Chevy Silverado/GMC Sierra's w 8100/Allison

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Comments

  • 4964me14964me1 Member Posts: 15
    Mine started knocking at about 1000 miles. Thought I was nuts, but I've got 2500 miles on it now, and it's definitely getting louder. Oil pressure is only ~20psi hot, and I've used over a quart of oil. Babied it for the first 1000 miles. I just can't bear the thought of my engine sitting in some shop in a million pieces with some dude looking at it while the ash falls off his cigarette on top of the crankshaft and says "Looks ok to ME..., puts it back together and says "Put 20W50 in it, that will quiet it down" and 3000 miles down the road it's the same thing all over again.
    Anybody taken theirs in? What's GM saying about this? Engines aren't supposed to knock, man.
  • 2500hd2500hd Member Posts: 11
    Son of A *!#!*!!! I really had my heart set on one of these bad boys . :(
    Anybody know of any good Super Duty Forums?
  • woolybackwoolyback Member Posts: 45
    (eric2001) if you want to check out the location of the filter and magnet etc. you could go to the Allison web site they have an excellent write up and pictures on the maintenance and anything else you would like to know. This URL should take you right to it but if not just type in the first part to the .com and then go from there once you get to the site.

    <http://www.allisontransmission.com/documents/product/publications/pubs/OM3063EN.pdf >


    I think I've got my air conditioner problem taken care of (I hope). I took in for the 3rd time and this time I left it running in front of the service dept. I had been on the freeway on the way home and it quit on me again so I drove it right around to the dealers. I told them I wanted a mechanic to look at it while it was still not working and they got one out there. He ended up replacing the cycling switch. So hopefully it's fixed...won't know for sure until I've tested it out.


    Checked on the price of my filter change and the filter was $23.85 but the guy behind the parts counter told me that the new price will be $14.


    GMC tried to sell me a 5 year extended warranty.. sent me a letter in the mail, but you have to read the fine print.

    It really is only a 2 year warranty as the 5year starts at zero miles, it isn't tacked on to the end of your 3 year warranty like it should be.

  • eric2001eric2001 Member Posts: 482
    Thanks for the link. I had already printed that manual out a month ago, trying to find the specifics on the tranny brake (couldn't find them). I guess I had better start reading through it again.

    4964me1: I first noticed the start-up knock @ 1300 miles, didn't make me too happy, but I guess I will at least get the extended warranty out of it. Now to schedule a hearing session with the service department...
    -Eric
  • mrurlmrurl Member Posts: 116
    20 psi oil pressure is way low. Everyone else around here is reporting 45 - 60 psi at idle and at 1000 rpm. I would have that looked at.

    Peter
  • 4x4man4x4man Member Posts: 222
    Well, changed the oil to synthetic over the weekend....but...alas...the great knock is still present. Oh well, at least I am giving my engine the most protection available at this time....

    By the way I had a bit of a problem trying to grease the lower ball joints. I bought a grease gun with the rubber hose as suggested by others, but both the lower ball joints wouldn't accept grease, it just kept making a mess. The tie rods and upper ball joints all took grease no problem...any suggestions anyone???
    2001 2500HD 4x4 with 8.1/Alli

    Bob
  • n75v111n75v111 Member Posts: 243
    Wooly - thks for the Alli Operator's Manual link-

    Question - Which Alli does the HD's have - 1000, 2000 or 2400 Series?

    What is the AC Filter No.?

    ($23.85 or $14.00) Will look for replacement brand -- Alli does't give a filter no.! Oh! bet I need to look in the vehicle owners manual--

    Alli OM3063EM say to DRAIN the trans.
    Just to change the FILTER?? Is that right?
    How many Qts of fluid does that Drain??

    Thks -- 75v
  • ryanbabryanbab Member Posts: 7,240
    hd's have the allison 1000
  • 4x4man4x4man Member Posts: 222
    Ryan is right, they put the Allison 1000 series in our HD's.
    The part number for the external spin-on filter is 29537268. I assume that is an Allison number, I picked that up from either the dieselpage or pickuptruck.com and just jotted it down so I hope it is right as I haven't verified it yet (only at 3,000 miles)

    From what I read in that service manual for the 1000 series you just have to change the external filter at 5,000 miles, no mention of a fluid change at 5,000 miles.

    Hope this helps...

    Bob
  • eric2001eric2001 Member Posts: 482
    According to the Alli manual, a refill of the trans is 10.6 quarts, but this is an approximate. It all depends on how much you actually get to drain out of the lines, torque convertor, trans itself... What are planning on putting back in it, Dex3 or the TranSynd?

