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Hyundai Sonata Rear Thump

24

Comments

  • cableguy06cableguy06 Member Posts: 299
    Ed, my car was produced on 07/21/2006 and I have not experienced any of the noises stated on this chain. I now have 6500 miles and it's as quiet as can be. Sounds like I should consider myself lucky or keep my fingers crossed:)
  • silverfox1silverfox1 Member Posts: 91
    Road surface conditions are a factor. My 06 Sonata LX is Lexus quite on a smooth freeway. Secondary roads here in WI are choppy due to the winters and the car transmits what I consider abnormal rear suspension noise under these conditions.
  • ed_ged_g Member Posts: 16
    If not everyone is having a problem then why one some?

    I have a 2001 Volvo s40 with 113,000 miles that is quieter on bumps then my Sonata.

    If your Sonata is quiet then I wonder what it could be. A full car with luggage drove quiet on the highway and on bumpy road. Empty cvar drives quiet on the highway too. Maybe the shocks are too stiff. I would buy a quality brand shock if I could get them just to try. Have not seen any listed for a 2007 yet.

    I hope something comes up and the person who has a so called fix has some news I can pass on to my dealer. I like the rest of the car.

    Ed G
  • silverfox1silverfox1 Member Posts: 91
    I have added additional carpet padding between trunk carpet and floor pan. Slight improvement, but certainly not the answer. I have looked into aluminum covered rubber sheets that the audio people use but too expensive. I feel the problem may be the need of better use of bushings on the strut/shock mounts to the body. Have not looked under the car to see if the exhaust system has the proper clearance. Anyone out there with some ideas?
  • bobadbobad Member Posts: 1,587
    If not everyone is having a problem then why one some?

    As someone said, it's all in the streets. If the streets in your area are in good condition, you may go weeks or months without hearing it. Very rough or pot holed streets, and a driving between (approximately) 15-25mph really bring out the K-thunk noise. There are 2 rough streets and 3 or 4 RR tracks in my town that really make it sound off. Otherwise, the car is very quiet.
  • babbittdbabbittd Member Posts: 25
    I'm looking into the 2007 Limited and was wondering if this is this model also has the problem.
  • ed_ged_g Member Posts: 16
    They are the same except for accessaries. Make sure you
    hit some bumps in the road. If you notice a sound like the
    tires are bouncy or what people call a thumping noise that's it.

    If so, tell the dealer you do not like the care for that reason. Something wrong with the car.

    Let us all know what you find.
  • comet64comet64 Member Posts: 12
    Mine does. I have a 2007 Limited with 6500 miles. I mentioned it to the service manager and he indicated that he was aware of it and that Hyundai was "working" on it. ????????? Had I driven over some bumpy roads at 20-30 mph, I would have heard it and would not have closed the deal until it was addressed.
  • formersuver1formersuver1 Member Posts: 19
    I didn't realize there was a separate thread just for this problem--I just posted a response to this issue under "Owner Satisfaction...", message #11.
  • babbittdbabbittd Member Posts: 25
    Thanks for the reply. This is a disturbing problem and I wish you luck. I'm going to stay away from this car because this is the type of thing that will annoy me to no end.
  • silverfox1silverfox1 Member Posts: 91
    Thanks for the info. Contacted my dealer today and they have parts on order. Parts department indicates a back order situation on the parts. Dealer will call me when they are in. Glad to see this resolved. Car runs great otherwise.
  • ed_ged_g Member Posts: 16
    Parts,

    Is there a kit or are they just changing parts? What about as TSB?

