Grapvine" here in California with my new 6.0 Burb.
> 
> I really hoped for more since Chevy no longer offers the 8.1 in the new Burbs. After spending a bunch of money on this SUV I must honestly say that I am disappointed with it's power. It's beautiful, stable, greatly comfortable, and otherwise a pleasure. But no power improvement above my 99 5.7 Burb.
> 
> You're perspective/results may vary.


Still the Vortex?

I'm shocked by this information. I've been on some large inclines, and have not experienced a problem with power....and I dry camp, so I'm always towing everything for the trip, plus a full tank of water in the Outback.


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## Carey

If you want a 6.0 to run with the 8.1 get the 2008 Suburban with 6 speed auto. The previous 6.0 Subs had the old 4 speed.. Having the 6 speed makes all the difference. It has a much deeper 1st gear and is closely matched to he 6.0 torque.

There has been several tests done with the new 6.0 and 6 speed versus the 8.1 and Ford V10. The new 6.0/6speed runs right with the 8.1 and fords v10.

It is a very impressive combo only if it has a 6 speed.. If you cant get the 6 speed, get the 8.1..

Carey


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## johnp

I believe the old saying goes "There is NO subsititution for cubic inches" I really think GM dropped the ball by scraping the 8.1 I had that beast in my 2500 Avalanche and loved it the steeper the grade or the bigger the trailer it pulled it with ease. Go with the 8.1 yeh it burns a little more fuel but it never lacks for power.

John


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## Scoutr2

Oregon_Camper said:


> This can be a subjective thing I'm sure, and I say this because I am somewhat disappointed in my 6.0 Suburban that also has 4:10 gears. I have already been in situations with this combo where I have my foot mashed all the way to the floor and just barely, and slowly got the job done.
> 
> I was in one campground (1000 trails Idyllwild, CA) and almost couldn't make it up the main entrance hill. 1st gear, gas pedal to the floor, almost didn't make it. It was most disappointing because this was my exact experience in this campground with the same trailer and my old 99 5.7 liter Suburban. I thought that surely it would be better. But no.
> 
> The 6.0 is a typical small block engine that needs to rev it's fool head off to make enough power to get the tough jobs done. In my experience It does do the job, just not in any kind of impressive fashion. If you loose your speed climbing large hills and need to slow or stop, you're pretty much toast. This has also been my experience climbing "the Grapvine" here in California with my new 6.0 Burb.
> 
> I really hoped for more since Chevy no longer offers the 8.1 in the new Burbs. After spending a bunch of money on this SUV I must honestly say that I am disappointed with it's power. It's beautiful, stable, greatly comfortable, and otherwise a pleasure. But no power improvement above my 99 5.7 Burb.
> 
> You're perspective/results may vary.


Still the Vortex?

I'm shocked by this information. I've been on some large inclines, and have not experienced a problem with power....and I dry camp, so I'm always towing everything for the trip, plus a full tank of water in the Outback.
[/quote]

Jim has a 2007 engine, re-designed to meet the 2007 EPA requirements. You have the 2006. Jim's pumps out fewer particulates (but the same amount of CO2), but yours has more power. Granted, it's only a few horses, but sometimes that is a big difference!

Mike


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## Carey

Mike, the 2006 6.0 Suburban had 335 hp and 375 tq. The 2007 6.0 Suburban had 352 hp and 383 tq.

The 2006 and the 2007 both had the same 4 speed tranny... The 2007 should out pull the 2006.

Again if you want close to 20 mpg for gas mileage but have the pulling power of the 8.1 buy the new 2008..

If you cant buy new but want tons of power get the 8.1. and get 1/3 less mileage than the 2008 6.0 w 6 speed.

ps the LT3 and LTZ offers 366 hp in 2007 as an option...

Carey


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## ssrrchase

Thanks everyone! Great info. I don't know the year of the 6.0 but the 8.1 is a 2006 with 20,000 miles. We go look at them tomorrow. I'm leaning toward the 8.1. We are heading to Destin, Florida from CA over July and the 1500 Sub is just too tired for the trip.

