Jump to content

2004 Gmc 2500hd 8.1

Twistgrip

Recommended Posts

Twistgrip Enthusiast

Twistgrip

Posted
Posted

Hey guy's newbie here, I did a search on the 8.1 and found a lot of info but would like a little more. I'm looking at a 2004 gmc crew cab 2500hd with the following toys on it,

8.1 auto (not sure if its a allison or not)

65000 miles

rhino lining

K&N air cleaner system

Megnafow mufflers

loaded, xm, mirriors, windows ect.

285 tires

great shape, runs sweet, drives sweet

ANY info on this beast would be great! $19000.00asking

Am i missing something? seems like a good deal.

2001bigblockburban Enthusiast

2001bigblockburban

Posted
Posted

First off, welcome to GM-trucks. That truck sounds like a find these 8.1 are getting harder and harder to find. If it has tow/haul mode and an OD crossed out on the column shifter than it has the allison trans behind it. I love both the 8.1's we have. By far the allison is the best for towing in the HD(the burbans no slug but the allison makes all the difference). Dont expect good gas mileage out of it lucky to get 10city/13hwy.....but normally 9.5/12. It seems everyone has oil consumption, depending on the driving habits usually about a quart every 3,000 miles. The price to me seems a little high. These bigblocks should be pretty cheap with how much gas cost. For comparison I got my 04 extened cab short bed 4x4 LS (35k miles) for 19g's almost a year and half ago from a local dealer (it had been there for almost 4 months). But a CC is defiantly going to bring more money. Good luck with the truck you'll love the power and it will pass anything on the street but a gas station.

J

ws6_guy Senior Enthusiast

ws6_guy

Posted
Posted

Sounds like a great truck, just hope your not expecting it to be a suitable daily driver. Cause you will be making friends with the gas station people alot :lol:

 

The price is kinda high though, I say $17,000 its more worth. The fact that it has one of then K&N intakes..... well... you can put a better one in :)

 

If you get it post pics! & i'd love to hear how that thing sounds.

kmdmb New Member

kmdmb

Posted
Posted

Just traded my 04 cc 8.1 in today. Going to try to sell it while waiting for the new one. I'm asking 19 with 37,000 miles, so that sounds a little high for that one.

Twistgrip Enthusiast

Twistgrip

Posted
  • Author
Posted

Thanks for the responses guys, so the 8.1 is a good motor aside from the bad gas miliage? Is there anything else I should be aware of?

bert55441 Enthusiast

bert55441

Posted
Posted

I'm not sure about years but I have a 2002 GMC Sierra with the 8.1 and it had a bad crank position sensor. Thats how I found this site when my truck kept having intermediate stalling with no codes. When we changed it the dealer told my dad that gm changed the design of it 3 times so I hope gm finally got it right and this one last me. :D

Haulin' 8.1 Enthusiast

Haulin' 8.1

Posted
Posted

I agree with the others, my truck was very similar to that one with 50K on it and I paid $1,000 less. All 8.1 Silverado automatics are Allisons. The 8.1 SUV's have the 4L80E automatic. The failure prone crank sensors were 01-02 model years. You're looking at a very comfortable, dependable, and capable pick-up truck. All you need to do is look it over carefully to see if it's been taken care of. Take the oil filler cap off with the engine running and look for any smoke coming out, there shouldn't be any. Smell the transmission dipstick, if it smells burned that's bad. Drive it over bumps and listen for loud popping in the front steering, the pitman and idler arms are quick to wear out but they are easily replaced. If you can live with the 10 MPG and get the price down a bit it's a great truck.

 

Vernon

JayV83 New Member

JayV83

Posted
Posted

I just bought an 05 crewcab 2500hd with the 8.1 and allison with 4.10s, it has dual magnaflow exh, spray in liner, remote start, 26,000 miles, leveling kit, 285/75/16 tires, airaide cold air intake, 5 year 100,000 mile bumper to bumper warrenty, and a couple of other little goodies for $20,000

Daubs Enthusiast

Daubs

Posted
Posted

I've got an 04 2500HD crew with the 8.1. True, they only came with the Allison tranny -- the 5 speed version. Check and see what rear end it has...either 3.73 or 4.10.

