Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

Chevrolet TrailBlazer Maintenance and Repair

Karen_SKaren_S Posts: 5,095
Talk about Trailblazer problems and share solutions here.

Edmunds Manager UGC Click on my screen name to send a personal message. Need help navigating? Check out Getting Started in Edmunds Forums.
Need help picking out a make/model, finding inventory, or advice on pricing? Talk to an Edmunds Car Shopping Advisor



  • I have a 2002 EXT trailblazer that has a chronic road vibration that starts at 40 MPH peaks at 60 MPH and exists through 75 MPH. My dealer has looked at my TB 6 times and has no clue. The dealer does recognize that a heavy vibration exists but won't change out parts just because. On my own I replaced the drive shaft, rotors, and tires. Still no change. The vehicle shutters starting at 40 on up. My smooth ride of new is no longer. The problem was a slow gradual problem that is worse each month. I read all the other post and still I get no satisfaction or solid idea. My trailblazer shutters when the tranny is placed in neutral at 65 MPH. I even shut off the motor at 65 and still feel it so Im sure it not motor or tranny related. Towing makes it worse.

    ANY IDEA'S !

  • burdawgburdawg Posts: 1,524
    What kind of wheels do you have? Factory alloys or aftermarket?
  • It sounds like you have a bad tire(s). The tires of today break belts and unless the mechanic puts the vehicle on a lift, cannot tell they are defective. Sometimes even then it takes pulling the tires off. Have all your tires looked at. My 2000 Prizm had the exact same issue. Vibration would start at around 50 and stop once I hit 70. It was my tires. Your tires might be covered under defective warranties.
  • Wacky,
    I have own a ' 03 TBlzer LTZ and it experienced a very similar problem. A vibration in the rear drive train around 55-65 mph, especially in cruise. It was particularly a noticeable when carrying a cargo load or when carrying 4 adults. When in cruise and accelerating up a long hill, it was really a problem. I called the local (large) Chevy dealer who claimed that they never heard of such a thing and were not helpful at all.. I called a small dealership out in the county and the SVC mgr said right off that he knew what the problem was and furthermore, there was a GM service bulliten on it. The fix was a new set of rear coil springs. I called the big deal back and they still claimed that never heard of the bulliten. Anyway it took care of the problem for me.
    Good luck,
  • alcanalcan Posts: 2,550
    Sounds like classic driveline vibration caused by excessive or mismatched u-joint angles. Ask the dealer, or better still a shop which specializes in driveline service or off-road modifications, to verify front and rear joint angles. Should be 1-3 degrees with no more than 1/2 degree difference, if my memory serves me. Changing rear springs changes rear ride height and therefore changes u-joint angles. This is assuming that the driveshaft has been inspected to verify no dents or runout, and has been removed to properly check the u-joints.
  • Everyone thanks.

    The bad tire idea is just that, a bad idea. Tires have been replaced with a high end Goodyear Fortura tire. Same exact problem no better. I replaced the drive shaft with a one made of steel, this increased the problem 10 fold. The original was out of round by .030 front to back. Not a HUGE deal. I placed the aluminum back into the vehicle because the vibration made it un-drivable. The spring theory could be it. I'm just theorizing how that could fix it. The ride high makes or has no effect on the vibration at all. The U-joint angle could be set wrong from vehicle assemble I suppose but all of this was a gradual problem that got worse.

    One thing I notice those is the front end is very loose. The struts rattle over every bump. Sounds like their falling off at times. Maybe a connection their. My dealer is playing dumb and does not want to dig any further. Nothing like spending huge money and not getting the ride that it had when new. Their is nothing like making a payment on a vehicle that is a lemon. I must say those that of all the SUV's I have owned, this TB is the most comfortable of all.

    Keep the idea's coming in. I appreciate it.

  • "The bad tire idea is just that, a bad idea."

    I should have read your post more closely, I apologize for suggesting something you have already done. The other posts seem to be hitting on the possible problem. My EXT runs fine, so I'd appreciate an update if you find the solution in case I have to deal with it in the future.
  • Hi. My 2002 TB LT started something really strange a few days ago. As the days pass, the "symptoms" are becoming more apparent in different areas. Under normal conditions the following things should happen:
    ***Keyless entry should lock/unlock one/all doors with horn/lights.
    ***Rear window wiper and fluid should work
    ***When key is removed from ignition, radio should still play for ten minutes, interior light should come on and windows should still roll up/down.