The begining of the end for the 1500 I'm trading in was last summer where we left Tombstone, AZ and dashed across the desert where the temp kept rising till it maxed out at 121 degrees! We then headed up to 1000 trails at Idyllwild, CA (because it was cooler at 95 degrees) with an already hot tranny and it didn't like it too much. The Sub actually handled the trip very well. We decided to head home to Hollister, CA via 101 along the coast were it was 60 degrees cooler at 61 degrees and the kids complained it was too cold! Anyway, we had the tranny flushed and new fluid put in it. Dodged a bullet and will NEVER cross the desert again like that. It seemed like any way I chose - Interstate 40, 10, or 8 it was the same temp according to the weather channel. I did fill the water tank in the trailer, had 4 cases of water in the Sub, and dumped A LOT of ice down the toilet....

Anyway, thanks everyone!
-Steve


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## Carey

Good Luck!

Just want you to know the 8.1 is in a class of its own until gm offered the 6 speed behind the 6.0 in the 2008 Subs.

There are no real comparision from the old 6.0 with 4 speed to the 8.1 with allison 5 speed... 8.1 will trounce the 6.0...

That 8.1 will cost ya when running around empty, but when towing, the two will be within 1 mpg or so of each other..

If you can call this your second vehicle and have a high mpg car to get around town in, what the heck get that big ole 496 big block!

Carey


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## Camper Man

I have been very happy pulling a 26RS with the Vortec 6.0L / 4.10 axle in my "Chopped 'Burban." Of course, the 26RS is somewhat lighter than many of the other trailers I see listed in the signatures in this thread.

Yes, you do have to rev the 6.0L. It develops max torque at 4,300 RPM but it will spin there all day long and maintain speed with a loaded 26RS up the longest grades we have anywhere in the East. I remember the first time I peaked the summit at Thornton Gap on US 211 West in the Shenandoah Mountains ... absolutely one of the high points of my Outback experience!

My perspective: A Vortec 6.0L / 4.10 combo would be a great match for your 26RS.


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## ELSEWHERE

ssrrchase said:


> Hi all - I need some input&#8230;. I pull a 26rs with a 1500 Suburban now. I have a chance to upgrade (which I'm taking) and my choice is between a 2500 Sub in either the 6.0L or 8.1L engine. So all you 2500 Sub owners and those in the "know" - which one? Is the 8.1L overkill for a 26rs?
> 
> Does anyone know MPG towing and not towing for both the 6.0L and the 8.1L. Is there a big difference? I expect 10 City/12 Highway/9 towing on the 8.1L. Is that close?
> Any advice and help would be greatly appreciated.
> 
> Thanks,
> Steve


You didn't say what motor and gears you currently have. A 5.7L? 3.73 or 4.10 gears? I've heard a lot of people say there was a big difference between the "old" 5.7L and the "new" 6.0L.

I've noticed in a lot of threads there is no mention of the difference between the 2007 and 2007 1/2 6.0L motors. I quite often wonder, when someone says "2007", which model/engine they are referring to. The 6.0L that came out in the "new body" 2007 1/2 2500HD GM trucks was changed from the 2007's. With the motor changes and the new 6-spd the tow ratings increased. My 2008 (same as 2007 1/2) GMC 2500HD ext. cab, 6-spd., long bed with 4.10's is rated at a ball hitch trailer towing capacity of 12,200#. I've always been a believer in Chev big blocks but I think this new 6.0L with 6-spd is capable of holding it's own very well in towing capabilities. Around town I have to really soft pedal it to get 11 mpg. I haven't taken any non-towing road trips so I don't know the highway mileage. I'm currently on a trip towing a 27RLS with a Harley loaded in the truck bed and a total gross of 15,200#. Mileage sucks! If I run flat country I can just break 8 mpg doing around 60 mph. If I have any passes to go over, which I've done a lot of on the west coast and S.W., mileage will drop to just over 7 mpg. Seems like much over about 65 and I really start using gas.

If you're talking a 2007 or older Burb with the 6.0L and 4-spd I would think you would definitely need 4.10's for any kind of performance. With the added torque of the 8.1 you'd certainly have a bigger cushion for towing and would probably be happier.


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## California Jim

I was seriously bummed when they came out with the 6 speed tranny for the 6.0 RIGHT AFTER I BOUGHT MY BURB! So you now have this one and only DOG year of the 2500 suburban, and I OWN IT







They should have kept the 8.1 in play for one more lousy year until the 6 speed was ready to go. YOU STINK GM. Yeah, I'm bitter.