 

Mine is getting consistent 10-11 MPG city, but not in winter months. All that warming up, sitting drops me down under 10 MPG. Highway I've been known to get 12-14 depending on lots of factors.

 

Love my truck and have 0% financing on it, so I'm going to keep driving every day for a long time. Also have ext warranty that will cover me until 10 years, 100k miles, with zero deductable.

 

I've heard the 6.0's don't get that much better MPG, so figured I would be happier with the Big Block. I've never been disappionted. Yes, doesn't do great on fuel...but does better than my Dad's old 1976 K20HD regular cab long box. That truck got 6 MPG city OR highway! Getting 10 MPG from heavier truck with 496 cubic inches and all the comfort goodies (leather, XM, on-star, heated seats, etc.), well, I'm not going to complain about the price of gas one bit. It is what it is...and I'm driving what I'm driving. Nuff said.

 

Another thing to think about when considering the 8.1...you are driving the biggest production V8 ever put into a truck! And they aren't making them any more...

Raylar New Member

Raylar

Posted
Posted

If you have questions about the 8.1L engine, we at Raylar are kind of considered the "word" in 8.1L engines and upgrades. You can also visit our website www.raylarengine.com might peak your interest.

Regards

Ray @ Raylar :lol:

 

 

 

 

 

Thanks for all the replies guys, and being they don't make the 8.1 anymore is it hard to get parts for?
Riverjet502 Enthusiast

Riverjet502

Posted
Posted

Not meaning to hi-jack this thread but since the 496 was killed off by the tree huggers.. There is the option with a littlle wrenching time to drop in a ZZ502/502 crate motor. Been running one of these for 8 seasons now and that will put a grin on yer face...

Twistgrip Enthusiast

Twistgrip

Posted
  • Author
Posted

Hey guys, just wanted to say thanks on all the info about the truck. I pulled the trigger today and bought it. I will pick it up tomorrow :D:mad::D it also has the 410 rear end!

  • 10 months later...
REV353 Enthusiast

REV353

Posted
Posted

I have the 2002 GMC 2500 Hd with the 8.1. I can not seem to get better than 8.9 mpg on the HWY. I have tried injector cleaners and different brands and octane of gas. I changed everything over to Amsoil 10 months ago and put there high flow airfilter in, that is it, any ideas.

Archived

This topic is now archived and is closed to further replies.

Go to topic listing

  • Latest Articles

  • Posts

    • Atlas
      Wow I'm in a pickle. (Broke down truck) and a story.

      By Atlas · Posted

      My office is slowly filling with Blazer parts. Getting ready to do the big bang of repairs. Intake (second time), water pump, radiator, hoses, and I'm going to re-seal the timing cover where someone went hog wild with silicone. Might as well, because I don't think that's done right.   There's a local tow yard that I didn't realize also has quite the inventory of junk vehicles. This is an old school junkyard. No waivers. Cash only, you were never here if anyone asks. Don't piss off the owner, or you'll end up in the back of one of those cars, headed for the shredder. And if you see something, don't snitch. Cars stacked double high, wasps nests, trip hazards and junk everywhere. I found a few little odds/ends for my Blazer. The $20 I spent was worth the experience alone. But I was never there. What yard?   I officially love/hate this truck. It's so out of my wheelhouse, roughest vehicle I've ever owned. Every. single. repair. -is so hard-fought, everything that can go wrong, goes wrong. Currently in a hate phase, and kind of wish I was closer to sending it down the road with a lucky new owner, to be honest. Preparing for the day when I tear into this thing...lots of pre-funk with Ibuprofen.   Rock Auto sent me a bad reman rear wiper motor. It was a bear to install. The tailgate in these things has about eleventy-billion fastners and pieces and things that need to be uninstalled/moved just to access the shoddy rear wiper motor. The casing on mine was cracked clean through, btw. Nice, GM, nice. SO I got this new motor installed, hit the switch, I see it wig-wag (without the arm installed) and think I'm golden. Reassemble everything. With the wiper arm installed I gave it one final test. Time to clean up and take the other half out to dinner, collect a paycheck, right?   Nope. I hear the plastic worm gear stripping as the arm hung up. Just like my broken motor. Weak/old and shredding itself internally. I can assist the arm and the range of motion is normal, and it parks correctly. It just doesn't have the poop to actually sweep the arm with a blade on it. Oh, hell. Turned the key off and shut the shop door behind me. I get to do that over again, too.
    • BlueV8
      AFM Disabler Question