    -Eric
  • woolybackwoolyback Member Posts: 45
    When the dealer changed my filter they just topped off the fluid, it couldn't have been much as they didn't charge me for it.
  • gmcgt1gmcgt1 Member Posts: 3
    Just returned from a 2850mi round trip to Yellowstone via Mt Rushmore. Trip fuel mileage was 8.25 mpg towing a 7000lb 5th wheel and 4 adults, we did travel empty about 200mi. On flat grade the 8.1 was getting 10.1mpg (75mph when we werent doing 80)!! The 8100 just wants to run and a little 5th wheel is almost an insignificant load for the beast. Traveled at elevations ranging from 3000 ft to over 10,000 ft. Pick up had more power than any of those switchback pases could handle. Allison was impressive when traveling down grades, AC was colder than any of us could tollerate. It helps to keep the AC set on recirc mode to get the absolute frigid output. Used 1 qt oil for the entire trip. Currently the 8100 gets 13.5 empty with the cruise set at 75 mpg.
    For the individual that inquired about Eagle Aloy wheels. I have a set of Eagle 115's, they run great with no vibration.
    gt
  • owenm1owenm1 Member Posts: 29
    Anyone found an online place to buy the Allison filter? (I'm overseas)
    I have the knock that all are talking about, I'm thinking about unloading this rig before the word is everywhere. (2300 miles) I have the only 8.1 over here at the moment.
    Also, anyone need a set of front Huskyliner front black mats for a 2001HD ext cab? I have an extra set. email me at: omcniff@yahoo.com if interested.
  • 1i2cu1i2cu Member Posts: 32
    Do you think 'Royal Purple' is worth $6.70 a quart ? That would be about $50 plus for a OLF ?
    Or try Mobil 1 ? Stick with Valoline 5/30w?

    Any wine drinkers out there ?

    Just had a bottle of Fess Parkers Chardonnay, Marcella's Vineyard. Very refreshing, slight sweet taste, butterly to the palate. MMMMMMM!!
  • owenm1owenm1 Member Posts: 29
    sounds great! Maybe we should bring a bottle when requesting engine knock evaluations!
  • 4x4man4x4man Member Posts: 222
    I don't know anything about Royal Purple, I switched to Mobile 1 at 3k, but the knock didn't go away. I'm probably going to make an appt at the dealer to start the worthless soak on the engine so I can get the ball rolling to getting my free warranty when I start to complain.

    Bob
  • eric2001eric2001 Member Posts: 482
    Is what happens to the "stuff" (engine decarbonizer & carbon buildup)? How much slips past the rings? Does it contaminate the oil? Is it possible it all just sits there, and burns after start-up? If so, any issues with plugging the cat conv?

    Also, it seems that everyone that has had this done, gets the knock back a few thousand miles later. Does his then become a maintenance issue> lube/oil/filter/decarbon pistons?
    -Eric
  • 4x4man4x4man Member Posts: 222
    I agree with your question, but it seems as though the only way you can complain and get the free warranty is have the dealer confirm you have the knock and have this soak performed first. I still don't understand how carbon on the top of the pistons can make this knock happen at such low mileage or even at all...guess I still don't fully understand what's going on with this, except that it is there.

    That is a good question, for those that have had the soak done on their engine, did the oil need to be changed afterwards?? Sure would pi$$ me off if it did as that would be 26 bucks for the synthetic oil down the recycling tubes!!

    Bob
  • 4964me14964me1 Member Posts: 15
    Well... I called 3 different dealerships, and here's what they had to say.
    1. "Well, the 8100's ALL knock when you start them up."
    2. "GM says that a quart of oil every thousand miles is "normal oil consumption"

    Correct me if I'm wrong here, but experience has taught me that if your engine knocks when you start it up and burns a quart of oil every thousand miles it's not going to last very long.

    A friend of mine builds engines for the local race teams, dirt track circuit... He was helping me build an engine for my old Cutlass and he gave some helpful advice: "Well, if it knocks or burns oil, take it out and tear it down, because you obviously screwed it up when you put it together."

    Is the 8100 going the way of Buick's infamous 231 V-6? Anyone here interested in a class action suit?
  • cowboyjohn1cowboyjohn1 Member Posts: 125
    I have an 8.1 and it don't knock on startup and burned about 1/2 qt in 3000 miles. I'm happy.
    cowboyjohn
  • mychevy2mychevy2 Member Posts: 5
    Well I have had my 8.1 since Dec. I have 9k miles on it and it uses approx 2 quarts every 3k miles. The dealer gave me a consumption test to start tracking the use of the oil. I am planning to take it in this week to get their answer. I can not except that this should be considered normal
  • n75v111n75v111 Member Posts: 243
    6500 mi w/1000 pulling 10,500 5th wheel -- No knock. Oil consumption about 1/2 qt when pulling the 5th wheel.

