8.1 & Allison?
 

Pros & Cons of BBC 8.1 with Allison trans. Looking at a 02 2500 with an 8.1 and Allison trans for pulling my car trailer and Sheds/Gazebos Ect. Anyone have one that can chime in with the good and bad details. Other then it being a Pig on gas is there any other major issues.

Can I ask why you wouldn't go duramax?

Hard to find one that is clean without rust, or haven't been hacked, modded and beaten to the ground. I like to drive with the windows down, and that smell after a while gets to me. The ones that are still in good shape are big money. For what we do I don't think a diesel is needed. The sheds are big but they don't weigh much. My 1500 6.2 was perfect but the truck was to nice to be a work truck. 6.0s would work but i found a clean 8.1 with 75k for cheap and I know the owner and its history.

No.

Get a 2500HD/6.0 gas, if you must. It will have 4.10 gears so should tow better then your 6.2/3.42 gears.

6.0 are backed with a 4L80 or 4L60? I want the truck downshift in tow/haul like my 6.2 did. Saves the brakes and makes going down hills that much easier. I know the Allison trans does down shift on decel.

If 2008+ the 2500 comes with a 6L90E. If 2007 and below has a 4L80E, IIRC.

Trans changed with the body style in the 3/4 ton. The 6 liter/4L80E tows like a mushy pedal pig with a lot of weight and do poorly on fuel.

The 8.1 was known to burn tremendous amounts of oil between services.

The 6 speed 6L80E (or is it actually the 6L90E) with the 6.0 tows much nicer and does a phenomenal job of engine braking.

I always get tied up with the 2007.5 and just say 2008 and newer.

My 6.2/4L70E/4.10 gears tow great... mileage certainly sucks.

Hmmm. I might be bashing the 6.0/4L80E a bit harder than I should. It defiantly tows way better than my 5.3/4L60E with 3.73s but it's a night and day difference between the 6.0/6 speed and 4 speed when both have 4.10 gears.

I had one. Towed like a beast. I don't remember it being much worse mpg than my current 6.0. Mine used1 qt every 4k miles. I have heard horror stories about oil consumption. I'm sure you know but check the brake lines on those Chebby's.

I heard they use alota oil and get like 8mpg I would go 6.6 duramax if u keep an eye out long enough you should be able to find a decent one. just my opinion

Duramax is outta the question unless it's super cheap and clean. Not a fan of the coal. Gas mileage is not an issue. Low end power and braking are the main concerns.

Brake in the Allison is nice! I just bought a 15 GMC with a 6.0 and it has a grade braking button. Haven't used it yet but I assume it works like the Allison.


Nothing pulls like a diesel but unless you need the mpg its a waste of money.

My truck all stock with a cat doesn't smell much at all. I think the allison is great though, tow haul mode really slows the truck down with a load. If the truck was well taken care of, I don't see it being a nightmare. Any of the gen 3's can drink oil. 8.1 should have good low end grunt like you want.

https://southjersey.craigslist.org/cto/5485683103.html

If that truck isn't rusted out......:)

Thanks for the link... I'll check this one out.

My brother has a 2004 or 2005 extended cab duramax with right around 100-110k on the clock and I'm pretty sure he's looking to sell it.
The truck is dinged and dented, nothing outrageous but it's not the prettiest. Needs cab corners, outer rockers and a rear bumper along with brake lines. It has a 5th wheel. Single axle rear.

It is in a fleet of work trucks. I'm almost certain he would sell it for 8 grand. I don't think this specific truck was one of his plow trucks.


If you are the slightest bit interested I can ask him and get pictures.

See, my problem is I would want a diesel Denali, and there goes the price thru the roof...

This sounds like the typical 8 grand pos :rofl:

That or a duraburb :drool:

Just buy a later 05-11 model duramax and be happy.

thats what I had ordered before I got my 5.3 silverado ltz and the broker screwed the deal up so i told him to f off... then i found this truck at the dealer and really liked it but i still wish it was diesel

I thought lly was mid year 04?

Yes, but late model year 05 gets you an LBZ for LLY pricing and the fancy upgrades like steering wheel controls and better tow mirrors.

Nothing wrong with 04-early 05 though.