    NONE of these are working or ALL of them are working. It's intermittent and hard to figure out the problem. If the door unlocks with the keyless remote, all of the above mentioned will work correctly. However, when i turn the engine off and the radio turns off too, I can't use the keyless to lock the doors and arm the alarm. I called the dealer (out of warranty of course) they said $500 for a computer Switch assembly with labor. Does this sound like a correct diagnosis? Any ideas? What can I check for? is there a site that has a diagram or description of what the modules do or which computer controls what? I'm lost. please help. :(
  • I have just replaced the transmission for the 3rd time in as many years. Has anyone heard of this before? My husband is urging me to trade it, but I don't really want to. Can anyone give me some hope?
  • The A/C fan on my 2002 TB has begun to work only when it feels like it. The air coming from the vents is cold, with or without the fan (I turn off the recirculate switch and the outside air will "adequately" cool the cabin when the vehicle is in motion). If I hit the top of the dash board a few times, after driving a while, the fan will often start blowing (although it seems like it is blowing lower than the speed it may be set on).

    Any ideas? I'm tempted to take the dash apart and look-see but I'm afraid I won't find anything I can simply fix. Someone suggested to me that the relay switch (located under the glove box) may be bad... it almost sounds like a poor connection or short too...but what do I know. in Las Vegas...A/C is a big issue... suggestions are appreciated.
  • Welcome to the TB air conditioning woes club. We have an 02 EXT and about 6 months ago had problems identical to yours. Thankfully we have the GM extended warranty. Ultimately you are probably going to have to have a new version of the thermostatically controlled cooling fan installed on your TB to fix the problem. Our dealer hemmed and hawwed, acknowledged that GM was having this problem with a lot of TBs and no real solutions. :cry: Finally after we located some info on the problem in the Edmunds "Trailblazer, Envoy, Bravada" postings and showed them to the dealer they "found" a TSB on the problem. A new fan and some re-pprogramming seems to have resolved our A/C woes. Suggest you check out the above mentioned postings, do a search for Air Conditioning and take the info to your dealer to get your A/C back to normal. Good luck.
  • I am having this same problem with both the vibration and the loose front end. I have taken it to the dealer about the squeaking over every bump, but they didn't hear it of course. Now I am having another problem (more serious) with the engine shutting off. I am taking it to the dealer today and will let you know what they say about the vibration. If you find the problem please e-mail or post it.
  • i have the same problem with the a/c. i have 02 tb, few months after we bought it rear a/c does not work so took it to the dealer and got it fix a few months later the same thing happen then the tail lights was not working properly and i think they have to fix it 3 or 4 times then one of my tail light has water inside the taillight itself because it's been raining it goes on and on then this past month the computer is not working during the trip to busch garden and took it to the dealer andit was the computer head board that cost $580 and has to stay for 3 days in the shop because they have to special order it and of course this happen on the 37,000 miles and you know what that mean it not cover anymore and now i am having problem with the power window on the rear side so i told my husband we are going to get rid of it before we spend more money on it and will never buy another chevy no more
  • I have a 2002 TB with 37k miles and recently started having problems with the oil pressure. My gauge reads that I lose oil pressure after about 20 minutes of driving and only when I'm decelerating. Otherwise, for the first 20 minutes and when I'm not slowing down the gauge reads normal. It has plenty of oil.

    Has anybody had problems like this? Also, I've read a couple of places that Chevy extended parts of the warranty for TB's for 5/60k. Is this true? This seems like a pretty big problem for a TB with low mileage.

    Any help would be appreciated. Thanks.
  • gmfangmfan Posts: 188
    You would need to tell us what your oil pressure gauge in reading. I have an 02 TB with 75K miles and at idle when engine is warm, my oil pressure is very close to if not at 40. Each time I accelerate or race the engine, it will increase. If I run it hard, it is common to watch the pressure to rise to around 60. This has been the characteristic of mine since brand new. If yours is displaying a lower oil pressure (specifically at idle while engine is warm), then there could be a manifold leak that a new gasket will fix...not too expensive around $300 for parts and labor. Let us know what your pressure is displaying.