    Gm's position has been for the last 30 years that a qt in 500 miles is normal- That's why i switched to Ford in '90 but now i'm back so hope gm had learned something.

    Sounds like gm 'Soak Deal' referred to here is an attempt to remove carbon elements building up on pistons.

    I would offer this- If carbon deposits are the issue they will provide hot spots in the cylindars and can cause pre-ignition which may be related to the knock being refered to.

    The root cause is to determine what is causing the carbon deposits-- they could be an issue in any engine.

    The only source for the carbon is either the Fuel or the Oil being used. The fuel blends are different from season to season and locations around the country as well as some cities require ther own blends etc. So one brand may not be the cause in one area and is in another.

    Opinions pro & con??

    75v
  • sir_colsir_col Member Posts: 25
    I would like to track the shippment of my new 8.1 2500HD to the dealer....How can I do this ....Help please...Many thanks...Sir-col
  • noobie1noobie1 Member Posts: 326
    1. Call your dealer and ask for the order number
    for your truck. It won't be a number at all but
    a six letter designation like, "DMZXNN".

    2. Call Cheverolet, 1-800-222-1020 and get
    customer service (I'm not sure which menu
    selection). Give them your order number and ask
    for your vehicle identification number, "VIN".


    3. You can use the VIN at www.bnsf.com to track
    your truck. You'll figure out how. Explore.

    Yours must have rolled off right in front of
    mine. I called today, and they said although
    mine's been built it hasn't been released yet.
    Something about still being in smog
    certification.

    Have fun, David
  • jrkracejrkrace Member Posts: 32
    Hi All I have been reading this column and am enjoying it. Here's my gripe. I ordered a 2002 GMC x-cab,6.0,sb,auto on May 20th. GM accepted order on June 13. To this day NO BUILD DATE. Not for anything I ordered this truck for plowing and I really feel it won't get here until after the snow falls.Any ideas. Thanks
  • sonjaabsonjaab Member Posts: 1,057
    Hey...If your a plow head check out
    www.plowsite.com
    Lots of plow heads over there to help
    you out on plow stuff......
    As far as truck stuff THIS IS THE PLACE !
    Try the 2500-3500 thread here too.....Geo
  • jrkracejrkrace Member Posts: 32
    The wait is killing me. Thanks for the plow site
  • ryanbabryanbab Member Posts: 7,240
    Your dealer might not have an allocation. Or something may be holding the order up (option on hold)
  • noobie1noobie1 Member Posts: 326
    ref. #775 bottom.
    I ordered my truck May 25th. The order was accepted (an allocation was given to my dealer) in the same week as yours. This length of wait is not unusual. What with "on time delivery", Ryan is right about a possible option delay. But yours should be rolling off any day. Besides, with all the "squeaks, whistles, rattles, shudders, shimmies, knocks, etc. we hear about here, I'd be more concerned about getting a good one than a soon one! Pray for a late snow and relax. It'll be here "on time".

    David
  • bigsnagbigsnag Member Posts: 394
    It sounds like the knock everyone is experiencing is similar to the piston slap that Ford owners experienced with the 4.6 and 5.4L engines. I don't think carbon build up causing hot spots and pre-ignition is a valid claim for an engine that has cold-start knock. Maybe for an engine that pings when up to temp, but not at first start. That sounds like a loose piston or maybe loose bearings in the lower end. Soaking the cylinders (and pistons) with some goop could remedy piston slap, at least temporarily, until the goop burns off. My $0.02.
  • n75v111n75v111 Member Posts: 243
    How was you trip to Nebraska??

    75v
  • 4964me14964me1 Member Posts: 15
    Mine's at the dealer today. Took it in yesterday to diagnose the startup knock/low oil pressure/oil consumption problem. Asked them to see if they could figure out why it's 3/4 inch higher on the passenger side and fix the emblems on the tailgate that were coming off. When I told them it's burning oil the guy looked at me like I was an idiot and said said "How do YOU know it burns oil?" I explained it simply: "It's got 3,000 miles on it, and it's down almost 2 quarts"
    his reply: "But how do you know it's burning oil?" I said "two quarts of oil went SOMEWHERE, and it didn't LEAK out." He says: "but how do you know it's burning oil?"... They got some real freakin geniuses working over there, I tell you. So today the kid calls me up and says "Well, I ran it, and I didn't hear anything knocking" Typical. My girlfriend heard it. My friends heard it. Even my MOTHER heard it.
    Doesn't look too promising getting anywhere at the Chevy dealer. Anyone else get anywhere?
  • growler8growler8 Member Posts: 1
    There is an interesting article that was posted under the 'Chevy HD2500 Problems' at post #52 addressing the same issues in the Corvette engines. The link to the article is:


    http://www.c5registry.com./2k2z06/page5.htm


    If I understood the article correctly, the oil consumption was based on driving habits where you would have the engine at higher RPM's with a light load.