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## Rubrhammer

California Jim said:


> I was seriously bummed when they came out with the 6 speed tranny for the 6.0 RIGHT AFTER I BOUGHT MY BURB! So you now have this one and only DOG year of the 2500 suburban, and I OWN IT
> 
> 
> 
> 
> 
> 
> 
> They should have kept the 8.1 in play for one more lousy year until the 6 speed was ready to go. YOU STINK GM. Yeah, I'm bitter.


So get a 6 sp and put it in. less money than trading and you wind up with a great towing machine. 
http://cgi.ebay.com/ebaymotors/Chevy-Silve...96585QQtcZphoto


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## California Jim

At some point that may not be out of the question. But while she's new and under warranty....gotta ride it out.


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## ssrrchase

Ok, we took the plunge and bought the '06 8.1L 2wd Sub. On the way home (50 miles of hwy driving) the computer said we were avg. 16+ mpg at 70 and 17.5 mpg on a 12 mile stretch driving 55 mph . I thought I was going to get 12! I told my wife something has to be "wrong" and as soon as I drove into the driveway I lifted the hood to make sure it was the 8.1L and not a 5.3L. So, I'm very happy with this "non-towing" mileage. Can't wait to tow the trailer to see what it does.

-Steve


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## tdvffjohn

Good Luck









John

PS, we do require a pic, ya know


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## johnp

ssrrchase said:


> Ok, we took the plunge and bought the '06 8.1L 2wd Sub. On the way home (50 miles of hwy driving) the computer said we were avg. 16+ mpg at 70 and 17.5 mpg on a 12 mile stretch driving 55 mph . I thought I was going to get 12! I told my wife something has to be "wrong" and as soon as I drove into the driveway I lifted the hood to make sure it was the 8.1L and not a 5.3L. So, I'm very happy with this "non-towing" mileage. Can't wait to tow the trailer to see what it does.
> 
> -Steve


Thats because you were babying it. Soon you will begin to have funny with the 8.1







or put dual exhaust







on it and long behold the beast will come out and you will get about 9mpg







enjoy it its a great pulling machine. The only thing I don't miss about the Avalanche was thirst of that motor which is directly related to the right foot.

John


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## Oregon_Camper

ssrrchase said:


> Ok, we took the plunge and bought the '06 8.1L 2wd Sub. On the way home (50 miles of hwy driving) the computer said we were avg. 16+ mpg at 70 and 17.5 mpg on a 12 mile stretch driving 55 mph . I thought I was going to get 12! I told my wife something has to be "wrong" and as soon as I drove into the driveway I lifted the hood to make sure it was the 8.1L and not a 5.3L. So, I'm very happy with this "non-towing" mileage. Can't wait to tow the trailer to see what it does.
> 
> -Steve


Congrats on the nuew Suburban....that is a great TV.

Got any pictures for us?


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## BoaterDan

ssrrchase said:


> Ok, we took the plunge and bought the '06 8.1L 2wd Sub. On the way home (50 miles of hwy driving) the computer said we were avg. 16+ mpg at 70 and 17.5 mpg on a 12 mile stretch driving 55 mph . I thought I was going to get 12! I told my wife something has to be "wrong" and as soon as I drove into the driveway I lifted the hood to make sure it was the 8.1L and not a 5.3L. So, I'm very happy with this "non-towing" mileage. Can't wait to tow the trailer to see what it does.
> 
> -Steve


Ruh roh. Did you verify it has 4.10 gears? I'm thinking that has to be with the 3.73 option. If so, the specified trailer capacity is 10,600 rather than 12,000. Maybe that's better in your case.


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## ssrrchase

Yeah, it's the 3.73. I figured 10,600 pounds was plenty for me (going from 7,200 #'s). I don't anticipate getting any bigger than the 26 foot trailer we have now. (I don't really want to pull anything longer







)

-Steve


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## battalionchief3

We have 2500 burb with a 6.0 and the 4 sp auto at work and I was also very disappointed in the power. The prior model year had WAY more snap in the engine.

We own a 8.1 with 4:10 gears and an older 4L80E 4sp auto and it pulls the 30ft camper up a 9% grade throught West VA like a champ. 60mph in 3rd and I still have pedel to pass. We get about 8mpg towing and 11/12 around town. But it is an extra vehicle and sits most of the time so we dont pay out the nose every day for gas. If you can swing it get the 8.1.

No replacment for displacement.


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