    ed g
  • gbxk86agbxk86a Member Posts: 12
    Can you let us know the difference between before and after?
  • silverfox1silverfox1 Member Posts: 91
    Checked for TSB's on Hyundai web site and could not find anything on this problem. Dealer stated parts are ordered but did supply info or details. Will post more when the dealer notifies me that the parts are in.
  • bobadbobad Member Posts: 1,587
    This is certainly no reason to not consider the Sonata. The problem only occurs on 06 and early 07 Sonata's. You can only hear it when traveling very rough streets. Some owners never even notice it.
  • comet64comet64 Member Posts: 12
    A number of the K-thump discussions have referenced that the K-thump problem may be related to the build date of the vehicle. I have an 07 Sonata Limited with the infamous rear suspension K-thump. I don't believe that the K-thump is related to the build date,(at least on the 07's), but for my own satisfaction, how do I find the build date on this vehicle?
  • dump_truckdump_truck Member Posts: 42
    open your driver's side door, kneel down, and look to your right at the b-pillar.
  • bobadbobad Member Posts: 1,587
    Word is, the dealers have kits to fix the rear strut noise, and some owners are now getting the fix. I knew they would all along! :D
  • silverfox1silverfox1 Member Posts: 91
    Just had my rear shocks replaced with new left/right mounting brackets. K-thump sound gone. Anyone with this problem should contact your dealer for the kit. Warranty covers update.
  • drdonrsdrdonrs Member Posts: 164
    Just came back from the dealer. The service manager said the original order from Hyundai is for the 2007 Sonata with 6 cyl. engine( looking up the bulletin on the computer) However he had no problem ordering the parts for my car,2006 LX, taking the VIN # and should be in within a day or two. So the long quest has or is being solved. I discussed my front suspension noise on my Azera and he is investigating. See we get much further with a little patience and a "honey like" approach. We had a great discussion and he indicated that his interest is to see that the customer receives good service and is satisfied. :)
  • comet64comet64 Member Posts: 12
    My dealer indicated that he has about 15 of the kits coming and he will install mine on Monday (11/20). I'll post back after the fix is installed and report on the difference I notice.
  • aauummmaauummm Member Posts: 14
    Thanks to all of you guys for posting here. I was putting up with the "thump" from the rear of my 2007 Sonata Limited until I started reading your posts. The thump on mine only occurs on roads that have sharp humps on them such as a tar strip on a pavement joint. Mine was manufactured before 9/2006. I will contact my dealer about getting the fix. I have no doubt that my dealer will bend over backwards to make it right. Also, I notice a "twang" from the rear when going over the same type of bumps. It sounds to me like a torsion bar under stress that is tapped with a hammer. Maybe the "kit" will fix both problems. Thanks again for all the good info!!
  • ray_h1ray_h1 Member Posts: 1,134
    )) "It sounds to me like a torsion bar under stress that is tapped with a hammer." ((

    You might be closer to the truth than you realize. Antisway bars are lateral torsion bars which work by resisting relative side-to-side wheel motion differences when the car encounters cornering forces. It's possible one or both rear antisway bar's ends were not properly tightened to their links at the factory which resulted in that characteristic "ping" you alluded to if one or both ends shift position slightly on their link(s) - something to bring up with your dealer's service department the next time you're in. This is more likely an annoyance, not a safety issue.
  • ed_ged_g Member Posts: 16
    I just had the kit ( 55305-3K251-DQQH ) installed on my 2007 Sonata 3.3

    The thumping is gone. According to the service manager, the fit consisted of new
    shock inserts. There were no bushing changes.

    They have applied the kit to other cars in the lot as well.

    The suspension is not the quietest, but it is a heck of a lot better. No noiser then
    the $45,000 Lincoln Navigator I drove the other day. I am happy with the fix.

    I noticed a note on the service sheet ( Refer TSB # 06-01-011 ) What ever that means.

    I am sure you will notice a big change once it is installed.

    Ed
  • comet64comet64 Member Posts: 12
    My thump is GONE! Whatever fix Hyundai came up with, it completely eliminated the "thump". Apparently, they researched the problem thoroughly before offering a fix so that they fixed it right the first time. Good job Hyundai. However, I can't understand how they missed this to begin with.
  • ray_h1ray_h1 Member Posts: 1,134
    They thought Americans wouldn't notice.
  • cableguy06cableguy06 Member Posts: 299
    Now that's funny :D
  • pekelopdpekelopd Member Posts: 139
    I'm curious to know if anyone has complained if the 4 cylinder also has the rear thump and if anyone has had it fixed on the I4. I have the I4 '06 GLS for 7 months now and I hear faint suspension noises, and sometimes gas sloshing, but not that bad and I just dismiss it. Being that this is my first new car, I just assume it's natural. From what I recall, I don't believe anyone complained about the I4 having these problems and maybe it's just me looking for something wrong, or am I just being to forgiving?
  • ctc1ctc1 Member Posts: 66
    I have the I4 and while the thump doesn't sound as bad as everyone is saying it is still there. Brought to my dealer and they agreed. Parts are on order.
  • pekelopdpekelopd Member Posts: 139
    interesting.... after you get the parts, let me know if there's a significant difference. Maybe the next time I go to my dealer I should make some noise... Thanks for the info!
  • mamamia2mamamia2 Member Posts: 707
    Yes, please let us know what the dealer said and did, 'cause the typical THUMPING noise (which owners describe as K-Thunk) is a V6 issue, and Hyundai acknowledges it as a V6 issue, not an I4 issue (apparently the suspension is different bwteeen the 2 cars?), and the kit sent to dealer is a fix for the V6 cars.
  • ray_h1ray_h1 Member Posts: 1,134
    )) "Maybe the next time I go to my dealer I should make some noise..." ((