  • bigsnagbigsnag Member Posts: 394
    Chevy is now experiencing the same problems that Ford did with piston slap. I hope the Chevy guys remember how much grief us Ford guys took over that one.
  • jblair1jblair1 Member Posts: 5
    I'm hoping somebody out there in Chevy land is a wiring Specialist. I've just purchased a Canopy for my 2500HD with an interior light. On my previous truck I had a bad habit of leaving the light on resulting in a few dead batteries in the AM. Tieing the Canopy dome light into the Battery Run-Down Protection circuitry sounds like the ideal problem fixer. Does anybody know where I might be able to easily tie into the Battery Run-Down protection wiring?.

    Also, I'm sure its not news to anyone that they "don't build them like they used to". After the first 1000 miles even the weatherstipping/sealer trims (from the bottom of the doors and inside edges of the hood) started falling of. Must have been put on before the surfaces were properly cleaned. Any guesses on whether the dealers going to give me a hard time when I tell them I want them all replaced.

    Appreciate any help anyone might be able to provide on my wiring question.
    Thanks,

    Jim
  • 4964me14964me1 Member Posts: 15
    Well, I broke down and took it in. They said they heard the knock, but they wouldn't put anything in writing. Called every Chevy dealer in my area, and here's the vote:

    Piston design: 2
    Lifter noise: 2
    We have no idea: 1

    All of them agreed that it's "normal" for GM engines to knock. I'll agree that while it may be COMMON, it sure ain't normal. One guy actually said there's a fix. They're offering to tear down the engines and replace the pistons with a new polymer coated piston, but nobody as of yet wants their engines torn apart because who knows what happens when the polymer coating wears off. According to all the service managers it's not detrimental to the engine, because GM is telling them it's "normal". (just because they all knock, that doesn't make it normal.) I managed to ask a couple of the mechanics what THEY thought and they both said "Sounds pretty ****ed up to me. I'd get rid of it." So the guys who went to automotive school and passed all the ASE certification tests think I should dump it. What do you guys think?
  • 4x4man4x4man Member Posts: 222
    Well, today I am going to break down and go into the dealer and see what kind of a BS story I will get about the knock in my 8.1. I am going to talk with the service manager first, not sure it will help any, but wanted to skip the dips that type up your service invoice and know nothing about the problems you take a truck in for...

    This is driving me up the wall now, I have read so much, so many problems, possible fixes, no fixes, blah, blah, blah. One thing I did read I think on pickuptruck.com that one guy had an oil analysis done at 12k on his 6.0L and showed high amounts of Copper which relates to excessive bearing wear I guess...so next oil change I am going to spend the 18 bucks and have one done and see what comes back. Probably have to do a couple to get a trend, but if it has high amounts of Aluminum or Copper I am gonna freak out!!!

    Will let you know what the service department tries to pull over my head as ab excuse tonight or tomorrow..