      By BlueV8 · Posted

      A complete delete is the most thorough mechanical solution, but it is also major engine work. On a quiet truck that is still under extended warranty, opening the engine purely as prevention is difficult to justify. A plug-in disabler stops commanded cylinder deactivation, but it does not remove or repair the collapsible lifters, so it should not be treated as failure insurance. I would keep the oil full, document the maintenance, and have any persistent tick, misfire, or loss of power diagnosed promptly. If the engine eventually has to come apart, that is the logical time to compare an OEM-style repair with a complete delete. The right choice depends on the truck’s symptoms, warranty status, expected ownership period, and whether the engine already needs to be opened. We explain that decision in more detail here—full disclosure, this is our own guide: https://www.bluev8.com/blogs/news/do-you-actually-need-an-afm-disabler   One exception: some 2021 L82/L84 trucks have RPO YK9, meaning cylinder deactivation was already disabled in the factory ECM; on those trucks a plug-in disabler is redundant, although the AFM/DFM hardware remains inside the engine.
    • mark249
      Help purchasing a touch screen digitizer

      By mark249 · Posted

      Brought my 2015 Colorado into the dealership to check my touch screen issues, had that ghost touch thing happening. They said I needed a new touch screen and they could either order me one for $500. The lady at the service deck was nice enough to tell me I could order a touch screen online for less, she did stipulate that the touch screen had to be factory OEM, you can't pair an aftermarket screen to my radio seeing it was 2015, it had to be a GM factory OEM only. I found a few on Amazon and Ebay by the numbers on the back of the old screen, DJ080PA-01A GM# 22740886, Some said "OEM" in the description and others just said "Replacement". Would a replacement be the same as a OEM as long as it had the same numbers on the back of the screen? In some of the descriptions they also show different brand names but same numbers, is that an issue?  
    • Donstar
      Navigating senior years.

      By Donstar · Posted

      I have both but typically use the 4 legged walker (wheels on front, ski's on back).   The four wheeler is starting to be used on "longer" outdoor walks.  The 4 legged walker is particularly helpful in practicing good walking posture.  Both of my knees are at different stages of recovery and I'm trying to not develop poor habits.  I can actually manage with a cane but it's very difficult not to favor one leg over the other.  My PT recommends I continue with my 4 legged walker for a while.  Yesterday was four weeks since my last knee replacement and I'm excited about my progress to date.  It has been a hell of a rough journey so far but it is exciting to witness  systematic and continuous improvement.  I went for years watching the decline of my "mobility".  It seems that everyday now I am alerting my wife to something I can do now that I couldn't a day or two ago!  I encourage anyone facing the prospect of knee replacement to share any concerns with others who have had the surgery.  It isn't an instant fix but rather is a considerable amount of short term pain for long term gain.  Recovery time and pain levels vary for individuals post surgery but the end results are typically very positive and I've never encountered anyone regretting having had the surgery. 
    • diyer2
      AFM Disabler Question

      By diyer2 · Posted

      The lifter issue can be dealt with by shorter oil changes and quality oil IMO.

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...