    Hey, better you than the car. As long as Hyundai's willing to take care of the matter on their nickel, why deny them the opportunity?
  • somanycarssomanycars Member Posts: 12
    I have a similar thump in my 07 V6 Sonata when driving over wavy pavement ( eg asphalt that has warped and very-patched up roads ). I bought my car at the end of September. I went back to the dealer and test drove another 07 and experienced the same noise. :( At that point I thought I was out of luck. Then I see the posting about the 'fix'. I called the service manager and he said that they were receiving the kit for their in-stock cars. He checked my VIN and said it was NOT in the list -- I find that very strange. :confuse: One of the service guys told me on the side that he also noticed that irritating noise when he borrowed one of the demo models. My car can't be any older than their in-stock cars. However, I have started a case with HMA and I am taking the car back next week for another checkout. I'll post the results.
  • jmonroejmonroe Member Posts: 8,989
    I just fell onto this board and it sure helped. I guess good things do happen when you are just nosing around.

    I too have noticed this K-THUNK problem on my 2006 Sonata LX purchased in June 2006, it now has 2378 miles on it. It’s the wife’s car which is used mostly to put me in debt by her shopping in the local area. This is the thanks I get for buying her a new car.

    I’ve noticed this problem almost from the beginning and I was getting ready to do some trouble shooting like some of you have already done. Now I don’t have to.

    I’ll probably just mosey on over to the dealer (armed with some of these posts) and discuss this issue and I’ll post back with my findings.

    BTW, I too didn’t notice this when I did the pre-purchase test drive which was only about 4/5 miles with two adults in the back seat. When I test drove the standard V6 non LX model that I was originally considering for about 15 miles (nobody in the back seat), I didn’t encounter this problem. I was beginning to think it was due to the LX having a tighter suspension but I still didn’t like the noise and was going to investigate like I already said.

    Thanks again to all and I’ll continue to be nosey since it seems to be beneficial.

    jmonroe

    '15 Genesis V8 with Ultimate Package and '18 Legacy Limited 6 cyl

  • patpat Member Posts: 10,421
    Hi jmonroe, welcome! Glad you found us. :)
  • jmonroejmonroe Member Posts: 8,989
    Hi jmonroe, welcome! Glad you found us.

    Thanks for the welcome Pat.

    Until now I've been hanging out over at the "Buying Tips: How DO I Get the Best Deal" and "Stories From the Sales Frontlines" forums here at Edmunds.

    However, by coming here, this may prove to have been very beneficial.

    There's no telling how many ways Edmunds can help car buyers and owners. Sooo, I'll just stick around till you guys start charging rent.

    Thanks again,

    jmonroe

    '15 Genesis V8 with Ultimate Package and '18 Legacy Limited 6 cyl

  • gbxk86agbxk86a Member Posts: 12
    "I heard the Sonata had the problem in the rear. I also remember talking to my service manager about them putting 4 cyl. Sonata struts on V6 equipped cars to quite them down"
    The above is from post 139 in the forum,Hyundai Azera Front End Problem. I remember when I mentioned to one of the service manager that my new Sonata is great, except the suspension noise is somewhat loud. He told me that he owns a 4 cyl sonata with 16" wheels. He had occasion driving a 6 cyl Sonata demo with 17" wheels and found it was noiser than his 4 cyl Sonata. He attributed to the difference in the size of wheels. After seeing the above quote in that forum, I wondered if it is because of the design of the shocks rather than the wheels. I dug out the specs on the shock absorbers between the two from Hyundai service website, with the following results:

    4 cyl weight 3266 lbs
    front expansion 1060N
    compression 680N
    rear expansion 440N
    compression 290N

    6cyl weight 3458 lbs
    front expansion 1640N
    compression 840N
    rear expansion 690N
    compression 240N

    These forces are all measured at a velocity of 0.3 m/s.
    I had two observations, the 6 cyl shocks produce generally quite high a damping force compared to 4 cyl's, relative to the weight difference. On the other hand, I am also puzzled that the compression of the rear at 0.3 m/s is actually lower than that of the 4 cyl. That does not seem to be logical, but there may be an engineering rationale. Of course, these numbers are just snapshots at a point on the whole damping curves.
  • bhmr59bhmr59 Member Posts: 1,601
    Thanks. But I'm too ignorant to understand what you are saying.