  • gmfan, really curious now as to what manifold leak affects oil pressure.
  • gmfangmfan Posts: 188
    I meant valve cover leak with worn seals/gaskets. Or, it could be an oil pump that is going bad, are you using 5W-30 or 10W-30 motor oil? If you are using the thinner oil, why not change the oil with the thicker one to see what happens before you take it in. What is your oil pressure reading at idle? If it is reading at or below 15, I would immediately change the oil. If that does not take care of it, then you would need to take it to mechanic since he has an oil gauge tool. How many miles are on your vehicle?
  • When i first start my car, my oil pressure is normal (right around 40) but after driving for around 20 minutes, when i decelerate or let it idle it will then drop to nearly 0. As soon as I hit the gas it jumps back to 40. I believe I'm using 10W-30 oil right now.'

    My car only has 37k miles on it. I took it to the dealership today, but would appreciate anymore feedback so I can ask the right questions after they diagnose.

    If it is a bad oil pump, would GM possibly help defray some of the costs (since it has such low miles and just left the 3/36k warranty period). If so, do i discuss with the dealer (not where i bought the car) or call GM?

  • My 98 blazer is loosing coolant approx. 1 gallon + a week. It doesn't smoke, it has no leaks any ideas what it might be. My guess is the head gasket? :confuse:
  • Mr_ShiftrightMr_Shiftright Sonoma, CaliforniaPosts: 58,496
    It has to either smoke or leak, no other way to lose that much that fast. Try a pressure test to "force" the leak.

    MODERATOR --Need help with anything? Click on my name!

    Share Your Vehicle Reviews Here

  • gmfangmfan Posts: 188
    If it is a bad oil pump, then I would ask the dealer to call Chevy to discuss the problem (low mileage, oil maintenance records, etc), especially if the repair cost exceeds $400. In the event the dealer does not help, then I have had success calling Chevy Customer Service to discuss problems out of warranty. I had the well-known battery acid leak problem when I was at 50,000 miles, out of factory warranty (and extended warranty would not pay $). It was a pleasure talking with Customer Service, they called my dealership to verify the info and that the car was actually at the dealership, then they paid the acid cleanup and installed a new better battery. Of course, I made it clear this was my first Chevy purchase. I am glad you have it at the dealership with that oil pressure reading so low. How many miles do you think have past since your last oil change? Let us know how it goes.
  • Thanks for all the info. I will definitely take your advice re: calling Chevy if it is an oil pump problem. The car has been well maintained and is rarely driven. It's been just a little over 3 months since my last oil chance and I've put 800 miles on my car since then. The TB is also my first Chevy and it seems I've been a lucky TB owner as this is the first problem I've had with the car.

    I will definitely keep you posted how this plays out.
  • burdawgburdawg Posts: 1,524
    My sister in law had a similiar problem on her Tahoe. Turned out to be the sending unit. Hopefully your problem is something as simple also.
  • The GM service manual for the TrailBlazer indicates that the replacement of the outlet heater hose requires removal of the transmission. Since hoses are not a warranty item, replacement of a relatively cheap part that is subject to wear becomes labor intense (costly) if the transmission needs to be pulled. I notice the outlet heater does snake around the top of the bell housing, which I suspect is why the manual calls for the removal of the transmission. Can anyone tell me from their experience if the transmission really needs to be pulled to install a new heater hose?
  • A gallon a week is a lot of coolant to disappear without leaving evidence behind. Cover the basics first in trying to sort out if you have a big vs. little problem. If you have a bad head gasket some or all of the following could be happening: Check your oil dipstick and if the oil looks foamy / grey and frothy then you've got coolant making it's way into he lubrication system. If the oil looks OK on the dipstick then allow your engine to cool or better yet, start with a cold engine, remove the radiator cap and start the engine. If you have a blown head gasket that is allowing products of combustion to enter the cooling system you will see bubbles in the radiator filler neck. May have to let the engine warm up some for this to work because if you have a bad head gasket, head or block surface problem it's probably not going to make itself apparent until your engine reaches normal operating temp which causes the different mating surfaces to make dimensional changes relative to heat.