    Bob
  • 4x4man4x4man Member Posts: 222
    Well, I guess I will try again today as the service manager was out when I went down there yesterday...
  • sir_colsir_col Member Posts: 25
    Just returned from a 1600 mile trip ( LAX to SLC via interstate 15, R/T ) with my new 2002 2500HD ext cab sb 4x4 8.1,Alli, 3.73 truck. At 62mph 1800 rpm northbound 14.25 to 14.65 mpg; ( 600 miles)southbound 62mph, 1800 rpm 14.65 to 15.10 mpg. On one segment @ 70-75mph between St. George Ut. and Las Vegas 11.9 mpg. In town 10.5 to 11.2mpg. total miles on truck now = 2600, and no major complaints yet. One question what is other 8.1 hot idle oil pressure, (in gear)? My truck registers 20psi----seems low. SIR COL
  • 1i2cu1i2cu Member Posts: 32
    4 months old, 2700 miles. just broke the 10mpg. Celebrated with a shot of Gentleman Jack. Up to this point I have been getting 7-8 mpg, driving with an egg under the gas pedal.
    No matter how long you let the engine warmup, 1-5 minutes or how clod or warm the outside air is, the Allison will not shift out of low range until you drive 1/4 to 1/2 a mile. Then, after that it shifts at 2000 rpm and everyting is fine. Any comments ?
  • noobie1noobie1 Member Posts: 326
    Boy, Sir Col I'll be so pleased if I get the kind of mileage your getting. It makes me very hopeful. I've got the same truck except a long bed, and couldn't wait to check the consumption so after only 150 mi. I refilled the tank; 10.6 mpg, but in my case I couldn't keep my foot out of it. The salesman had told me, "The machining on these engines is so precise, you don't even have to brake these babies in. Just get in it and go." So after 175 mi. I read in the owner's manual, "During the first 500 mi, Don't drive over 55 mph, Don't punch it from a standing stop, Don't make any hard stops, Don't drive at one constant speed for a long time."
    DOH!!
    I just took my truck down the road to check the oil pressure: idling (700 rpm) with temperature at 195 deg., oil pressure is 28-30lbs. It stayed at around 40 lbs. until after being near that temperature for a few minutes. 20lbs seems low.

    1i2cu; Checked your interests during the drive. Mine shifts at around 1800 rpm (14 mph) no matter what the distance.

    -David
  • jrkracejrkrace Member Posts: 32
    When did you get your truck? Although the dealer quoted OCT 1 for a build date, the GM hotline still doesn't have one. They want me to call back in Three weeks!!!
  • sir_colsir_col Member Posts: 25
    noobie thanks for the check, and i wish mine would do 30psi hot and in gear. I wonder if there is a pressure valve of some sort that is adjustable, and that could be adjusted before any damage is done.
    1i2cu, mine shifts at 1800rpm,but hangs there untill 14-16 mph, hot or cold. My truck also stays in a lower gear untill speed increases to a shift point; so, for instance@ no load, at 30mph on city side streets it will hang in 3rd, and wont upshift to 4th untill 37mph, hot or cold.The shft pattern is unlike any other truck I have ever owned. SIR_COL
  • bobsquatchbobsquatch Member Posts: 136
    tAKE IT BACK. pROBABLY JUST A SENDING UNIT AND EVERYTHING WILL BE OK. If not the sooner you deal with it the less damage done.
  • 4x4man4x4man Member Posts: 222
    Well after I checked my oil pressure again after others were stating 20 psi seemed low (I freaked out!!). If you remember I posted to your same question in the 2500 topic. Well my bad, I was reading the gauge wrong (too much beer??), one notch is 5 psi, mine reads in between the two notches after 20 psi, so I am right around 27-30 psi (it seems to fluctuate a little) with engine around 200 degrees here in traffic today...anyway just thought I would add....

    Bob
  • noobie1noobie1 Member Posts: 326
    jr, I'm not sure what you mean by GM hot line. Do you mean Customer Service? Here's the way it came down with me: I'd been calling Cusromer Service (1-800-222-1020) since about three weeks after I ordered the truck on May 25. Finally got a TPW for 8-20. When I called on 8-24, they told me the truck had been built, but was still in smog check. I called again on 8-28 and they told me it was ready to ship, but no carrier had been chosen. When that occurred the VIN would be released and I could track it's movement. So I stop by the dealer Friday the 31st to work out the finale numbers. After getting home, he calls me and says, "If you go to the BNSF site and they tell you your truck is in New Mexico don't believe them. It just rolled off the transporter here at the dealership"(Hemet,Ca). WHA!
    So I picked it up on Sept. 4th.
    JR buddy, it's worth the wait. This baby's awesome! Hang in there man.

    Forgot to mention the delay in answering. I only have access to my computer on weekends. Sorry.

    -David
  • noobie1noobie1 Member Posts: 326
    You know, your mentioning an oil pressure adjustment reminds me, I really think I'm gonna buy a set of factory shop manuals. I'd feel a lot more comfortable just looking it up than relying on someone else's opinion. I think a full set is only about $150. At least if I have to go to the dealer I'm armed with the right information. Besides, I might just enjoy doing the simple stuff myself.

    -David
  • obyoneobyone Member Posts: 7,841
    but who knows with the demand for them....Only thing about the manuals is that they don't provide the GM part numbers that go along with the parts.
  • sir_colsir_col Member Posts: 25
    Where can they be obtained for a reasonable price, as that is an excellent suggestion. And who knows if it only save one trip to the dealership the frustration factor alone is worth the price of the books. Is a group sale possible, and we all culd get a good price? Thanks SIR_COL
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