    Can you put this in plain English so we can all understand?
  • ray_h1ray_h1 Member Posts: 1,134
    )) "I'm too ignorant to understand what you are saying." ((

    Ah, c'mon - it's as simple as pronouncing gbxk86a's online handle... Seriously, I believe the numbers relate to the compression/rebound energy the dampers are required to control depending on engine choice (the V6 engine being the heavier of the two). Ironically Hyundai appears to have chosen a rear damper with a stiffer compression setting for the I4 model than that used for the V6 models*. File this surprising engineering rationale under, "Go Figure".

    *Perhaps Hyundai's product planners' way of "punishing" '07 GLS owners for being cheapskates? :D
  • bhmr59bhmr59 Member Posts: 1,601
    ray_h1, I think I get your drift. Thanks

    Now if YOU could only learn how to do "an internet search." LMAO!!
  • edmund2001edmund2001 Member Posts: 21
    I recently had the rear shocks replaced on my 2006 Sonata LX and it does help but I agree with a previous post that the front suspension also needs a correction to eliminate the dreaded ka-thump noises.
  • mamamia2mamamia2 Member Posts: 707
    ANY V6 Sonata, be it a 2006 or an early 2007 that has the K-Thunk prblem is eligible for a free fix done by your dealer -- or ANY dealership (since Hyundai PAYS them to do the work). The later 2007 production cars were equipped with the modified rear suspension on the assembly line.

    The 17" wheels being more noisy than the 16" is a FACT that has nothing to do with the K-Thunk suspension noise. It's the nature of the low profile tires. They are stiffer, noisier -- but have better grip of the road in high speed, especially when cornering. I personnaly hate them.
  • bobadbobad Member Posts: 1,587
    I'll be getting mine fixes as soon as I get a day off and an appointment.

    Agreed on the 17" wheels. They look nice, but looks are a much lower priority than comfort and noise. Besides, I like 6 spoke wheels better than 5 spoke anyway.
  • edmund2001edmund2001 Member Posts: 21
    Has anyone changed their wheels from 17" to 16" with higher profile tires? Does it help? Per a previous post, apparently there is a difference in the suspension specs between the V6 & 4cyl. models. I would hate to make the switch and still have the thump noises. I know it would be an expensive proposition but the ka-thumps annoy me to no end.
  • cableguy06cableguy06 Member Posts: 299
    Based on what I have read and know about this issue, I don't think changing your wheels will affect the "k-thump" issue. That issue is suspension based and not tire related.

    Changing the tires may provide a smoother ride but that is all I would expect.
  • ray_h1ray_h1 Member Posts: 1,134
    I suspect you're right, but the evil thought occurred to me that the stiffer sidewall of 50 series rubber might transmit tire patter noise more efficiently...
  • jmonroejmonroe Member Posts: 8,989
    ANY V6 Sonata, be it a 2006 or an early 2007 that has the K-Thunk prblem is eligible for a free fix done by your dealer -- or ANY dealership (since Hyundai PAYS them to do the work). The later 2007 production cars were equipped with the modified rear suspension on the assembly line.

    This is also a follow up to my initial post 88, on this subject.

    Very interesting situation, please bear with me on this.

    I finally decided to take my wife’s 06’ Sonata LX in for the K-thump problem. So, I emptied out the trunk and took it for a test drive. Guess what? I couldn’t hear the K-thump unless I tried to hit some real bumps. Let me point out that I live in the Pittsburgh area and although the weather here for the last few days has been in the 60’s (which is very warm for this time of the year) and while this is not cold it is colder than the 80’s when I have noticed the problem. I’m trying to reason, that since the oil in the struts is more viscous at 60F vs. 80F this may be preventing the struts from bottoming-out. Since I didn’t want to challenge my tires and rims anymore, I just decided to take it to the dealer anyway. I showed the dealer some of these posts, specifically post 73 by ‘ed_g’, about kit # 55305-3K251-DQQH and TSB# 06-01-011 and asked if this was valid information?