    A head gasket problem that loses a gallon of coolant a week is probably also going to manifest itself in visible loss of power, overheating. I want to give you a little hope here by saying if you are not noticing anything else other than loss of coolant then you probably have something else going on besides a head gasket but just have not found it yet.

    How many miles on your blazer? Have you pressure tested the radiator cap? If yours is a 98 and you've never replaced the cap now would be a good time. How about your water pump? Most of the time when they leak they do so through a weep hole on the underside of the pump casting where the impeller shaft runs through and leave a puddle but not always. With the engine off and key out of the ignition grasp a fan blade and they to wiggle it up and down or side to side. If you've got some play then it's time to have a mechanic check the waterpump. While you are at it, how are your radiator / heater hoses. When did you replace them last. The factory wire hoseclamps are junk. Replace them when you have a chance with real hose clamps, not the formed wire factory junk. If you have a leak on a hose at a joint that is near the exhaust manifolds, well the coolant will turn to steam once it comes in contact with the mainfold and all your evidence more or less goes up in smoke to be cliche.

    I've saved the easiest for last and it's something that is frequently overlooked: Your heater core might be leaking. Check the carpeting on the pasenger foot area where the carpeting works it's way up the firewall. If you've got a leak there the carpet will be wet.

    These are just some thoughts and ideas but if some of the things I've written above sound totally foreign to you you might be ahead of the game getting your blazer in a shop for a coolant system pressure test. Just giving you some ideas to try to save a little money by eliminating the obvious. Good luck. I bet you are going to find it's something minor. :)
  • rwannrwann Posts: 1
    i took my 2002 trailblazer into the gm dealer for the recall work ,oil change, and a cam sensor problem. they replaced the cam sensor and did all the work including a tune up. i noticed an oil smell a week later and when i checked the oil i noticed the oil had been overfilled. i didn't do anything about it because they told me i had some oil blow by and i figured they overfilled on purpose. about two days later i noticed lots of oil spots on my driveway. when i took it back they said the air filter was saturated with oil due to the blow by and that i had no loose oil filter etc. they said it would require an engine replacement. it never leaked b4 i took it in. ithink i am being scammed. would the overfill cause this problem? how do i fix the leaks. they say it is oil blowing on the engine and dripping off. possible?
  • I have an 04 Chevy Trailblazer 5.4 V8 Engine. When I am at an idle, or low speeds, you can feel the car vibrating. This happens intermittently, so sometimes it happens and other times it won't. I have taken it to the two different dealers for a total of three occasions, and each time, the service technicians have told me that the vibration is a "natural characteristic" of the car and that there is no fix. I have told them that on a new car, this is unacceptable. I then went into talks with GM and they too have said that this is natural and that they can not fix it and will not replace the car.

    Has anybody else seen this or have had problems with this vibration. Any help is greatly appreciated! Thanks!!
  • I have a 2004 Trailblazer that continues to have electrical problems. Problems range from the engine momentarily cutting out, to the security light or the check engine light flashing, to the headlights dimming when the vechile shifts. The dealership acts like I am a psycho to bring up these problems and deny they can find anything wrong. They have reprogramed the Trailblazer so many times, it should be able to do it on its own now. My husband talked with one of the service techs who said his sister's Trailblazer had similar problems. I get the sense they do not know how to fix it ... but then they are very dismissive of me any time I am there. Make my husband deal with them now. Have also had problems with a vibration at about 60 mph and an a/c leak. Did I just get the lemon, or is this common???? :confuse: :lemon:
  • 2002 Trailblazer...only 30,000 miles :surprise:
    Here's a good one!!!!
    Service engine soon light came on intermittently, then stayed on & reduced engine power light would come on too when car first started in the morning. aAfter car was running a while I restart car & reduced engine power light turns off but Service engine soon light still on. Brought to chevy dealer who put it on the computer & the following codes came up:P0530, P1221, P1634, P1481, P1635. They say main harness is rubbed through & faulty throttle body & both need to be replaced. I take car to my mechanic who does not see any damage to main harness, so thinks it just might be throttle body & orders the part. In the meantime I'm driving my car again & if upon exiting my car I turn on securuty system, all sensors get cleared out & car is running fine. What's up with that? Body control module shouldn't affect fuel system sensors?????
Sign In or Register to comment.