    One Service Advisor (don’t you love that title?) over heard my discussion with the Service Advisor I was talking with and said there is a recall for the 07’s but it didn’t apply to the 06’s. Meanwhile, my Service Advisor looks up the TSB and said it didn’t apply to the K-thump issue but it did apply to an engine/transmission computer adjustment. The kit # he didn’t see in his computer but he did say the suffix letters “DQQH” were not valid because Hyundai doesn’t use this numbering scheme. So, they said let’s take it for a test drive. I said fine but I don’t think you're going to find anything because I couldn’t. Off we go and of course, NO THUMPING. I couldn’t argue because I didn’t hear anything either. They said if the problem comes back, bring it in again and again I couldn’t ague with this. So I go home because there is no FIX for this problem. Let me also point out that the dealer I took it to, was not the dealer that I bought it from and I know it makes no difference what dealer you take warranty work to. However, I did buy my 05’ XG-350 from this guy so it’s not like I’m a total stranger to them.

    It gets even better. I just called the dealer where I bought the 06’ Sonata LX (other side of town about 20 miles away vs. 4) and asked if there was a ‘fix’ for such a problem and he said there sure is but for an 06’ it’s on an as needed basis. So, I tell him the story about the weather and he pretty much agrees with me. He says bring it in and we’ll go for a ride. Since I don’t feel it’s worth the trip, I’ll just wait till it acts up again.

    During our conversation he says he just got off the phone from ordering the kit for an 06’, further proof that there is a fix. I wanted him to confirm the kit # but it seemed he was very busy (I could hear people in the background calling his name a couple times) so he said don’t worry, the car has a 5 year warranty that applies to things like this and again said bring it in whenever I want it checked.

    It’s nice to know that I bought from one dealer that knows what’s going on.

    jmonroe

    '15 Genesis V8 with Ultimate Package and '18 Legacy Limited 6 cyl

  • drdonrsdrdonrs Member Posts: 164
    I had my 06 Azzy in for its 1st service yesterday and in discussing the Sonata rear suspension problem (I have an 06 LX)he told me that he has the kits in stock. Here is the deal. Hyundai acknowledges a problem, not a recall though. All 07's with 6 cyl. engines are scheduled for the fix and they (Hyundai)were going to wait for the older cars, 06's. I am making an appt. to get the "fix". He just came back from Hyundai school and the situation is this. The Sonata 6 cyl. cars have 17" wheels and they don't lend themselves to a quiet suspension, but the engineers felt the car "looked better" with 17" wheels. The 4 cyl. Sonatas come with 16" wheels and do not have the problem. He said the car if it had been equipped with 15" wheels would have had superior handling performance. It is apparent that if you really want the change it will be done on the 06's. It seems that the 17" low profile high performance tires are not such a "good" deal but look "pretty". I have made it a point to cultivate a good relationship with the service people and it will pay off in the long run. :)
    Don
  • rhduke00rhduke00 Member Posts: 129
    The Sonata 6 cyl. cars have 17" wheels...

    That's true for 2007 but not 2006. Sixteen inch alloy wheels were standard equipment on GLS V6 (same as 2007 SE except for the wheels).
  • cableguy06cableguy06 Member Posts: 299
    I stopped in to pick up a part at my dealer this morning and spoke to the service advisor. I shared with him what I was reading on the forum related to the TSB's for the "K-Thump" in the rear on the Sonatas and the noise upon engine start-up with the timing chain on the V6. For reference, I have a 2007 Limited Ultimate made on July 21, 2006 and purchased on August 18.

    He was keenly aware of both and stated that all I have to do is say that I'm having the problem and, without question or hesitation, they will take care of both. His final words were that when you schedule your next oil change, we'll pop the new rear shocks on for you...takes less than 30 minutes. The chain tensioner will require me to leave the vehicle there for a day. Not noisy enough to warrant having it done now but maybe later.

    WOW!!! The service I have received from my dealer has been incredible.

    I do believe, at the end of the day, that the dealership can make it or break it and maybe I just got lucky but customer service and satisfaction is certainly their #1 priority.
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